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Easy Parenting: Brood Parasites Get Someone Else to Do the Hard Work

Friday, September 25th, 2020 | Petrina Duncan | No Comments

 For most birds, reproduction is a life process that takes up a lot of time and energy. There are huge energetic costs to a female bird with respect to mating, egg-laying, incubating the eggs and feeding hungry chicks for many weeks or months. Some birds also migrate vast distances across land and sea before breeding can commence, using up even more time and energy. Breeding for a bird is a lot of hard work.

So, if a bird found an easier way to become a successful breeder, we would expect that behaviour to be favoured by natural selection and become fixed. In about 1% of all bird species, that’s exactly what has happened: it’s called brood parasitism.

Brood parasites are birds who have learned how to make the parenting process much easier. They still have to find a partner and mate successfully, but instead of the female bird laying her eggs in a nest that she and/or her partner made, she stealthily lays them in the nest of another bird. Intraspecific brood parasites lay eggs in nests belonging to birds of their own species, compared to interspecific brood parasites who target other bird species.

Common cuckoo chick in the nest of a tree pipit.

Common cuckoo chick in the nest of a tree pipit.

 

 

 

 

 

 

 

Benefits and advantages for the brood parasites:

  • Increased breeding output
  • Minimal energy expenditure because they don’t defend a nest, incubate eggs or feed chicks.
  • Genes passed on to the next generation.

Costs and disadvantages for the host birds:

  • Decreased breeding output
  • Expending more energy raising someone else’s offspring, especially if the parasitic chick is very large as more food will have to be found.
  • Not passing on genes to the next generation.

Generalists and Specialists

Some brood parasites put their eggs into the nests of a wide variety of other species. These are called generalists. An advantage of this behaviour is the flexibility it offers. Generalists can be successful in many different places and at almost any time, as long as a suitable host bird is nesting nearby.

Alternatively, brood parasites can be specialists. They will target one species to be the host of their egg/s. The limiting factor in this approach is the lack of flexibility, as parasites must live close to their host species or spend time and energy travelling to find them during the breeding season.

 Brood parasites in New Zealand

Cuckoos are the most famous brood parasitic birds worldwide. In New Zealand, two migratory species of cuckoos arrive on our shores in September and October each year. The shining cuckoo/pīpīwharauroa (Maori name) is the smaller of the two species. These small birds fly all the way from the Solomon Islands and the Bismarck Archipelago, a distance of more than 5000 kilometres. On arrival in NZ, shining cuckoos/pīpīwharauroa seek out their target host species, the tiny grey warbler/riroriro, in forests and gardens across the whole country.

Shining cuckoo/pīpīwharauroa being fed by its host parent, a grey warbler/riroriro.

Shining cuckoo/pīpīwharauroa being fed by its host parent, a grey warbler/riroriro.

 

 

 

 

 

 

 

 

 

Long-tailed cuckoos/koekoeā fly to NZ from even further away. They spend winter in an arc of Pacific Islands which extends from Henderson Island (Pitcairn group) in the east to Palau in the far west of Micronesia. A long-tailed cuckoo/koekoeā migrating from Palau to NZ will fly more than 6700 kilometres – perhaps that’s why they don’t have the energy to be a ‘normal’ bird parent. They arrive in NZ in September and October to begin searching for their target host species. In the North Island, they look for a small bird called the whitehead/pōpokatea in tall, mature forests. The forests of the South Island have two host species for long-tailed cuckoos/koekoeā: the brown creeper/pīpipi and the rarer yellowhead/mohua. All three of these host species are endemic to NZ and closely related.

Whitehead host parent feeding a young long-tailed cuckoo

Whitehead host parent feeding a young long-tailed cuckoo

 

 

 

 

 

 

 

 

 

 

 

Strategies of a successful brood parasite

  • Be selective. Brood parasites take their time to find the best host ‘mum’ to be a surrogate parent for their offspring. In human terms, this is a like parents shopping around to find the very best day care centre for their toddler. Before putting her eggs into a host’s nest, the parasitic bird will watch a potential ‘mum’ closely to appraise her age, condition, singing ability, territory location, size of the nest and its location. These factors will contribute to the parasite’s final choice of the best host for the job.
  • Team Work. Some parasitic bird pairs work together to achieve their goal. For example, male great spotted cuckoos in Southern Europe will stage an attack on an unsuspecting pair of magpies. The male cuckoo appears in full view of the magpies to divert their attention and launch a pretend attack. Meanwhile the female cuckoo sneaks into the magpies’ nest to quickly lay her egg. This risky egg-laying behaviour is only possible because both the male and female are working as a team to ensure the hosts don’t see what’s happening.
  • Egg mimicry and timing of laying. Parasitic bird eggs have evolved over time to look and feel very similar to the host’s eggs, a concept called egg mimicry. This reduces the chance of egg rejection by the host. Their eggs also usually have thicker shells than the host’s eggs. Parasitic birds will also strategically time their egg laying. By waiting until the host has already laid a few eggs, the parasitic female ensures that incubation is already underway.
The larger blue egg is that of the parasitic common cuckoo. The cuckoo’s egg looks very similar to those of the host, a common redstart

The larger blue egg is that of the parasitic common cuckoo. The cuckoo’s egg looks very similar to those of the host, a common redstart

 

 

 

 

 

 

 

 

 

  • Chicks who are bullies. Brood parasite eggs generally hatch earlier than the host’s eggs. The parasitic chicks use strategies like pushing the host’s eggs and chicks out of the nest or stabbing chicks with a special hook on their beak. Imposter chicks also tend to make louder, more frequent begging sounds to ensure they get all the food from host parents. Some species like NZ’s shining cuckoo have chicks who can mimic the begging call of a grey warbler’s chicks, ensuring the host is fooled into feeding them.
  • Total destruction of eggs. Sometimes a cuckoo misses the chance to lay her eggs at the optimum time. As an extreme measure, she will destroy the entire egg collection in the host’s nest. This behaviour is like a reset for the host bird to start over with breeding. She will probably mate again and lay another clutch of eggs while the watchful parasite bird prepares to intercept at just the right time.
Common cuckoo chick in host nest

Common cuckoo chick in host nest

 

 

 

 

 

 

 

 

 

 

Can host birds fight back?

Brood parasitism is a classic coevolutionary “arms race”. Each time a host species evolves a new behaviour to defend against brood parasitism, the parasite species evolves a new trait which makes its breeding strategy more successful. Here are a few ways in which hosts can fight back.

  • Egg recognition. Many host birds have evolved to be experts at egg recognition. They will recognise and then reject eggs which look different to their own. Sometimes a host will even leave its nest entirely if a strange looking egg appears. However, brood parasites have adapted to this selection pressure by either becoming generalists (they parasitise multiple species) or producing eggs which are almost identical to the host’s eggs (egg mimicry).
  • Chick recognition. Some host ‘mums’ are able to recognise and reject chicks which are not their own. However, rejecting chicks carries the risk of mistakenly rejecting their own chicks. If the rate of parasitism is very high, selection for accurate chick recognition will be stronger.
  • Nest features. Species that commonly get parasitised may deploy nesting tactics to minimise interference. Their nest may be well camouflaged to avoid detection. The nest’s location could be away from places where parasitic birds can sit. The nest entrance may be too small for the brood parasite to enter. For example, the grey warbler’s nest entrance is tiny, preventing shining cuckoos from entering. But the cuckoo manages to parasitise their nests regardless. Researchers suspect the egg is laid elsewhere then carried in the cuckoo’s beak up to the warbler’s nest and carefully deposited inside.

Should we be concerned about brood parasitism?

As our climate changes and the human population continues to increase, natural habitats such as forests are disappearing due to fires, logging, agriculture and urban sprawl. For bird species that are already in decline due to habitat loss, brood parasitism  may pose a significant threat, especially if generalist parasites increase in numbers. Reproductive success will be compromised at a time when the population is already decreasing. The combined pressures could become too much, putting the species at risk of localised extinction.

On the bright side, a brood parasitic species can’t survive without its host species. Parasitic birds often wait until their target host has raised one clutch of offspring before parasitising the second nest. This is a behaviour which will give rare host species a helping hand.

Grey warblers will often raise a family of chicks successfully early in spring, before the shining cuckoos arrive in NZ from their long migratory journey. Even if the grey warbler’s second nest gets targeted by a shining cuckoo, they have already contributed their genes to the next generation and hopefully the behaviour of early nesting was also passed on to their offspring.

For rarer NZ bird species such as the yellowhead/mohua and whitehead/pōpokatea, being less successful breeders due to parasitism by long-tailed cuckoos/koekoeā is a concern to conservationists. Long-tailed cuckoos are also able to parasitise the nests of the more common brown creeper/pīpipi in the South Island. As yellowhead numbers decrease, brown creeper numbers may also begin to decline due to being parasitised at a higher rate. In the North Island, whiteheads are increasing in numbers due to human conservation efforts which will hopefully help to mitigate the negative effects of brood parasitism.

Conclusion

Brood parasitism represents a rare and unusual parenting strategy. There are many benefits for the bird who does the parasitising such as avoiding most of the hard work involved with being a parent.

Brood parasitism is a great example of coevolution in which the evolutionary “arms race” is played out in the privacy of a nest or within the boundaries of a territory. There will always be winners and losers in this host-parasite exploitative relationship. What we must try to do is reduce or eliminate human-related pressures which adversely affect the breeding success of birds. By helping to conserve native bird species and their habitats, we’ll be supporting them to withstand the negative impact of brood parasitism long term.

Further reading:

Photo Credits:

Common cuckoo chick in the nest of a tree pipit.
Vladlen666/WikiMedia Commons (CC1.0)
https://www.sciencenews.org/blog/wild-things/cuckoos-may-have-long-lasting-impact-other-birds

Shining cuckoo/pīpīwharauroa being fed by its host parent, a grey warbler/riroriro.
Photography by Robin Colquhoun. From NZ Birds Online: http://www.nzbirdsonline.org.nz/species/shining-cuckoo#bird-photos

Whitehead host parent feeding a young long-tailed cuckoo. Photography by Adam Clarke.
From NZ Birds Online: http://nzbirdsonline.org.nz/species/long-tailed-cuckoo

The larger blue egg is that of the parasitic common cuckoo. The cuckoo’s egg looks very similar to those of the host, a common redstart. Photography: Dr. Tomas Grim. https://phys.org/news/2018-05-russian-cuckoo-invasion-alaskan-birds.html

Common cuckoo chick in host nest. Photography by Per Harald Olsen (CC BY 2.0)
https://www.birdorable.com/blog/bird-term-brood-parasite/

The Unknown Explorers of Prehistory

Friday, July 31st, 2020 | STEPHEN BRONI | No Comments

As a boy I had a fascination for Arctic explorers; Nansen, Nordenskjold, Peary, Franklin Cook, and a Scot by the name of John Rae. Many years later when working as an interpretive tour guide at Denali National Park in Central Alaska I found myself working alongside Yupiks, Athabascan and Aleuts and was reminded that as my boyhood heroes pushed north in their clunky wooden-hulled ships in search of that elusive Northwest Passage they encountered people already living on that frigid landscape and who had been for thousands of years.

Where did they come from? When did they arrive and how did they get there?

The classic story I learned at school was that first Americans crossed the land-bridge (Beringia) from Siberia at a time of warmer interglacial climate around 11,000-14, 000 years ago.

However, this is assertion is increasingly being challenged by recent archaeological finds.
What is emerging is evidence of a much earlier arrival than previously thought at a time of `Glacial Maximum’ when the `land-bridge’ was buried under kilometre thick ice sheets.

Who were these men and women – these nameless explorers of prehistory – and could they really have crossed a Beringian ice-cap?

Anatomically they were the same as you or I but what did they wear, how did they navigate, how did they survive such hostile conditions?

What were their hopes, dreams, aspirations and fears as they pushed further and further into an increasingly hostile environment? Were they driven by the pursuit of something new and better or fleeing from something bad?

Or is it simply that the urge to make ‘split-infinite journeys’ and “boldly go where no-one has gone before” is inherent in us as a species. That pull of the far horizon, to explore, took us out of Africa and remains with us today as we plan to colonise other planets.

The more one delves into what we know of these earliest of Arctic explorer/colonisers one can’t help but admire the tenacity, resilience and bravery they must surely have had to cross from Asia to Alaska and down through the Americas.

Until recently the commonly held theory was that the first human inhabitants of the Americas arrived somewhere around 11,000 years ago. Known as the Clovis people after a characteristic type of stone tool first found at a site in Clovis, New Mexico in the 1930’s their stone tools have subsequently been found across the Americas.

Then, in the 1990’s evidence began emerging from a number of sites of earlier occupation, the most famous and controversial being the Monte Verde site way down in Southern Chile. Monte Verde sparked intense controversy within the archaeological community as it claimed evidence of occupation as early as 14,500-18,500 years ago. To have reached Southern Chile by then those first colonisers would have had to have crossed Beringia much earlier than previously thought. ‘’Not possible” say the glaciologists! Beringia would have been covered in kilometre deep ice sheets at that time.

Could they have snuck around the southern coast of Beringia? Perhaps these tenacious early colonisers coastal hopped up the east coast of Asia, round to the Alaskan Archipelago, down the British Columbian coast to California, Mexico and beyond to South America.
This Coastal-Settlement Theory is gaining more and more traction with archaeologists as new sites are discovered.
Sea levels at that time of Glacial Maximum would have been up to 120 metres lower exposing many coves, beaches and islands submerged today. The single longest sea journey might well have been less than 200km.

Marine Archaeology is challenging at the best of time but nowhere more so that around the Bering Sea and Alaskan coast, so gathering evidence for the coastal- settlement theory remains challenging. While only a few coastal sites have been found dating from about 11000-15000 years ago the search continues as new archaeological techniques and technology develops.

What we do know is that as early as 60, 000 years ago proto-Melanesians were a seafaring people. There is evidence of voyages of 150- 450 km by 32,000 years ago. All of which supports the idea of a possible coastal settlement path up the coast of Asia and across to the Alaskan Coast of the Americas.

The Chiquihuite Cave Site
Now a newly discovered site in Mexico has pushed the arrival of the first Americans back even further -a whole 15,000 years earlier than previously thought!
Chiquihuite Cave is located far inland in a remote mountainous region at a height of nearly 3000m. Over 2000 stone tools have been unearthed along with other evidence that push the arrival of the first Americans back to 25,000-30,000 years ago!
“We don’t know who they were, where they came from or where they went. They are a complete enigma. We falsely assume that the indigenous populations in the Americas today are direct descendants from the earliest Americans, but now we do not think that is the case.
By the time the famous Clovis population entered America, the very early Americans had disappeared thousands of years before. There could have been many failed colonisations that were lost in time and did not leave genetic traces in the population today”. Says Archaeologist Dr. Ciprian Ardelean.

No human remains or DNA has yet been found at this site so it is not possible to know for sure the genetic lineage to possible founder populations in Siberia and Beringia.
The traditional view that most Native Americans (in both North and South America) are mainly descended from the same ancient peoples that most Chinese, Japanese and other East Asians are descended from is now also being challenged by recent genomic research. This suggests that the initial peopling of the Americas was probably carried out by a different group of people partly related to ancestors of modern-day Australian aborigines, Papua New Guineans, Andaman Islanders and Mamanwa people from the Philippines.

Whether those early explorer colonisers fought their way on foot across expansive glaciers and down an ice-free corridor within Alaska or battled stormy seas around the fringes of a frigid Beringia they must have been remarkably tough and resilient individuals and communities.
The individual identities  of the very first to  make the crossing will remain forever unknown. Since we have no Nansen, Nordenskjold or Peary to be our Arctic explorer heroes from that era we are left with a collective reverence for an unknown people who had the tenacity, endurance, drive and fortitude to make the toughest migration since our species walked out of Africa somewhere around 80,000 years ago.

Sources & Further Reading:

YouTube Links:

Most archaeologists think the first Americans arrived by boat. Now, they’re beginning to prove it
https://www.youtube.com/watch?time_continue=6&v=CmxhFgpIacI&feature=emb_logo

How the First Americans Got There
https://www.youtube.com/watch?v=5dyjZBJt-Yg

Landmark find rewrites world’s prehistory as it is currently known
https://www.independent.co.uk/news/science/archaeology/archaeology-discovery-americas-us-human-story-prehistory-a9632161.html

Earliest humans stayed at the Americas ‘oldest hotel’ in Mexican cave
https://www.sciencedaily.com/releases/2020/07/200722112726.htm

Evidence of human occupation in Mexico around the Last Glacial Maximum
Ciprian F. Ardelean, Lorena Becerra-Valdivia, […]Eske Willerslev : Nature (2020)
https://www.nature.com/articles/s41586-020-2509-0

Illustration credits:
1. Tyler Jacobsen
2. Kenneth Garrett
3. Chris Burns
4. Dr. Ciprian Andelean

Are ALL Viruses Bad?

Thursday, March 26th, 2020 | STEPHEN BRONI | No Comments

graphic of sausage-shaped bacteria with pin-like viruses attachedWith all that is going on  around us,  all across this beautiful planet of ours and the word `virus’ dominating everything we see, hear, read in the media at the moment I found myself thinking “Are all viruses bad? Are there any useful, beneficial viruses? And  why  ARE bats  such good carriers  off so many nasty diseases – over 60 of them!”

It seems highly likely that viruses do play a substantial part in maintaining a healthy body.  You have probably heard of our `microbiome’ but what about our ‘virome’
Read more here:
How ‘good’ viruses may influence health 
Here:
Not All Viruses Are Bad For You. Here Are Some That Can Have a Protective Effect
And here:
Viruses Don’t Deserve Their Bad Rap: They’re The Unsung Heroes You Never See
[In  the embedded Ted-X talk in this link, the always engaging, Peter Pollard also  illustrates some illuminating facts about how much C02 freshwater ecosystems pump into the atmosphere, due in part to viruses… everything is linked! ]

And on the question of why bats are such good carriers of disease.Brown bat in flight
Check out:
Why Do Bats Transmit So Many Diseases?

BEFORE YOU CLICK-  Spend a minute thinking about what you know of bat behaviour and basic physiology …. (The answer may take flight in your head…(hint))

 

However, when all is said and done our thoughts are all on one virus at the moment.

Ever wondered how the tests for Coronavirus work?
May you never have to take one!

P.S.
Need a refresher on just exactly what viruses are and how they work?
Check out this great Khan Academy Tutorial on Viruses and the  text Q&A that follows.

Stay safe
Be patient

Science Academy 2019 Student Podcasts

Wednesday, October 2nd, 2019 | STEPHEN BRONI | No Comments

Exploring  effective techniques for communicating science to a public audience is a key component of Science Academy (OUASSA). Every year our students undertake a project under one of four science communication streams:- Interpretive Science Talks, Science Film Making with your cell phone or Ipad, Museum Science Communication, Science Radio Podcasting.

This year Shannon Colbert and Domi Angelo-Laloli from Community Access Radio’s OAR  105.4FM Dunedin mentored eight of our students  through the process of constructing a short science podcast by means of interactive workshops in the studio and on-line  support throughout the year.

Below is a list  of the topics they covered

Physicists on the Pitch
by Abdul Ahmadi from Mangere College

Discover the science behind Soccer! From Newton’s Laws of Physics, to the Magnus Effect and the use of `Cleats’.

Operation: Space-cial Exploration
by Jessica Marshall from Opihi College

Billions of stars, hundreds of planets, a black hole or two, but how do we know this? What feats of engineering were needed to bring us this knowledge and what will be needed to further understand the world around us?

The Periodic Podcast
by Niamh Frizzell from Awaptapu College

This podcast is about history of the periodic table, the `International Year of the Periodic Table’ and the celebrations that surround it.

Error 1387 Gene Unavoidable
by Seruwaia Matairavula from Wesley College

In this podcast I discuss Genetics at Otago University and how the study can benefit humanity. I am accompanied by Sean, a Masters student studying genetics, and Science Academy attendee, Cameron Bergin from John Paul II High School in Greymouth.

The Extra-terrestrial Podcast
by Corban Taylor from Opotiki College

If you want to listen in to a good friend and I talk about aliens and all that jazz then listen in, as we discuss our views on alien beliefs.

Are We Living in a Simulation?
by Maddison Ridder from Verdon College & Cameron Bergin from John Paul II High

Have you ever felt like you have no control, like your whole life is set out for you? Have you ever thought that maybe you’re living in a simulation? Well, it’s more possible than you’d think. This podcast is going to investigate the reasons why we could be part of a simulation.

Lost in Translation
by Gemma Marnane from Central Southland College

If you are willing to deny convention, it becomes more worthy of attention. For all the knowledge, all the fear, we forget to speak of the meaning, which is hidden. Take this, imagine a world in words. It forms languages and societies, stipulates mutations, natural selection and forms gene pools and populations. It’s the world. We are all just a little lost in translation.

Becoming a Midwife
by Tamel Robertson from Aurora College

My podcast is based on the life of a midwife and the duties in her role. I will be interviewing midwife Margaret Gardner to gather information for the listener as well as myself as I plan on beginning my study to become a midwife next year, in 2020.

Have a listen here at   https://oar.org.nz/event/science-academy-chat/

Happy Listening!

I’ve been thinking….

Friday, August 30th, 2019 | Wendy Dunn | No Comments

Actually it starts with listening, thinking, reading and then some more thinking. The nature of Science learning! This year I have had the luxury of having the opportunity to listen to the radio while I am working. I find my ears prick up and I tune in when an interesting science item comes on. Radio New Zealand is my frequency of choice. Even if it’s not yours it is well worth dipping into for anyone with an interest in keeping up with the latest Science news. They are easy listening and many of the programmes and interviews are available as podcasts (see below). The RNZ website is easy to search and there is a RNZ App if you like to listen while on the move.
Here are a few recent items that you might find interesting.

A very ugly lamb

A rare lamb was born in Rotorua that is basically bald – a lamb without wool. What would happen to this genetic rarity in the wild?bald lamb

 

 

 

 

https://www.rnz.co.nz/national/programmes/checkpoint/audio/2018710142/woolless-lamb-one-of-the-ugliest-lambs-i-ve-ever-seen

The Mosquito.  Our deadliest predator and a fascinating discussion about Sickle cell.

https://www.rnz.co.nz/national/programmes/ninetonoon/audio/2018709821/the-mosquito-our-deadliest-predator

Professor Timothy Winegard of Colorado Mesa University talks about the impact of the mosquito – the deadly diseases it carries have killed as many as 50 million people. One such disease is malaria. Individuals with the genetic condition sickle cell anaemia have resistance to malaria.
I found the section on American Football players who had sickle cell anaemia dying, or, coming close to dying, after pushing their body to the limit, particularly interesting. The deformed cells cannot carry enough oxygen and clog the blood supply to the muscles and tissue leading to tissue death and potentially a heart attack. Those of you who follow sport know that playing sport at high altitude, where there is less oxygen, is difficult and when players with sickle cell take to the field they are particularly vulnerable. This happens when the American Football players with sickle cell play at high altitude meaning they have to take precautions.
How did such a harmful condition end up being selected for?
Since the average age of a person with sickle cell is 23, there is enough opportunity for this trait to have been passed on before the person succumbs to the condition. It persists too because this mutant gene gave an evolutionary advantage against malaria (which must have been a strong selection pressure).

Read more here:

https://bleacherreport.com/articles/2716677-footballs-silent-killer-forces-players-and-teams-to-make-tough-choices

Ernest Rutherford

Head shot of Ernest Rutherford

Source: Wikimedia Commons

 

NZ Biography of the Kiwi who split the atom 100 years ago. This book was written by Dr John Campbell, a NZ physicist himself. This link takes you to the written and audio version of the interview with Dr Campbell. . A must for physics and chemistry students!

 

https://www.rnz.co.nz/national/programmes/afternoons/audio/2018709863/nz-biography-ernest-rutherford

Tales from the Periodic Table

If you haven’t been following this series check it out!  Different angles on the periodic table.

https://www.rnz.co.nz/programmes/elemental/story/2018683167/tales-from-the-periodic-table

and `Elemental’

https://www.rnz.co.nz/programmes/elemental 

The `most boring chemical element’  is a great article that highlights some of the quirky sides of the periodic table.

https://www.rnz.co.nz/programmes/elemental/story/2018706628/the-most-boring-chemical-element

Lord of the Rings Fans

Peter Jackson was inspired by the black tunnel web spider of NZ when creating the spider Shelob in the movie trilogy.

close up of black tunnel web spider

Source: Te Papa

https://www.rnz.co.nz/national/programmes/afternoons/audio/2018710092/critter-of-the-week-black-tunnelweb-spider

Nicola Toki of DOC has a weekly RNZ radio spot  `Critter of the Week’ that focuses on a NZ species.

Podcasts on the other species can be found here:

https://www.rnz.co.nz/national/programmes/afternoons/collections/critter-of-the-week

 

Me and the Hive

Friday, September 7th, 2018 | STEPHEN BRONI | No Comments

Me and the Hive

by Jehu Brogden     Stratford High School

Jehu Brodgen head shot

 

Buzz, buzz, buzz. Stay still Jehu, you’re a statue, think calming thoughts3 photos of bee hives like ice cream, like this bee kindly flying away. These were my thoughts as I stood petrified on a summer evening, out beekeeping with my father. As always, I was wondering how the heck my father had talked me into doing this. Sure, their honey is sweet, but their barbed stinger is sharp and there are approximately sixty thousand1 of them. All armed and ready to go. Then I feel it, the soft griping of the insect’s six legs, as it slowly starts to crawl up my overalls. I see it’s “abdomen is abruptly bent downward2” its readying for the sting in the exact moment my body tenses. I feel the hot burning sensation as the barbed dagger enters my body, I know the bee is dead. But I need to run.

Bees may not form an angry storm cloud like we see in films, but they do work together to get rid of a threat to the hive. I run as fast as I can, my legs pumping, and I swear that I have never run so fast in my life. I arrive at home in a world of pain, but thankfully I know what to do. I sprint to the kitchen and seized a packet of sodium bicarbonate (or as I knew it at the time baking soda). Next I quickly removed the stinger as it was still pumping its venom into me (which is composed of 88% water and is acidic with a ph. between 4.5 and 5.53). Once I had done this I spread the paste on thy skin and let out a sigh of relief as I knew that the acid in the venom was being neutralised. This was the first time that I can remember using science, because science to me is not just knowledge but being able to apply this knowledge.

Some days later…

The bees are surrounding us once again with their ugly buzzing, crashing into my bee suit like kamikazes. They have no remorse, just like me at this moment. I was fed up with this queen rearing business. The hives are even more unhappy than usual, although to be honest I can’t blame them. After all we had just split the hive and made it queen-less. But when you are getting stung daily you do start to question your father’s choice in hobbies. At least painting doesn’t hurt.

We quickly took out a frame of brood and returned to our shed. It was time to start grafting. I was nervous at this point because, if I mucked this up then all work we had done in the last week would be for nought. I turned on the cold light and held the grafting tool loosely. It was shaped like a pen but had a spatula at the end. It’s just a game of Operation I say to myself. The goal is to very, very gently slide the spatula down the side of the comb and then gently remove the larvae without rolling or squashing it. Then I had to gently place them into the prepared queen cell. Once I had repeated this 10 more times and placed the frame inside the hive the anticipation mounted, as there would be no way of knowing if any were undamaged. We had to wait 8 days from the time we put them into the incubator till the queens emerged from their cells. We do this to separate the queens because otherwise “should other queens emerge they fight when they meet4”. On the eighth day I found that six queen’s cells had hatched. My father and I were excited as this was my first attempt and his previous try had failed.

Science has helped me and my father because beekeeping relies heavily on observation. This is because first we had to observe the bees’ behaviour to gain the knowledge we needed and then we had to learn how to apply this knowledge. This skill is useful as a lot can go wrong with bee hives including American foul brood, varroa and robbing. The ability to observe the hive’s behaviour and have the knowledge to diagnose the problem is essential to beekeeping and other areas in life.

Sources:

1: Contemporary Queen rearing by Harry Laid Law Jr pg1.
2: The hive and the honey bee collaboration of: E. L. Atkins, R Banker, Dr. C. G. Butler, G. H. Cale, Sr., Dr. G. H. Cttzale, Jr., Dr. E. Crane, C. C Dadant, W. J. Diehnelt, Dr. A. Dietz, Dr. B. Furgala, Dr. N. E. Gary, Dr. T. A. Gochnauer, C. E. Killion, Sr., Dr. E. C. Martin, Dr. E Oertel, J. Powers, Dr. F. Robinson, Dr. W. C. Rothenbuhler, Dr. F. Ruttner, Dr. H. Shimanuki, Dr. R. W. Shuel, Dr. R. E. Snodgrass, W. A. Stephen, G. F. Townsend, Dr. J. W. White, Jr., Dr. P. C. Witherell, and H. F. York, Jr. pg 110.
3: http://www.beeculture.com/bee-venom-chemistry-ouch/
4: Contemporary Queen rearing by Harry Laid Law Jr pg 8.

The Food of Your Future

Wednesday, August 22nd, 2018 | STEPHEN BRONI | No Comments

AquAdvantage Salmon

The Food of your Future

Head shot of student Joe Glancy

 

Joe Glancy​ ​South Westland Area School​ ​(2018)

 

Who doesn’t enjoy a perfectly cooked salmon with a freshly baked loaf of bread. Mmmnnmmm! I know I do! This seafood that we know and love is becoming increasingly popular in our diet, but will it be the same for our grandkids – will it last?

In 1989, research began on the AquAdvantage Salmon which scientists claim can reach market size almost twice as quickly as normal salmon. The creation of AquAdvantage salmon begins with the selection of two DNA sequences: one from a Chinook Salmon ; the other from an eel-like fish called the Ocean Pout.

The Ocean Pout lives in the near freezing waters of the North Atlantic Ocean. The growth hormone gene from the fast growing Chinook Salmon is combined with the antifreeze promoter of the Ocean Pout (a promoter is a sequence of DNA that ‘turns on’ a gene). By genetically joining these two DNA sequences, scientists are able to create a gene that keeps that internal, fast growing, hormone factory switched ‘on’ during those cooler winter months. Something that salmon normally do not do. This means that they can be farmed year-round and in any climate. Resulting in a fish that reaches market size in just 18 months rather than three years for normal salmon. These are the offspring intended for our dinner plates on those warm summer evenings.

This AquAdvantage Salmon is the very first of its kind. Never before has a genetically modified animal been approved for human consumption. In 2015 the United States approved the production, sale and consumption of the AquAdvantage Salmon. Many other GM animals have been developed and tested but politics and public fears have kept them off our dinner plates. The FDA claims that this salmon will have no effect on consumers … that’s you and me … and will look, feel and taste just like a normal Atlantic Salmon, which is what we all want.

The company that produces AquAdvantage Salmon believes in sustainable seafood production. They claim that their product is better for both consumers and the environment. The Salmon will be raised in land based farms, meaning that there is no risk of escaping salmon entering wild populations and no risk of diseases spreading out of containment. All waste water is filtered extremely well and reused; the small amount that is not required is cleaned of all contaminants and used on nearby tomato farms as fertilizer.

GM salmon use roughly 20% less feed then normal salmon, therefore making it a whole lot cheaper to feed them. Also these AquAdvantage salmon are grown in land based systems close to the production factories. This eliminates the cost to transport them to the place where they cut them up. This has created a salmon that is just as tasty as a wild one but costs a whole lot less to produce.
Business man, Brendan Borrell, claims that the normal salmon cost almost $1.50 to make whereas the AquAdvantage Salmon has a cost of less then $1.00!
A major environmental implication of farmed salmon is the increased preservation and protection of wild populations, populations that have been in decline since at least the 1950’s. By eliminating the need of wild salmon commercial fishing and introducing more land based farms, many threats to the wild salmon are removed. Currently these threats include reduced food supply caused by over-exploitation of the salmon feed, parasites
spread by water based fish farms and destructive fishing techniques. By introducing land based systems such as the one used by the AquAdvantage Salmon, the wild salmon will be protected from these threats and be allowed to live their lives largely uninterrupted.

David Suzuki, Canadian academic and environmental activist, feels very strongly about GMO’s. For years he has been promoting outright bans on GMOs, despite the fact that many scientists have declared them perfectly safe for all of you to consume. He and other anti-GMO activists have been able to stall crucial experiments with GM crops that are designed to improve yields and nutrition, which would benefit poor people around the world.

Ronald Stotish, chief executive of AquaBounty, also claims that the main advantage of the salmon is that the fish can be grown in tanks inland, greatly reducing the effects on the environment. “Demand for global protein is increasing,” he says. “We have to do a better job and we have to do it efficiently.”

Personal:

Now then, I know those of you that get out
there and have been to South Westland
Salmon Competition, you will know just
how little fish are around. In fact, just in the last few months, I have been out chasing
salmon on the Waitaha River several  times. Even though I have had no luck recently, I thoroughly enjoy the feeling of a wild salmon fighting with your line. This is a feeling that I strongly want our future generations to experience.

Personally, I am all for the Genetically Modified AquAdvantage Salmon.

From my research, I think that it is an incredibly well thought out process that takes into account all the various viewpoints. I was especially impressed with its environmental impacts. In order for one of the prime cattle beast from your local dairy farm to put on just 1 kg of body weight, it requires 8 kg of food. Whereas a GM salmon needs just 1kg of food to put on 1 kg of body weight. This shows that the salmon is among the most economically sustainable protein source for humans. All of a sudden this GM salmon has become one of the few animals that puts on weight in equal proportions to its feed. However, currently the NZ ministry for the environment does not allow you and I to purchase and enjoy any fresh meat, fruit or veg that is a GM product. I think that they should change their stance on this. If we can convince them to allow the sale of AquAdvantage Salmon here in our hometown, then we would be giving the wild populations of salmon in our local rivers a much better chance of surviving. I am talkingabout the Wanganui, the Waitaha, the Whataroa, the South Westland fishing competition. All of these places will be able to host a larger population of salmon for your future generations to enjoy.

If you are interested in finding out more please take time to look at the
AquAdvantage Salmon home website Aquabounty.com

 

 

 

Reference List:

https://www.biofortified.org/2010/10/salmon/
https://scienceprogress.org/2011/09/the-gmo-salmon-struggle/
https://gmoanswers.com/9-things-you-need-know-about-gmo-salmon http://aquabounty.com/
https://www.fda.gov/AnimalVeterinary/DevelopmentApprovalProcess/GeneticEngineering/GeneticallyEngineeredAnimals/ucm473237.htm
https://pacificwild.org/take-action/campaigns/protect-wild-salmon
http://www.mfe.govt.nz/publications/hazards/gm-nz-approach-jun04/genetic-modification- new-zealand
https://www.organicconsumers.org/news/10-world-organizations-have-taken-stand-again st-gmos
https://geneticliteracyproject.org/2018/05/02/viewpoint-david-suzukis-views-on-gmos-well-outside-the-scientific-mainstream/
https://www.ft.com/content/ab9b81ae-c94e-11e7-8536-d321d0d897a3
https://www.businessinsider.com.au/this-salmon-will-likely-be-the-first-gmo-animal-you-eat-2014-6?r=US&IR=T
https://www.seafoodsource.com/news/supply-trade/aquabounty-sells-first-batch-of-genetically-engineered-salmon

Futuristic Animals from the Past?

Wednesday, August 15th, 2018 | STEPHEN BRONI | No Comments

Futuristic animals from the past? 

Harriett Spoelstra – Ruawai College

 

The enclosure is empty; the dinosaur has disappeared! Scientists are unable to control this creature, this monster – deadly but amazing. We’ve all yelled at the screen as movie characters act dramatically stupid; at the scientists in Jurassic World who create a creature too powerful to control or understand; at the cartoons with the evil scientists who accidentally make a supervillain. This hunger to learn everything, to create something just because you can is what makes these characters so memorable.
Scientists (a term that covers a whole range of people and jobs) have greatly contributed to making the world what it is today, and scientists who have a passion to help and learn about our world are the key to a future that we would like to come true.

What if it were possible to bring back species long extinct?

Let the moa and the mammoth walk again? Or let a dinosaur once more paw the earth, or even make something new move and breathe? That power so often found in books or movies may soon not just be in our heads but in our hands.

New Zealand is a land of paddocks full of sheep, cows and chickens. If we were to
take a look at these creatures in the past, they would look quite different to the
domesticated version we are so used to. Through intensive selective breeding,
domesticated animals have been transformed so they better suit our needs; they
can produce more meat and grow more quickly. Breeding has also been used to
reduce infection and avoid diseases.

paddock with cattle &rainbow

 

Living on a farm myself, I can
easily see how our ideas and
inventions influence the land and
in turn influence our lives. This is
one way we have used scientific
methods in an attempt to create a
world which can better support us.

 

Modifying animals for our own purposes can be a terrifying and controversial concept, but human nature seems to dictate that we will continue to pursue this.

Genetic modification in the lab is different to intensive selective breeding but ultimately both are using science to change animals to suit us. De-extinction is a term that can be misleading, as we wouldn’t be able to bring back a creature that was extinct but rather create a hybrid with a close living relative, and so make a proxy of the extinct species. De-extinction is a concept that seems rather terrifying yet exciting. However, I wonder how different a creature made in this way would be from its ancestors, and I wouldn’t want to create a new creature that doesn’t fit into our world. An animal’s interaction with its environment is what influences its behaviour and quality of life. We may have to give ourselves limits on what we do, for the sake of our ethics; what would be the point of ‘bringing a species back to life’? Where would they live and how would they be able to survive in a world of humans, especially if humankind was a cause of their extinction?

The temptation to bring back species, or even help prevent endangered species from becoming extinct would be very great but I think we should be careful not to try and ‘rule’ over animals but rather do something that benefits the world as a whole and its future as well as humankind, especially when this science is not at all cheap. We may intend to help animal-kind as well as human-kind, but this technology may give us the feeling that we don’t have be proactive in protecting animals because we could always just bring back extinct species at will. Of course, I am talking about extreme circumstances and a future which may be more fitting in a sci-fi movie than reality but a version of this future could be real and may be not so far away.

In a world without science, there would be no new knowledge contributed to society, no inventions; the paddocks dotted with designer cows I see whenever I look out the window would not be possible. Science, and our understanding of it, has developed alongside the development of humankind. It is a part of me and my life, and the life of everyone who has ever wondered how something worked or used a cell-phone, turned on a light, or even just ate food cooked in a kitchen. Through science humans have developed the ability to influence genetic modification for our own purposes and technology is rapidly advancing right at this very moment.

We must always remember that our curiosity and scientific methods have made our present world and will make our future, but just because we have the power to genetically modify animals and humans doesn’t necessarily mean we should.

References
● https://www.nzherald.co.nz/index.cfm?objectid=12039710&ref=twitter
● http://www.dailymail.co.uk/sciencetech/article-3459168/From-giant-GM-salmon-buffed-Belgian-Bluecattle-animals-eat-looked-like-humans-began-breeding-food.html
● https://en.wikipedia.org/wiki/History_of_genetic_engineering

Photo credits:

Video killed the radio star??

Thursday, April 7th, 2016 | EMILY HALL | No Comments

flatscreenThe other day, looking for a quick video on the Science of Sport to show a Physics class as a little starter, I went to the Veritasium website to look for some inspiration. I found these two videos which I think have been posted before but are definitely worth a re visit for Science Teachers.

This is going to REVOLUTIONIZE education! 

Effectiveness of Science Videos 

Just as an aside, I ended up going with this video: Bungy Jumping What I did was show the video to the students as a starter. They watched, I paused it when you need to select an answer. No one was keen to volunteer their answer to the question so I just un paused the video and let it finish. What they didn’t know was that no answer is actually given in the video! So, when the video was over, they HAD to discuss and work it out and talk with each other because they really really wanted to know the answer. SO we ended up having a great discussion on forces in the fall, what is that rope actually doing, we talked about transfer of energy and all kinds of good stuff. I’m definitely going to check out some of the other little starter videos and try and sneak one in again 🙂

 

 

Can Meat Actually be Eco-Friendly?

Wednesday, July 22nd, 2015 | STEPHEN BRONI | No Comments

In a country that relies heavily on agriculture- all be it heavily swayed towards dairy rather than meat production, for now at least- this a question worth investigating.
I came across this article as part one of a series of three articles on the question

Should we eat meat?

Meat in supermarket

Writer, Nathanael Johnson, author of All Natural: A Skeptic’s Quest to Discover If the Natural Approach to Diet, Childbirth, Healing, and the Environment Really Keeps Us Healthier and Happier. looks at this question from 3 perspectives:
• Environmental sustainability,
• Morality,
• Practicality.
In the first of these articles he asks the question
Can meat be sustainable?
You may find some of what he discovered on this topic quite illuminating.

“A frightening and potentially dangerous technology”

Wednesday, May 13th, 2015 | STEPHEN BRONI | No Comments

That was how Otago University Prof Peter Dearden  from Genetics OtagoChinese genome scientist(1) described  a recent paper by a groups of chinese scientists describing the first genetically modified human embryos and opening a route to germ-line modification of our own species.

Check it out  and add your own views to the Sciblogs  comments  page.

Would you be willing to exchange your clothing for plumage?

Thursday, September 11th, 2014 | STEPHEN BRONI | No Comments

Ever heard of  ‘Transhumanism‘?Lucy Glendining sculpture of feathered child

Over the past few years, a new paradigm for thinking about humankind’s future has begun to take shape among some leading computer scientists, neuroscientists, nanotechnologists and researchers at the forefront of technological development.

 “Transhumanism”  is the name for a new way of thinking that challenges the premiss that the human condition is and will remain essentially unalterable.

 `Transhumanists’ say this  assumption no longer holds true. Arguably it has never been true. They argue that such innovations as speech, written language, printing, engines, modern medicine and computers have had a profound impact not just on how people live their lives, but on who and what they are.

What might happen in the next  20, 50, 100 years ?

A new book entitled  the The Proactionary Imperative presents a  the cultural, intellectual and ethical `justification’ for the emerging  transhumanist movement and in so doing paints an ethically  challenging and scary scenario for  the future of the human race?

“Fancy living forever, or uploading your mind to the net? The Proactionary Imperative embraces transhumanist dreams, but reminds why we need medical ethics”.

Calling all Biologists…Chemists…and maybe even Physicists

Tuesday, May 13th, 2014 | STEPHEN BRONI | No Comments

Daniel has posted a great question on  the
Knowledge Forum Biology Curriculum: Human Evolution   Discussion View:LifeSpiral2

Q: What are the best examples in the world today that support the
theory of evolution?

 

I’m putting the challenge out there for you all.

This is a great opportunity to get back into Knowlege Forum with a topic at the heart of the biology curriculum.

Is the evidence all  from Biology? 

If you have forgotten how to log-in   to Knowledge Forum and build on a post we will be putting  up  a  link to refresher tutorial very soon but flick us an email in meantime and we’ll get you in there right away.

PS When you get into the  Knowledge Forum – Biology Curriculum: Human Evolution View you are looking the build-on the post  titled ‘Support’ on the far right of the Discussion View.

Biology resource from OUASSA teacher PD!

Thursday, May 30th, 2013 | EMILY HALL | No Comments

Thanks again to Susan Yardley for her engaging presentation about her Endeavour Scholarship work last night. If you missed the presentation, you can find it here: https://connect.otago.ac.nz/p8ffdabve7k/

Also if you would like to check out the resource she developed, you can find it here: http://www.landcareresearch.co.nz/resources/identification/plants/styx-mill-biodiversity

 

The Dawn of De-extinction. Are you ready?

Friday, March 15th, 2013 | STEPHEN BRONI | No Comments

“Throughout humankind’s history, we’ve driven species after species extinct: the passenger pigeon, the Eastern cougar, the dodo … A colour collage of threatened species

But now, says Stewart Brand, we have the technology (and the biology) to bring back species that humanity wiped out. So — should we? Which ones? ”

Check out  Stewart Brand’s TED  Talk here at

http://www.ted.com/talks/stewart_brand_the_dawn_of_de_extinction_are_you_ready.html 

 Is it the answer to every conservationist’s prayer?

Or,
As Barry Hillman  muses in  on one of  the responses,
“Sure, we have a responsibility to un-do the damage we’ve done,let’s try to change our thinking and become a more caring society that has no need to damage our world and then we can spend more of our valuable and limited time on earth creating instead of repairing.”

What do you think? 

There’s a follow-up here, a panel video discussion `hot off the  press’  from March 15th  :  http://tedxdeextinction.org/ 

(OUASSA students: You can now comment on our Blog-posts,  but after clicking ` Comment’ box, you will have to sign-in using your Otago University login given  to you at the January camp)

I had to get up anyway…

Tuesday, February 12th, 2013 | EMILY HALL | 1 Comment

This morning my lovely 11 year old nieces woke me up from a dead slumber with a 5am facetime request. I can forgive them because they live in Canada and don’t really have a handle on time differences. Of course their first question was “why is it so dark?” since for them it was 10am and daylight…

Anyway – I have been thinking about sleep lately because the latest issue of New Scientist covers the issue of sleep in depth. Recommended reading if you can get your hands on it. While thinking about sleep I also spent some time here warning though there are so many interesting interactive things to play with you could end up spending more time than you planned!

Finally nothing to do with sleep but I recently received an email with a link to the Quantum World song from this website. I watched a couple of the other ones and thought they were pretty neat. The planets one is good, and not just because Neil de Grasse Tyson is wearing a super funky tie in it. I have put the link to the Climate Change one on Knowledge Forum under the Climate Change question. They’re all worth a look though if you have a spare few minutes – maybe some soothing science music if you’re having trouble sleeping?

Avian Influenza: H5N1 Researchers Ready as Moratorium Nears End

Friday, January 4th, 2013 | STEPHEN BRONI | No Comments

 “Just because we can does it mean we should?”

Researchers who study the H5N1 avian influenza virus will soon be able to do some science that’s been off-limits for nearly a year.

This has sparked  renewed debate on the dangers of developing a strain that  can move between mammals.
Fearing that such “gain-of-function” experiments could enable terrorists or a lab accident to start a deadly human pandemic, critics demanded stricter controls on science that could be used for good and evil.

Read on for the full story on how scientists globally are trying to address this issue.  http://www.sciencemag.org/content/339/6115/16.full

The Fish With A See-Through Head

Friday, October 19th, 2012 | STEPHEN BRONI | No Comments

 

Macropinna Microstoma: The Fish with a  See-Through HeadPhoto of deep sea fish (Macropinna Microstoma) with a transparent head

Every once in a while  (well, actually more often  than you might think) nature comes up with something so bizarre  it leaves you shaking your head and  pondering  “How? How? How?” and  puzzling  “Why? Why? Why?”

Found 600m or more down off the coast of California, the species lives in nearly total darkness. A transparent fluid-filled sack replaces the top of the head and two spots above the mouth, called nares, act somewhat like human nostrils, chemically sampling the water.

Experts think the fish hangs motionless in the current with its eyes swivelled upwards to spot the faint silhouettes of its prey. If it spots something it likes the look of, it rolls its eyes back to the forwards position and swims up to intercept it with its small, toothless mouth.

Check it out on this short video clip

Macropinna microstoma A deep-sea fish with a transparent head and tubular eyes

So, what’s the evolutionary advantage of a see-through head?
Would you want one for yourself?
( Might make wearing a beanie compulsory for some of us!)

Nobel Prize for Physiology or Medicine 2012: stem cell research

Tuesday, October 9th, 2012 | smida55p | No Comments

This year’s Nobel Prize for Physiology or Medicine goes to two researchers for their work on induced pluripotent stem cells or IPSCs.  The Prize recognises the achievements of the two researchers in this promising field of science – one of whom first published on the subject 50 years ago.

IPSCs are formed from mature body cells that have been effectively ‘reprogramed’ to a pluripotent state so that they resemble the cells in an early embryo.  Early embryonic stem cells are pluripotent and so have the highest potency of any stem cells.  This means that (under the right conditions) they are able to develop or differentiate into any type of cell.

Many medical researchers think that stem cells have a lot of potential for therapeutic uses such as tissue repair, regeneration and replacement, as well as providing a source of human cells for experimentation, investigating cellular processes and modelling the action of drugs.  Early research into pluripotent stem cells involved the use of early human embryoes.  IPSCs are of significant interest in medical science as they could provide pluripotent stem cells from a non-embyronic source.

Read about this exciting story of stem cell research at http://www.sciencedaily.com/releases/2012/10/121008082955.htm

Clambake Extinctions, Volcanic Deccan Pies & Demise of Dinosaurs

Friday, September 14th, 2012 | STEPHEN BRONI | No Comments

“Most researchers think the dinosaurs, many plants on land, and much of the life in thePainting showing dinosaur in landscape and comet hurtling through sky above sea succumbed to a huge cosmic impact 65.5 million years ago. But new evidence from the sea floor just off Antarctica points to a major extinction there a geologic moment before the impact. The culprit in this earlier cataclysm may well have been humongous volcanic eruptions in India—the same eruptions that some researchers have credited with wiping out the dinosaurs.”

Read the full story here
http://www.sciencemag.org/content/337/6100/1280.full

Gene mutation events linked to ‘milestones’ in human evolution

Wednesday, August 29th, 2012 | smida55p | No Comments

In the third online OUASSA biology tutorial I introduced the idea that a type of chromosomal mutation known as gene duplication may be important in “providing evolution some spare genes to play with”.

Many scientists think that gene duplications have contributed to some evolutionary changes, from the evolution of antifreeze proteins in polar fish (http://www.sciencedaily.com/releases/2011/01/110112122511.htm), the divesification of a group of calcium binding polypeptides in vertebrates that are important in tooth and bone formation and production of milk and salivary proteins in mammals (http://www.frontiersinzoology.com/content/2/1/15), to the evolution of true trichromatic colour vision in African apes. (http://anthro.palomar.edu/primate/color.htm; http://www.ncbi.nlm.nih.gov/pubmed/10413401).

A lovely example of the role of gene duplication in evolution for Level 3/Scholarship Biology – that is truly relevant to us all in the widest possible sense – can be found at http://www.newscientist.com/article/dn21777-the-humanity-switch-how-one-gene-made-us-brainier.html.  This article tells the story of how the repeated duplication of a gene involved in neural development may have been involved in two major advances in brain cell organisation and thinking power that correlate with some big leaps forward in our own biological evolution.  Enjoy!  Darren.

Ever wondered how we know so much about genetics? “DNA from the Beginning” tells the stories of the experiments behind the biology.

Thursday, August 16th, 2012 | smida55p | No Comments

“DNA from the Beginning” is a fantastic resource that tells the stories of the science and scientists  that have helped to build our knowledge of DNA and genetics:

Explore http://www.dnaftb.org/

It is packed with great animations, stories, activities, quizzes and summaries of key concepts, and is ideal for anyone studying 90715 “Describe the role of DNA in relation to gene expression”.  10/10! – Darren

Great resource for Processes and Patterns of Evolution

Thursday, July 19th, 2012 | smida55p | No Comments

This is a one of my favourite websites for simple, clear and valid content for learning about evolutionary processes and patterns from Berkeley:

http://evolution.berkeley.edu/evosite/evo101/index.shtml

Heaps of wonderful images, explanations and examples for revision or note-taking.

Revenge of the Weeds

Friday, June 22nd, 2012 | STEPHEN BRONI | No Comments

Plant pests are evolving to outsmart common herbicides, costing farmers crops and money

“It’s a story suited for a Hollywood horror film, yet it’s also a tenet of evolutionary biology. Introduce a toxin to a system, and you inevitably select for resistant survivors. These few individuals gain a reproductive advantage and multiply; sometimes they can’t be stopped with even the most potent chemicals.”

Read on for some sobering thoughts:

http://the-scientist.com/2012/05/20/revenge-of-the-weeds/

NZ International Biology Olympiad Registration, Now Open!

Monday, June 11th, 2012 | hamvi58p | No Comments

 In 2014, New Zealand will be hosting the 25th International Biology Olympiad: the world’s top biology educators and secondary school biology students will converge on the University of Waikato for a week of intense academic effort – but there’ll also be time for making new friends, sharing ideas, and experiencing some of what New Zealand has to offer. “The lead-up to this event will involve a huge amount of work,’ says NZIBO Chair Dr Angela Sharpies, “and we’re very keen for more teachers and academics to join the NZIBO committee and become involved with this awesome event.”
On-line registration for the 2013 NZIBO programme is now open at www.nzibo.org.
For students whose schools have never participated in NZIBO, the fee is $15 per student, while the cost for students from schools that have been involved is $30.
All Year 11 and Year 12 biology students are encouraged to enrol.
Registrations close on the 1st of August and the entrance exam will be held in the fourth week of Term 3 on Wednesday August 8, 2012.
The two hour long, multi-choice exam consists of a series of questions designed to test students thinking and problem solving skills.
The NZIBO programme is an excellent opportunity for Gifted and Talented biology students.
Following the initial exam, approximately 60 students will be invited to enter the tutorial programme.
Full details of the scheme with costs can be found on the NZIBO website.
In 2013, the International Biology Olympiad will be held in Bern, Switzerland. For further information, please contact the NZIBO secretary, Dr H Meikle, at: nzibo.register@gmail.com.
Jessie McKenzie Teaching and Learning Specialist——————————————————————————————The Royal Society of New ZealandDDI: +64 4 4705 789 | MOB: +64 21 254 9114 |  SKYPE: jessie.mckenzie.rsnz 4 Halswell Street, Thorndon, PO Box 598, Wellington 6140, New Zealandwww.royalsociety.org.nz

New OUASSA Staff Member

Friday, June 8th, 2012 | STEPHEN BRONI | No Comments

Hi everyone

My name is Darren Smith.

I’ve just joined the OUASSA team and will be helping out Kate and Steve for the rest of the year.

I’m a biology teacher and the sea has always been my playground, passion and study – and has been since I was old enough to gut a fish and focus a microscope. I have a Masters degree in marine biology and have worked on science research projects looking at the effects of nutrient enrichment on coral reefs and fishing impacts on seafloor communities. I’m also really into sharks, but hopefully not as a potential prey item!

I’m here to help you get the most out of your OUASSA experience and am really looking forward to reading your posts on Knowledge Forum and helping you find the answers to your biology curriculum questions. I’ve been following your progress on KF and have made a few posts on the Marine Science Project A, so maybe take an opportunity for a look. 

See you all soon at the July OUASSA camp for an awesome week of fun, challenging and rewarding science!

Knowledge Forum: Synthesis of Project A Discussion Views

Tuesday, May 15th, 2012 | STEPHEN BRONI | No Comments

 Hi  All
Your task is a simple one:
You are each to make to a New Note that pulls together the knowledge you have gained from the knowledge building discussion on your Project A View (Maths, Physics, Marine Science or Zoology). 

We have added a new set of scaffolds entitled ‘My Synthesis’ to help you do this.

Use these scaffolds to help you synthesise what you have learned from your Project A discussion and to highlight the ideas, posts and links that helped your knowledge building most. 

Post your synthesis as a New Note titled `My Synthesis’ within your Project view.

This task should take you no more than 30 minutes.

Date Due:  Fri 25th of May

We look forward to reading your ‘My Synthesis’ post. 

Don’t forget if you have ANY technical problems using Knowledge Forum let us know right away.  For those of you who haven’t been in for a while, have forgotten how to use the software or have lost the starter guide given you at the January camp, we are happy to  email you another copy and/or run a short refresher on-line using OtagoConnect.

Soon we will be posting the Project B views (Chemistry, Biochemistry/Genetics, Computer Science and Geography) to create an on-line discussion and to synthesize ideas generated between now and the July camp. 

May we take this opportunity to remind you that we expect you to access Knowledge Forum at least once a week to read the posts of others and to make a new note. This is your contribution to the Academy between camps and is part of  the  commitment  you undertook when you applied to The OUASSA.

Don’t forget the Curriculum Views are there  to post questions asking for advice or assistance with internals and externals etc. We will gladly help where we can!

Science Alert – Website

Tuesday, May 8th, 2012 | hamvi58p | No Comments

An excellent website with the latest news and research developments.  http://www.sciencealert.com.au/  There are many great articles to read and links to follow…. here is an example of a good article about human endogenous rhythms and the potential role of the liver.  All of you Y13 Biology students will be studying biological timing mechanisims in preparation for the external AS ‘Describe animal behaviour and plant responses in relation to environmental factors’.

Liver helps ‘set’ body clock

The University of Sydney
Friday, 04 May 2012
A disrupted body clock can cause a higher risk of obesity and diabetes, but this breakthrough suggets a new target for treatments to ‘reset’ the clock.

International travellers, shift workers and even people suffering from obesity-related conditions stand to benefit from a key discovery about the functioning of the body’s internal clock.
Professor Chris Liddle, from the Westmead Millennium Institute for Medical Research, the University of Sydney, worked with a team from the Salk Institute based in California, to demonstrate the importance of circadian receptors found in the brain and the liver. Their findings are published in Nature today.
“The research is important as these are the first core component of the circadian clock identified that can be targeted with drugs, which could provide relief for those affected by disrupted circadian rhythms,” said Professor Liddle.
The circadian clock is an internal daily body clock that controls alertness, appetite, sleep timing and hormone secretions.
“Previously we have known that there are body ‘clocks’ not only in the brain but in most other body tissues including the liver, part of the focus of this study. While the brain clock is mainly cued by light, these other clocks are cued by factors such as exercise and diet as well as receiving nerve and hormone signals from the central clock in the brain.”
People with circadian disturbances tend to have a higher incidence of health concerns such as obesity, diabetes and related metabolic disorders. It is much more than simply a problem of disturbed sleep.
“People tend to think that the clock is just something that happens in the brain but it’s a whole-body issue. Literally you do not feel like exercising and your metabolism slows when you are in a certain part of the cycle. This contributes to obesity-related problems.
“When you fly overseas, not only do you wake up in the middle of the night, you probably notice you want to eat in the middle of the night, and that during the day you have reduced energy. The liver is a key player in the regulation of energy and we now understand quite a bit more how liver genes ‘clock in’ to the circadian cycle.”
Professor Liddle, a liver expert who has worked on liver genes for more than a decade with the Salk Institute, said the team had been able to show that these receptors in the liver were important in controlling the metabolism of fats and other genes related to diet, nutrition, digestion and energy expenditure.
“This is a very exciting discovery. We have now shown that these receptors in the body’s tissues do not have a peripheral role but are core components for setting our body clock that we can potentially use drugs on.
“The promise of this research for the future is that we can specifically target drug treatments at these receptors. The hope is that not only problems like jet lag and disturbed sleep can be more easily managed but other associated health concerns can be addressed more effectively,” Professor Liddle said.

Maui’s dolphins’ survival near ‘point of no return’

Monday, April 30th, 2012 | hamvi58p | No Comments

Maui Dolphin

CLOSE TO EXTINCTION: A Maui dolphin and her calf.
The survival of the critically endangered Maui’s dolphin species will soon be “past the point of no return” unless emergency action is taken, an expert says.

What is believed to be a Maui’s dolphin was found dead by a member of the public in Taranaki last week. The dolphin was found on a beach near Pungarehu, south of New Plymouth.

It was collected by the Conservation Department and taken to Massey University for an autopsy.

It is not yet known if the dead dolphin is a Maui, of which only 54 are believed to be left, or a closely related Hector’s dolphin. The latest population survey found a couple of Hector’s mingling further north than usual with Maui’s dolphins.

If confirmed, it would be the second Maui’s dolphin found dead in Taranaki this year. Another, a female, was accidentally killed by a fisherman in January.

Otago University zoology professor Liz Slooten said the species was at a level where any loss would have a huge impact.

“Basically all bets are off already, natural processes could take them away. If we stopped catching them in fishing nets tomorrow we would still hold our breath … so we really need to pull out all the stops or soon we’ll go past the point of no return.”

Set net bans are imposed on the coastline between Dargaville to north Taranaki.

“As a biologist it’s really frustrating. I’ve done surveys there and wrote an article in 2005 to say the Maui is going much further south than the protected area,” Prof Slooten said.

The Fisheries Act included allowances for emergency protection measures to be put in place “literally overnight” in cases of sudden stock declines or unprecedented events, she said.

Submissions on laws to further protect the Maui’s dolphins closed on Friday. The laws want to extend the current ban on set nets along the west coast of the North Island and also extend a marine mammal sanctuary.

The fishing industry will argue against the ban, saying the dolphins have not been seen in the Taranaki area for years.

Keith Mawson, of Egmont Seafoods in Taranaki, earlier told the Seafood Industry Council that a proposal to extend the set net ban was a knee-jerk reaction. A ban would be disappointing for the fishing community, which was being used as a “scapegoat”, he said. By Michelle Robinson and Shane Cowlishaw.

– © Fairfax NZ News

101Science.com

Tuesday, April 17th, 2012 | hamvi58p | No Comments

http://101science.com/

This website has a huge quantity of resources and links to some really fasinating sites.  This site would be a good go-to site for background science reading, information gathering and for studying just some of what you will be covering in your classes.

The site covers Biology, Chemistry, Physics, Maths, Electronics and even Photography.

Cell Animation – TED

Monday, April 16th, 2012 | hamvi58p | No Comments

http://www.ted.com/talks/david_bolinsky_animates_a_cell.html

This is a very iinteresting clip from the TED talks. Interesting for keen biologists and students with an interest in garphics, animations, etc.

Medical animator David Bolinsky presents 3 minutes of stunning animation that show the bustling life inside a cell.

David Bolinsky and his team illustrate scientific and medical concepts with high-drama animation. You’ve never seen the life of a cell quite like this.

Each of us has about 100,000 [kinesins] running around, right now, inside each one of your 100 trillion cells. So no matter how lazy you feel, you’re not really intrinsically doing nothing.” (David Bolinsky)

Was Human Evolution Caused by Climate Change ?

Wednesday, April 11th, 2012 | STEPHEN BRONI | No Comments

Neanderthals at the cave site of Trou Al'Wesse in Belgium, clinging on as climate deteriorated. (Credit: Digital painting by James Ives)

Neanderthals at the cave site of Trou Al'Wesse in Belgium, clinging on as climate deteriorated. (Credit: Digital painting by James Ives)

Although an African origin of the modern human species is generally accepted, the evolutionary processes involved in the speciation, geographical spread, and eventual extinction of archaic humans outside of Africa are much debated. An additional complexity has been the recent evidence of limited interbreeding between modern humans and the Neandertals and Denisovans (a newly discovered group from Siberia). Modern human migrations and interactions began during the buildup to the Last Glacial Maximum, starting about 100,000 years ago. By examining the history of other organisms through glacial cycles, valuable models for evolutionary biogeography can be formulated. According to one such model, the adoption of a new refugium by a subgroup of a species may lead to important evolutionary changes.

   “Ultimately, this model explains why Homo sapiens as a species are here and the archaic humans are not.” Dr J.R. Stewart

The research also leads to interesting conclusions as to how and why Neanderthals, and indeed the Denisovans, evolved in the first place.

Check out the full article here

http://www.sciencemag.org/content/335/6074/1317.full

New study says ancient hominid males stayed home while females roamed

Friday, March 16th, 2012 | STEPHEN BRONI | No Comments

The males of the two bipedal hominid species that roamed the South African savannah more than a million years ago were stay-at-home kind of guys when compared to the gadabout gals, says a new high-tech study led by the University of Colorado Boulder. Dr Petrus le Roux from the Department of Geological Sciences at UCT was part of a team which studied teeth from a group of extinct Australopithecus africanus and Paranthropus robustus individuals from two adjacent cave systems in the Sterkfontein-Swartkrans area in South Africa.

hominiid skullThe research team used high-tech laser ablation mass spectrometry to measure isotope ratios of strontium in the hominid tooth enamel in order to identify specific areas of landscape use. A naturally occurring element, strontium, is found in rocks and soils and is absorbed by plants and animals and becomes incorporated in the enamel of their teeth during development. Since unique strontium signals are tied to specific geological substrates – like granite, basalt, quartzite, sandstone and others, they can be used to reveal landscape conditions where ancient hominids grew up Sandi Copeland, UC Boulder Adjunct Professor and lead study author explains, “The strontium isotope ratios are a direct reflection of the foods these hominids ate, which in turn are a reflection of the local geology”. The researchers found that the strontium isotope signals in half of the female teeth indicated that they were derived from outside the local area, which contrasted with that of the males. In the latter only about ten percent suggested that they were from elsewhere, implying that the males probably grew up and died in the same area. Sandi Copeland said, “One of our goals was to try and find something out about early hominid landscape use. Here we have the first direct glimpse of the geographic movements of early hominids, and it appears the females preferentially moved away from their residential groups.” She said that the new study results were somewhat surprising as they had assumed that more of the hominids would be from non-local areas, as it is generally thought that the evolution of bipedalism was due in part to allow individuals to range longer distances. “Such small home ranges could imply that bipedalism evolved for other reasons”, Copeland said.

Professor Matt Sponheimer, UC-Boulder anthropologist and a co-author of the article, says, “It is difficult enough to work out relations between the sexes today, so the challenges in investigating the ways that male and female hominids used the landscape and formed social groups over a million years ago, are considerable. Disembodied skulls and teeth are notoriously poor communicators, so the real difficulty with a study like this is finding new ways to make these old bones speak”. The female dispersal pattern seen in the two hominid groups is similar to that of many modern humans, chimpanzees and bonobos, but unlike most other primates, including gorillas, where one or two males dominate a group of females, explained Copeland. “This study gets us closer to understanding the social structures of ancient hominids, since we now have a better idea about the dispersal patterns”, she said.

From:

Contact: University of Cape Town, Faculty of Science Newsletter, March 2012, Page 11

Studyit!

Friday, March 16th, 2012 | hamvi58p | No Comments

New Zealand’s most popular student website turned eight on 1st March. Studyit www.studyit.org.nz began supporting NCEA students on March 1 2004. Studyit is a free, safe and successful online support site developed and managed by CWA New Media, a business unit of Learning Media.
Studyit has everything needed to get achieve, merit and excellence, written in student
terms, as well as fourteen very active forums where expert teachers answer student questions at night, in the weekends and during holidays.
Recent feedback from Studyit students includes:
  • I got straight E’s in maths, thank you very much for all your help on this website, it really helped me
  • I just wanted to say a huge thanks for all the help I received from Studyit for my level 1 papers last year (I got 100% excellence!)
  • Studyit made a huge difference to the way I approached the exam! I tried to make my answers biologically detailed but concise even though I was really stressed for time.
  • Seems that all us Studyit users found the exam went incredibly well even though 3 News said it was really hard. I think this just goes to show the positive impact of Studyit on our performance
  • I went into the exam feeling a lot more confident knowing that I had prepared as well as I could – and a great deal of that preparation could not have been done without Studyit. It was so great to have such quick replies to all my questions, even on weekends and holidays.
Studyit gives students more confidence!

www.studyit.org.nz for NCEA maths, science and English students.

Studyit facebook
Winner of the 2008, 2009 & 2010 Net Guide People’s
Choice Award for Best Education Site
and
2011 Best Student Site
Winner of the 2006 TUANZ Education Innovation of
the Year Award
Finalist 2011 Australia and New Zealand Internet
Awards

CWA – a business unit of
Learning Media Ltd.
Email: ashley@cwa.co.nz
Mobile: 027 227 8603
Fax: +64 4 382 6509
Web: www.cwa.co.nz
Postal: PO Box 19090, Wellington, New
Zealand

Excellent Revision Site for Chemistry, Physics & Biology!

Monday, March 12th, 2012 | hamvi58p | 1 Comment

Many of you may already be using this site, but it you are not, then I thoroughlly recommend taking the time to have a look around and print off some of the useful resources within.

Site:  http://www.nobraintoosmall.co.nz/

There are flash cards, revision activities/notes, test yourself activities and powerpoint presentations etc.  The site has been created and is maintained by a group of NZ high school teachers with knowledge and expertise in the NZ curriculum as well as NCEA.

You could even recommend this site to your subject teachers as they too would find it useful.

Struggling with Genetics?

Wednesday, March 7th, 2012 | hamvi58p | Comments Off on Struggling with Genetics?

This link is to a website from the University of Utah.  It covers the basics of Y12-Y13 Genetics and covers such topics as ‘What is DNA? What is a chromosome? What is a protein? What is Heredity? What are traits?’ etc

The pace is slow enough that you can make your own notes during the animation or you can simply click through frame by frame and work at your own pace.

There is also a link to ‘What is Meiosis and Mitosis?’ that many of you will find useful to cement these concepts.

http://learn.genetics.utah.edu/content/begin/tour/

What motivates you as a scientist?

Monday, March 5th, 2012 | hamvi58p | No Comments

To tie in with the latest Nature Outlook, Lenses on Biology, the Nature Communities team asked five biological scientists at different stages of their education or careers to tell their personal stories in a guest blog post. Each scientist studies, works or has an interest in one of the five research fields featured in Lenses on Biology ― cancer, stem cells, synthetic biology, ocean health and climate change ― and they share what motivates them in their chosen subject. You can read their stories below, and discuss your own motivations here or on the posts in question.

http://blogs.nature.com/naturejobs/2012/03/02/what-motivates-you-as-a-scientist#wpn-more-152

Revision website ‘S-cool’

Monday, February 20th, 2012 | hamvi58p | No Comments

http://www.s-cool.co.uk/a-level

High quality revision materials using S-cool’s straight forward 3 steps to success process.  This site is from the UK and has a sepcific section for A-level revision (Senior Science).  Each of your classroom subjects will be found on this website.

1. Revise it

Check you know the main principles by reviewing the list of different topic areas, either click on the topic heading to quick learn the whole topic or pick individual principles to brush up.

2. Test it

Now you have learnt the main principles, test yourself with these sample questions. If you get stuck, go back and review the principle again.

Exam style questions

3.  Remember it

Print these out and carry them with you!

 

ESA Study Guides and Revision Books

Friday, February 17th, 2012 | hamvi58p | No Comments

Below is the link to the ESA Publications website.  Hopefully all of you will be focussed on achieving to the very best of your ability at the end of the year and during your internal assessments.  These books offer great support for a vast number of subjects at Y13 level.   They are useful for end of topic tests also and have full vocab lists for all of that tricky terminology (especially useful for Bio!). I highly reccommend these books as a useful support tool.

http://www.esa.co.nz/?type=catalogue-books&page=61&where_type=0&where_year=13&where_subject=all

Essential Readings for Level 3 Bio Externals

Wednesday, October 5th, 2011 | hamvi58p | No Comments

http://www.becominghuman.org/

->Covers human evolution, this website has excellent video coverage and resources

site applying genetics to examples

http://learn.genetics.utah.edu/

->Genetics applications, an excellent site

http://dnalc.org/home.html

-> Gene Almanac, an awesome interactive

http://dnaftb.org/dnaftb/

-> DNA from the beginning, an excellent summary of level 3 genetics

http://www.dnai.org/

-> DNA Interactive, excellent case studies as applications of genetic practises and processes, an awesome site with case study approaches to assist in exam prep (especially for schol exam).

http://sci.waikato.ac.nz/evolution/index.shtml

->  NZ evolution examples, excellent site for evolution with lots of good NZ examples.

http://www.sciencecases.org/hemo/hemo.asp

-> Inheritance of haemophilia, an interesting case study, good practice for thinking.

http://www.biotechlearn.org.nz/

-> NZ science research, home grown examples of applications of science, a good site.

http://www.rsnz.org/education/gamma/

->Royal Society of NZ webiste, Gamma Series, Science behind the news, great articles modelling good writing.

http://www.nzqa.govt.nz/scholarship/index.html

-> scholarship information, details of scholarship, an essential for scholarship candidates.

http://www.nzqa.govt.nz/scholarship/subjects/resources.html

-> Biology Scholarship Information, details of exams etc, an essential for scholarship candidates.

http://www.tki.org.nz/r/ncea/bio3_supportmaterial_15feb06.doc

->NCEA on TKI supplementary materials, summary of genetics and evolution at level 3

http://www.tki.org.nz/r/ncea/bio3_supportgenetics_18dec06.doc

->NCEA on TKI supplementary materials, summary of Plant and Animal and ecology knowledge required for level 3 and scholarship

 

Scholarship support material

Wednesday, September 28th, 2011 | hamvi58p | No Comments

Hi there,

We hope everything is going well and that you are gearing up for your externals in November.  If you are after scholarship support material in Bio/Chem/Physics and Math we can arrange access to the support material provided through Otagonet.  You can access this material whenever you want and can work through a vast array of very useful resources/activities/readings and questions.  Simply email me (Kate) at ouassa@otago.ac.nz and she will sort your log in and password details.

We are also in the process of arranging on-line tutorials for those of you after some extra support using OtagoConnect software.  We will email you with details soon, alternatively email me and let me know if you are interested.

Keep up the good work,

Kate

Kahn Academy

Friday, September 16th, 2011 | hamvi58p | No Comments

This site has a vast number of resources covering much of your Y13 curriculum content… Physics, Chemistry, Biology, Maths (Calc and Stats) etc.  Useful tutorials to watch when you are sick of writing out your own study notes etc and just want to keep learning….

http://www.khanacademy.org/

Biology Scholarship link

Friday, September 2nd, 2011 | hamvi58p | No Comments

You’ll obvioulsy know by now if you are doing Biology Scholarship at the end of the year.  If so, as you’ll know already your best preparation is to read as widely as possible on all things biology related.  Here is the link to guidelines and exemplars from the NZQA website.

http://www.nzqa.govt.nz/qualifications-standards/awards/scholarship/scholarship-subjects/scholarship-biology

Also, as mentioned in an earlier post, the website that I would most recommend to teachers and students alike is the Teachers Domain site:  http://www.teachersdomain.org/collection/k12/sci/.  Make some time to have a look at the resources for wider reading, animations, powerpoints etc on all manner of science related topics.  This site will really help you with developing wider thinking skills to get your responses in exams up to that Merit and Excellence level that you are all striving for!

Tell your science teacher about the Teachers Domain site and this OUASSA site and make their day!

Isolating Mechanisms

Tuesday, August 16th, 2011 | hamvi58p | No Comments

http://www.teachersdomain.org/resource/tdc02.sci.life.evo.lacewings/

Check out the section called ‘Background Essay’….. brilliant for your revision, here is a sneak peak.

‘When explaining a breakup, couples will often say, “We grew apart,” or “We both changed in different ways.” That’s a good metaphor for how species are formed: members of a population somehow begin to diverge, usually as a result of being geographically separated from each other. Eventually, they can no longer interbreed, and at that point a new species has formed.

Yet if the two groups continued to live near each other, it’s likely that mating attempts between naturally varying members of the two populations would tend to allow the species to merge again. This is called “gene flow” between the two groups. What keeps this from happening, and what allows new species to arise and endure, are what are known as “isolating mechanisms.” These are either behavioral or structural differences between species that make mating impossible……’ see website for remainder of article.
Discussion Questions:

  • How might different songs keep species of lacewings from interbreeding?
  • Can you think of other examples of traits or mechanisms that would similarly isolate other closely-related species?

    • Speciation resource –

    Tuesday, August 16th, 2011 | hamvi58p | No Comments

    The Origin of Species

    This is a great website for those wanting to apply themselves to what has been taught in the classroom.  The extract below is the background reading, there are applictaion questions as well as the interactive slide show.  A must for serious Biologists and Excellence/Schol. candidates!

    http://www.teachersdomain.org/resource/tdc02.sci.life.evo.anorigin/

    The term evolution refers to the cumulative change that occurs in populations of organisms over time. Sometimes evolutionary change is so dramatic that different populations of the same species diverge to become two or more distinct species. In the case of a group of birds called honeycreepers, for example, a single species that colonized the Hawaiʻian Islands about 5 million years ago ultimately diverged into 57 different species.

    This process, which evolutionary biologists call speciation or adaptive radiation, can happen anywhere. However, it is most clearly demonstrated on geologically young land masses, such as newly formed islands or mountains. In these environments a population of organisms will typically find a set of environmental opportunities and pressures very different from the conditions they experienced in their place of origin. These environmental differences come in many forms and often cause sweeping evolutionary changes in a founding population.

    Several environmental factors affect the process of speciation. The structural habitat of an area determines the ease with which creatures are able to move around and find shelter from weather and other organisms. Food, both the type and its availability, dictates the ease with which animals are able to acquire the energy they need to survive and reproduce.

    Competition for various resources is another factor that can drive the process of speciation. Competitive pressure can come from organisms of the same species or from organisms of different species. Generally, in highly competitive environments, traits that minimize competition — traits that, for example, allow two different populations to feed on very different types of food — are advantageous.

    Another factor that can influence speciation is predation. Predators typically reduce the rate of speciation because they limit other organisms’ access to resources. On newly formed land masses, however, the number of predators is typically lower than on older continents. These younger environments, therefore, provide more opportunities for species to evolve into new and different species

    ‘Out of Africa’ Hypothesis: Radio Interview

    Sunday, August 7th, 2011 | STEPHEN BRONI | No Comments

    Rebecca Cann   is “Professor of Cell and Molecular Biology, and member of the International Scientific Advisory Panel of the Allan Wilson Centre for Molecular Ecology and Evolution. She co-authored the influential study which showed modern humans evolved from a single African population”  but there is a strong Otago University link through  Professor Alan Wilson  way back in 1950’s. Check out the story on national radio podcast from Sat 6th Aug  at 9.05 am http://www.radionz.co.nz/national/programmes/saturday  

    Zoology Students

    Tuesday, July 12th, 2011 | hamvi58p | No Comments

    Lisa and the Zoology Team have asked that the Zoology students read through the following information prior to their project work.

    Dear Zoology students

    You will find some activities attached here to help prepare you for the Zoology project during this camp. We will be focusing on invasive species, in particular species found within urban areas. As I’m sure you are all aware, this topic can be quite emotive, particularly when addressing issues of impact on native communities and management and control methods. We have asked you to research a couple of questions related to invasive species, gather some viewpoints on invasive species and control, and then finally to do a bit of research into a specific role. At the end of the project we will be undertaking a role play activity where you will be taking on a specific persona and have to argue your case for control. We do realise that the role you are assigned may not reflect your own personal view point, but sometimes they are actually the easiest to argue! 

    Just a reminder to make sure you bring warm clothes, sturdy boots and a torch or headlamp for our early morning excursion on the tuesday. Remember its COLD in Dunedin and snow is predicted this week already.

    Looking forward to working with you all again.

    The Zoology team.

    Questions to think about over the holidays

    There are many introduced species in New Zealand:  >2,000 plant species, 32 mammals, and 33 birds have been introduced. But not all of them are considered to be invaders.

    Can you think about the following, and be prepared to discuss when we meet.

    1. What is the definition of an invasive species?

     

    2.    What makes an invasive species a pest?

    Here are two quotes about possums: think about the implications of these different viewpoints of possums and be prepared to discuss them.

    1.            This quote is by S. Bracegirdle of Egmont Skins and Hides, in the Taranaki Daily News (June 2011), describing his business which collects dead possums, plucks them for fur to sell to wool factories for possum/wool garments:

     “We’re turning a pest into something creative” 

    2.            This quote is by Potts (2009, Society and Animals Vol 17: pp 1-20):

    “Possums are positioned not only as unwanted and dangerous foreign invaders but also as unworthy of compassion and deserving of persecution: it is as if possums are responsible for the prejudice and malice they now face”

    Finally, please gather three viewpoints from your family or acquaintances on possums as pests and their knowledge of current methods of possum control.

    1.

    2.

    3.

    Role Play Exercise

    Management and control of invasive species is often a very emotive subject resulting in a wide range of very different viewpoints. It is important that we consider all of these different views when  planning and implementing management programmes. This exercise is designed to give you an opportunity to explore some very divergent view points.

    Scenario:

    It has been proposed by a group of local environmentalists that an area of land, which includes a cluster of farms (some dairy), significant remnants of native vegetation, and including some small urban areas, be managed to be predator-free with the purpose of improving its biodiversity value. Given that it has been recommended that possum management strategies should include the development of community processes that can assist in the design of appropriate strategies, the leader of the group proposing this plan has organised a meeting at which local stakeholders can express their opinions about the concept of the plan and the control methods used.

    Each of you has been assigned an identity. Be prepared to make a statement based on your identity and defend your point of view. You need to agree on whether the eradication should go ahead, and the methods used to carry out the eradication. Feel free to immerse yourself in your role!

    Roles:

    1. Department of Conservation worker –  Alise
    2. Animal Health Board inspector – Rueben
    3. Dairy farmer whose daughter’s dog died after scavenging a possum that had died from 1080 poisoning – Hannah
    4. Fur trapper – Jenny
    5. Animal rights activist and passionate Greenie – Jamie-Leigh
    6. Urban dweller – Ellyce

    `Optogenetics’: The Stuff of Science Fiction?

    Thursday, July 7th, 2011 | STEPHEN BRONI | No Comments

    When  I was  a wee lad back in Scotland  one of my favourite films  was  a movie called  `Fantastic Voyage’.
    Based on an Issac Asimov novel it’s about a group of scientists who, along with their hi-tech sub are  miniaturised  and injected into the body of an emminent scientist. Their  mission:-  to  perform some very targeted brain surgery from within using lasers.
    (The film is often most remembered by film reviewers for a  scene where our hero has to rip ‘giant’ (to them) `phagocytosing’ white blood cells from a wetsuit-clad Raquel Welsh.  At the time I was way too young to understand why `that scene’ was so appealing to grown-ups!   Especially when there were so many other cool scenes of them travelling  through the blood stream, lungs, inner ear and finally in the brain surrounded by  hanging  neurones!).
    Anyway, when I read this article on `Optogenetics’ -a new technology that  potentially allows scientists to switch  individual neurones on and off by means of light –  the movie leapt into my mind and I  became intrigued to read on.

     It’s  a  facinatating concept  and another example of 21st century ingenuity from   the rapidly expanding world of nanotechnology.

    Check it out here:-

    http://the-scientist.com/2011/07/01/optogenetics-a-light-switch-for-neurons/

    or read full article here

    http://the-scientist.com/2011/07/01/the-birth-of-optogenetics/

    P.S. For all the film buffs out there, a remake of ‘Fantastic Voyage’ in rumoured to be one of James Cameron’s latest projects.

    Arsenic-based life debate continues

    Friday, June 17th, 2011 | STEPHEN BRONI | No Comments

    debate cartoonThere’s no more stimulating way to end a busy week than a good scientific controversy!

    And we are NOT talking Global Warming  this time!

    “More than a dozen researchers voice their  concerns  about a 2010 paper that claims bacteria can use arsenic in place of phosphorus in its DNA and other biomolecules”

    Check out this story in Science from June 2, 2011 and associated links

    http://the-scientist.com/2011/06/02/arsenic-based-life-debate-continues/

    So, which side are you on ????

    The Biology Corner

    Monday, June 13th, 2011 | KEV KNOWLES | No Comments

    The Biology Corner is a resource site for biology and science teachers.  It contains a variety of lessons, quizzes, labs, web quests, and information on science topics.   You can find lessons related to biology topics in the links  listed under “topics” on the sidebar.  Topics include:  Ecology, Genetics, Anatomy, Cells, Scientific Method, and Evolution.
    Great resources here for student revision also!   Really useful revision tools, plus even has a virtual dissection or two!
    http://www.biologycorner.com/

    Protein Synthesis

    Tuesday, May 31st, 2011 | STEPHEN BRONI | No Comments

    DNA fromwwwbuzzlecomA more sedate way to get to grips with Protein synthesis
    than Kev’s recent link to  DNA Rap song on Youtube

    This set of animated slides with View Again and Go-back options allows you to get to grips with  the process at your own pace.

    http://www.wisc-online.com/objects/ap1302/ap1302.swf

    More animated `learning objects’ can be found at www.wisc-online.com

    Evolutionary Evidence from New Zealand

    Thursday, May 26th, 2011 | STEPHEN BRONI | No Comments

    Kakapo,Kea, kaka complexStruggling to get your head around role of polyploidy in speciation, adaptive radiation and such like?
    This page brings those concepts into focus using New Zealand examples.
    http://sci.waikato.ac.nz/evolution/NZevidence.shtml

    Check out the rest of the Evolution for Teaching site for  information on ‘Human Evolution’, `Darwin & Religion’, Earth’s History & Evolution’ and `Theories, Hypotheses, & Laws’.

    A good authoratative site from University of Waikato with a links to glossary &  a useful FAQ page.

    The TalkOrigins Archive: Exploring the Creation/Evolution Controversy

    Monday, May 23rd, 2011 | STEPHEN BRONI | No Comments

     This web site is intended to provide an overview of the study of human evolution, and of the currently accepted fossil evidence. It also contains a very comprehensive treatment of creationist claims about human evolution. If you are not interested in creationism, you can easily skip those pages. If you are interested in creationism, you can go directly to the pages on creationist arguments; they contain links to the fossils under discussion when necessary.

    http://www.talkorigins.org/faqs/homs/

    Human Evolution

    Monday, May 23rd, 2011 | KEV KNOWLES | No Comments

    This achievement standard involves the description of trends in human biological evolution, cultural evolution, and patterns of dispersal.

    Trends refers to progressive change over a period of time in relation to:

    • human biological evolution
    • human cultural evolution
    • patterns of dispersal of hominins. The term hominins refers to living and fossil species belonging to the human lineage. This is a subgroup of hominids which includes both humans and the great apes.

    Trends in human biological evolution begin with early bipedal hominins and may require comparison with living hominids (apes). Trends are limited to:

    • skeletal changes linked to bipedalism
    • changes in skull and endocranial features
    • changes in the manipulative ability of the hand.

    Trends in human cultural evolution will be limited to evidence relating to: use of tools (stone, wood, bone), fire, shelter, clothing, abstract thought (communication, language, art), food-gathering, and domestication of plants and animals.

    • Interpretations on the origins and trends of human evolution will be based on current evidence and may change as a result of recent developments.
    • Evidence relating to human evolution must be scientific evidence which is widely accepted and presented in peer-reviewed scientific journals.

    Speciation

    Monday, May 23rd, 2011 | KEV KNOWLES | No Comments

    This achievement standard involves the description of processes and patterns of evolution.

    Processes of evolution are limited to

    • ways in which speciation occurs (sympatric, allopatric)
    • reproductive isolating mechanisms that contribute to speciation (geographical, temporal, ecological, behavioural, structural barriers, polyploidy)
    • the role of natural selection.

    Patterns of evolution will be selected from: convergent evolution, divergent evolution (including adaptive radiation), co-evolution, punctuated equilibrium, gradualism.

    Plants & Animals

    Monday, May 23rd, 2011 | KEV KNOWLES | No Comments

    This achievement standard involves the description of animal behaviour and plant responses in relation to environmental factors.

    Animal behaviour and plant responses will be selected from those relating to:

    • orientation (tropisms, nastic responses, taxes, kineses, homing, migration)
    • timing (annual, daily, lunar, tidal)
    • interspecific relationships (predation, parasitism, mutualism, commensalism, competition for resources)
    • intraspecific relationships (territoriality, cooperative interactions, reproductive behaviours, hierarchical behaviour, competition for resources).

    The relationship of environmental factors to behaviour/response may be in terms of the process involved or the adaptive significance.

    Genetics

    Saturday, January 1st, 2011 | ouassa | No Comments

    dnaThis achievement standard involves the description of the role DNA has in relation to gene expression and the determination of phenotype.

    The role of DNA includes DNA structure and replication, the control of gene expression, protein synthesis, and the determination of phenotype.

    The structure of DNA includes the molecular components and their role in carrying the genetic code. The replication of DNA includes the processes involved in replication and the role that enzymes have in producing accurate copies.

    Control of gene expression is limited to factors that operate at transcription level:

    • feedback in prokaryotes (repressors, inducers)
    • enhancers and transcription factors in eukaryotes.

    Protein synthesis includes the role of DNA in determining the structure of a protein and how that protein is produced (transcription and translation).

    The determination of phenotype includes:

    • allele interactions: dominance, incomplete dominance, co-dominance, multiple alleles, lethal alleles
    • linkage and sex linkage
    • gene-gene interactions: epistasis, collaboration, polygenes
    • pleiotropy
    • mutations: gene mutations, chromosomal mutations
    • control of metabolic pathways by gene expression.