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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

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!

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:

“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.

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)

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

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

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/

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

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/

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

 

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?

    • `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.

    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.

    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.