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.