1. Down with Creationism In the early 18 th century the commonly held belief of Creationism was being questioned Extinctions such as the dodo led them to produce alternative theories

2. Lamark Lamark proposed that aquired characteristics were in inherited He used the example of the giraffe stretching its neck This is now know to be wrong but it was the first attempt to explain how species change over time

3. Darwin’s Tree of Life

4. ‘‘I think’’ This is alleged to be Charles Darwin's first sketch of an evolutionary tree of life (circa 1837), taken from his First Notebook on Transmutation of Species Darwin hypothesised that all living things descended from our Last Universal Common Ancestor

5. The Tree of Life From LUCA the different species branch out The biological ‘holy grail’ was to build up an image of this tree in its entirety

6. It started off so well… Early RNA sequencing compared RNA in various organisms Some species were not as closely related as was previously thought Tree highly biased to species that are alive today

7. Hybrids and HGT Darwin’s model does not take into account HYBRIDIZATION or HORIZONTAL GENE TRANSFER –The 'Tree of Life' starts to resemble a 'Web of Life

8. Web of life This tangled mass is more representative as it illustrates that species can exchange genetic information with each other A ‘web of life’ is a more accurate way to depict the way species are interrelated "If there is a tree of life it's a small irregular structure growing out of the web of life." Dr John Dupré

9. ‘‘The tree of life was useful’’ The concept of the Tree of Life gave rise to the theory of evolution It is time to adapt Darwin’s original theory as modern scientific techniques have changed "The tree of life was useful. It helped us to understand evolution was real. But now we know more about evolution it's time to move on.’’ Dr Eric Bapteste

10. References Darwin’s notebook: www.fossilmuseum.net/Evolution/darwin/darwintreewww.fossilmuseum.net/Evolution/darwin/darwintree Lamark’s giraffes: www.princessleia.com/images/essays/giraffe_lamark.jpg Darwin image: www.darwin-online.org.uk Lawton, G; 2009; ‘Uprooting Darwin’s Tree’; New Scientist; 24 th January; page 34 LUCA tree: www.nature.com/nature/journalwww.nature.com/nature/journal www.telegraph.co.uk/scienceandtechnology www.physorg.com/news www.biologymad.com www.biomedcentral.com/ Open University ‘Tree of Life’ Web of Life: http://sandwalk.blogspot.com/2009/01/darwin-was-wrong Mule image: http://www.ruralmissouri.org/04pages/04SeptKahoka.html Ligre image: http://news.nationalgeographic.com/news/2005/08/photogalleries/ligers_dynamite