Development of Evolutionary theory

1) Charles Darwin

2) Alfred Russel Wallace

Darwin's Ideas

1) While on a voyage (For 5 Years) around the world studying plants and animals, he noticed that there was variation of members of the same species and that those with characteristics most suited to the environment were more likely to survive. He also noticed that characteristics could be passed on to offspring.

Wallace's Ideas

1) Wallaces observations provides lots of evidence to help support the theory of evolution by natural selection. E.g. he had realised that warning colours are used by some species (e.g. butterflies) to deter predators from eating them - an example of a beneficial characteristic that had evolved by natural selection.

1) Helps us understand that all life changes are through the proccess of evolution, and that evidence suggests we have all decended from a common ancestor.

It Has Effected areas of Biology Such As:

1) Classification - if all living organisms have decended from a common ancestor we're all related in some way. Now they group things in to how closely related they are.

2) Antibiotic Resistance - Now we understand the importance of finishing the course of drugs to prevent resistant bacteria spreading and we know we need to constantly develop new antibiotics to fight newly evolved bacteria.

3) Conservation - We now understand the importance of genetic diversity and how it helps populations  adapt to changing environments. This has lead to conservation projects to help protect species.

1) A pentadactyl limb is a limb with five digits.

2) You can see the pentadactyl limb in many species e.g. mammal, Anphibian etc.

3) In each of the species the pentadactyl limb has a similar bone structure, but usually have different functions. E.g Bats wings and a human hand are pentadactyl limbs.                                              

4) The similarity is bone structure provides evidence that species with a pentadactyllimb have all evolved from a common ancestor.