Evolution at work
Examples of Darwin-style "natural selection" in natural and human environments
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| Comparison of Darwin's finches from the Galapagos. Only finches were found on the islands, apparently descended from a single common ancestor. Over time, the finches evolved into new species taking the role of other birds on the mainland | Galapagos tortoises. Giant tortoises take the place of grazing animals (e.g. deer) on the islands. Tortoises from different islands have different shell and neck types, adapted for local vegetation |
| Selective breeding (artificial evolution) | |
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| Wolf (ancestral to dogs) in Montana | Husky (little modification from wolf) |
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| Irish wolfhound (ancient breed) | Doberman (recent breed, large, highly modified) |
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| Bulldog (muzzle crushed in to make face more human, muscular for fighting and "ratting") | Chihuahua (tiny, massively mutated dog) |
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| Boston Terrier (crushed muzzle, tiny size) | |
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| Wolf skull | Pekingese skull (more apelike/human) |
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| African wildcat (probable ancestor of domestic cat) | Bengal (domestic breed with little modification) |
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| Siamese (highly mutated cat) | Hairless cat (another major highly mutated cat) |
| MISSING LINKS - image credits: Nature April 6, 2006 | |
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| Tiktaalik - a transitional animal between fish and amphibians - detail of skeleton | |
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| Ichthyostega - a very early amphibian - detail of skeleton | |
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| Diagram of changes in fish fins as they evolved to become legs in tetrapods | |
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| Diagram showing transition of fish to early amphibians | |
| SEXUAL SELECTION | |
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| Male deer, showing antlers which grow solely for the rutting season - attractive to females, used in non-lethal contests | Moose, a deer with very large antlers |
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| Irish Elk - extinct deer with gigantic antlers used in sexual displays | |
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