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Evolution in Action. Chapter 15, section 3. Caribbean Anole Lizards. Anolis insolitus Way of life: Inhabits tree branches Adaptations: Thin body, short legs, large toe pads. Anolis pulchellus Way of life: Stays in grass Adaptations: Slender, very long tails. Anolis cybotes
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Evolution in Action Chapter 15, section 3
Caribbean Anole Lizards Anolis insolitus Way of life: Inhabits tree branches Adaptations: Thin body, short legs, large toe pads Anolis pulchellus Way of life: Stays in grass Adaptations: Slender, very long tails Anolis cybotes Way of life: Dwells on tree trucks and ground Adaptations: Long, strong legs for speed, stocky bodies
Caribbean Anole Lizards • Distinct species of anole with the same body type occur on different islands • Ex. A distinct species of twig dwelling anole is found on each island • Scientists have compared DNA from all the species • Found that each specialized body type evolved independently on each island
Convergent Evolution • The process by which unrelated species evolve similar traits • Each Twig dwelling species evolved from different ancestors but evolved similar adaptations to similar environments
Divergent Evolution • The process by which the descendants of a single ancestor diversify into species that fit different parts of the environment • Smaller lizards may have been chased away by larger lizards, they could climb higher and hold on to branches more efficiently Thousands of years of selection of more slender anoles with large forepaws and short legs produced a new species
Adaptive radiation • A new population in a new environment will undergo divergent evolution until the population fills many parts of the environment • Most common in islands
Artificial Selection • When a human breeder chooses individuals that will parent the next generation • This process is called artificial selection because people (instead of nature) select which organisms get to reproduce Farmers have cultivated numerous popular crops from the wild mustard, by artificially selecting for certain attributes.
Coevolution • When two or more species have evolved adaptations to each other’s influence • Often seen in a number of species of flowering plants that coevolved with specific pollinators • Moth-pollinated plants often have spurs or tubes the exact length of a certain moth’s “tongue.” • Charles Darwin predicted the existence of a moth in Madagascar based on the size and shape of a flower he saw there. • Discovered about 40 years later.