BIO-1202 Lecture 3: Biology II, jan 25
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{ charles darwin continued : evidence galapagos finches, finches on galapagos all resemble mainland finches in some form (11 species, all have adaptations for their environments. * marine iguanas on galapagos, longer nails than land ones. Also have glands to release excess salt from water. Can dive 30 ft. only for under 10 minutes. Adapted to each island, based off food sources. Traits are selected against: passed on to next generation, populations evolve by natural selection. Traits change over time, then become stable in a population. Wallace"s li(cid:374)e tre(cid:374)ch, a(cid:374)i(cid:373)als do(cid:374)"t cross it so it shows the variation on different sides. Bacteria are able to adapt and develop resistance to it over time. Fossil- any evidence of an organism from more than 10,000 years ago. Fossils record is often incomplete: features mark transitions from one group to another. 250,000 species in fossils record: many millions of species, odds are against fossils forming.