Evidence of Evolution Darwin Argued That Living Things

Evidence of Evolution Darwin Argued That Living Things Have Been Evolving On Earth For Millions of Years. Evidence For This Process Could Be Found In: l The Fossil Record l The Geographical Distribution of Living Species l Homologous Structures of Living Organisms l Similarities In Early Development l Similarities in Amino Acid Sequence 1

Fossil Record l Earth is Billions of Years Old l Fossils In Different Layers of Rock (sedimentary Rock Strata) Showed Evidence Of Gradual Change Over Time 2

Fossilized Trilobite Fossilized Dinosaur Heart

Geographic Distribution of Living Species l Different Animals On Different Continents But Similar Adaptations To Shared Environments 5

Homologous Body Structures l Structures That Have Different Mature Forms But Develop From The Same Embryonic Tissues l Strong Evidence That All Four-Limbed Animals With Backbones Descended, With Modification, From A Common Ancestor 6

Homologous Body Structures l May Differ In Form or Function l Limb Bones Develop In Similar Patterns l. Arms, Wings, Legs, Flippers 7

Homologous Structures 8

Homologous Body Structures 9

Homologous Body Structures l Not l All Serve Important Functions Vestigial Organs- structures that do not seem to have a function Appendix and Tailbone In Man l Legs On Skinks l Hip bones in Whales l Hip/Legs in snakes l 10

Similarities In Early Development l Embryonic Structures Of Different Species Show Significant Similarities l Embryo – early stages of vertebrate development l Implies that genetically, we have not "forgotten" our evolutionary history, only built upon it. 12

Human Fetus – 5 weeks 13

Chicken Turtle Rat 15

Evidence for Evolution - Comparative Embryology Similarities In Embryonic Development 16

Similarities in DNA Sequence 17

Similarities in DNA Sequence • Chimpanzee & Human DNA are 99% identical • Bird & human DNA are only 60% identical • Plant and Human DNA are only 10% identical

Evolution of pesticide resistance in response to selection 19

Evidence for Evolution – Evolution Observed Evolution of drug-resistance in HIV 20