Adaptationand

Evidence for evolution

What’s the adaptation?

• Changes over time in response to the environment that increase a species chance of survival.

• Adaptations develop in a species over time

Structural• Thorns• Claws • Teeth• Camouflage• Mimicry

Other Evidence of Evolution

1. Fossil record

2. Comparative Anatomy

3. Comparative Embryology

4. Biochemistry

1. The Fossil Record– Older, simpler fossils precede more complex,

younger fossils– Fossils show progression

Evolution of Modern Horse in Fossil Record

2. AnatomyA. Vestigial structures- no more function.

• Pelvis in whales, snakes• Appendix in humans

• B. Homologous structures. Structural similarity of body features. Humors, radius, ulna in forelimbs of vertebrates

3. Embryology. Similar developmental stages of animal embryos

4. Biochemistry- Molecular evidence of evolution. Comparison of DNA or AA sequence between different species

– Chimpanzee & Human DNA are 99% identical– Bird & human DNA are only 60% identical– Plant and Human DNA are only 10% identical