Evidence For Evolution

Evidence for evolution: Anatomy Topic Evidence Importance Anatomy Vestigial Structures - Structures that have no or little use Closely related species have fully functional versions of vestigial structures

Evidence for evolution: Anatomy Topic Evidence Importance Anatomy Homologous structures Similar anatomy suggests relationship

Evidence for evolution: Fossils Topic Evidence Importance Fossils Extinct organisms Life has not remained consistent over time

Evidence for evolution: Fossils Topic Evidence Importance Fossils Transitional fossils A fossil that shows traits of both ancestor and descendents

Archaeopteryx

Microraptor Discovered by Xu Xing in 2000

Evidence for evolution: Fossils Topic Evidence Importance Genetics Similar DNA sequence Two organisms with similar DNA sequences are probably closely related

Human DNA is 98.8% similar to chimpanzee

But only 93.4% similar to baboons Unlike humans and chimps, baboons have tails

Mechanism for evolution Natural Selection Darwin’s idea Mechanism for evolution

Individuals vary in traits 4 Principles Individuals vary in traits Not everyone can survive (struggle for existance)

Differences in traits can affect your ability to survive 4 Principles Cont. Differences in traits can affect your ability to survive Differences can be passed from parent to offspring (Heredity)

Traits Vary Peppered moths come in black and white (variation)

Not Everyone Survives Birds eat moths (struggle for existence)

Differences Affect Survival Black moths are harder to see on black bark, and thus more survive

Differences Are Passed From Parent to Offspring Because more black moths survive, they produce more black offspring B BB b Bb

Summary Black moths survive better, thus produce more offspring Future generations will have more black moths Eventually the white moth may go extinct