Evidence of EvolutionEvidence of Evolution

15.115.1

Blindfold DemoBlindfold Demo

I. Evolution DefinitionsI. Evolution Definitions

A. A. EvolutionEvolution- Change in - Change in inherited traits of a inherited traits of a POPULATION (not individuals) POPULATION (not individuals) over time.over time.

B. B. VariationVariation- Changes between - Changes between members of the same species members of the same species caused by DNA mutations.caused by DNA mutations.

II. Charles DarwinII. Charles Darwin

A. It all began on the English A. It all began on the English ship, the HMS ship, the HMS BeagleBeagle

1. Darwin worked as the 1. Darwin worked as the naturalistsnaturalists

2. He took samples of living 2. He took samples of living specimens and fossilsspecimens and fossils

II. Charles DarwinII. Charles Darwin

B. Darwin’s observations in B. Darwin’s observations in the Galapagos Islandsthe Galapagos Islands1. Species are unique, yet 1. Species are unique, yet similar to species similar to species elsewhereelsewhere2. Species produce many 2. Species produce many offspring, but don’t overrun offspring, but don’t overrun the earththe earth

II. Charles DarwinII. Charles Darwin

3. Individuals in a species 3. Individuals in a species struggle to survive struggle to survive

a. Compete for fooda. Compete for food

b. Compete for shelterb. Compete for shelter

c. Compete for waterc. Compete for water

d. Etcd. Etc

II. Charles DarwinII. Charles Darwin

C. Pigeon experimentsC. Pigeon experiments

1. Darwin realizes that he 1. Darwin realizes that he can select and breed can select and breed specific pigeons to get a specific pigeons to get a desired trait.desired trait.

II. Charles DarwinII. Charles Darwin

2. 2. Artificial SelectionArtificial Selection- - Breeding organisms with Breeding organisms with specific traits in order to specific traits in order to produce offspring with produce offspring with identical traits.identical traits.

a. Similar to a force in a. Similar to a force in nature nature that causes changesthat causes changes

II. Charles DarwinII. Charles DarwinD. D. Natural SelectionNatural Selection- Organisms - Organisms with favorable traits for their with favorable traits for their environment survive and environment survive and reproduce. Organisms without reproduce. Organisms without favorable traits die!favorable traits die!

1. 1. Survival of the fittest!!!Survival of the fittest!!!

2. Causes changes in populations 2. Causes changes in populations

a. Car demoa. Car demo

II. Charles DarwinII. Charles DarwinE. Principles of Natural SelectionE. Principles of Natural Selection

1. Organisms produce more 1. Organisms produce more offspring than can surviveoffspring than can survive

2. Differences, AKA variations 2. Differences, AKA variations occur among individual speciesoccur among individual species

3. Some variations are passed 3. Some variations are passed to the offspring to the offspring

II. Charles DarwinII. Charles Darwin4. Some variations are helpful 4. Some variations are helpful and help organisms to survive and help organisms to survive and reproduce better.and reproduce better.5. Over time, individuals with 5. Over time, individuals with the helpful variations make up the helpful variations make up more of the population and more of the population and often becomes a separate often becomes a separate species.species.

RUEBEN VS. CARS DEMORUEBEN VS. CARS DEMO

III. Evidence for EvolutionIII. Evidence for Evolution

A. Adaptations that A. Adaptations that increase survivalincrease survival 1. Structural1. Structural

a. a. Body partsb. Camouflageb. Camouflagec. Mimicryc. Mimicry

III. Evidence for EvolutionIII. Evidence for Evolution

2. Physiological- 2. Physiological- Changes in Changes in

metabolismmetabolism

a. Penicillin a. Penicillin resistant bacteriaresistant bacteria

b. Pesticide b. Pesticide resistant insectsresistant insects

III. EVIDENCE FOR EVOLUTIONIII. EVIDENCE FOR EVOLUTION

B. Fossils & Transition Fossils B. Fossils & Transition Fossils 1. 1. ArcheopteryxArcheopteryx: intermediate : intermediate between reptiles & birdsbetween reptiles & birds2. 2. EustheopteronEustheopteron: fish to : fish to amphibiansamphibians3. 3. SeymouriaSeymouria: amphibian to : amphibian to reptilesreptiles4. 4. TherapsidsTherapsids: reptiles to : reptiles to mammalsmammals

III. EVIDENCE FOR EVOLUTIONIII. EVIDENCE FOR EVOLUTION

C. Anatomical EvidenceC. Anatomical Evidence1. 1. Homologous StructuresHomologous Structures- - Structure with similar origins Structure with similar origins (shape, function, etc)(shape, function, etc)

a. Provides evidence of a. Provides evidence of common ancestorcommon ancestor

b. Ex: Forelimbs of whales, b. Ex: Forelimbs of whales, crocodiles and birdscrocodiles and birds

Anatomical EvidenceAnatomical EvidenceHomologous StructuresHomologous Structures

III. EVIDENCE FOR EVOLUTIONIII. EVIDENCE FOR EVOLUTION

2. 2. Analogous StructuresAnalogous Structures- - Structures that DO NOT Structures that DO NOT have similar origin, but DO have similar origin, but DO have similar functionshave similar functions

a. Not closely relateda. Not closely relatedb. Wing of a butterfly b. Wing of a butterfly

and and wing of a birdwing of a bird

Anatomical EvidenceAnatomical Evidenceanalogous structuresanalogous structures

III. EVIDENCE FOR EVOLUTIONIII. EVIDENCE FOR EVOLUTION

3. 3. Vestigial StructuresVestigial Structures- - Structures that no longer Structures that no longer serve their original purposeserve their original purpose

1. Ex: Human ear 1. Ex: Human ear muscles, muscles, whale feet, whale feet, blind mole-rat blind mole-rat eyeseyes

Anatomical EvidenceAnatomical Evidencevestigial structuresvestigial structures

III. EVIDENCE FOR EVOLUTIONIII. EVIDENCE FOR EVOLUTION

4. Embryology Evidence4. Embryology Evidence

a. a. EmbryoEmbryo- Earliest stage - Earliest stage of of growth & developmentgrowth & development

b. All embryos look b. All embryos look similarsimilar

Evidence from EmbryologyEvidence from Embryology

•http://www.exploratorium.edu/exhibits/embryo/embryo.html

III. EVIDENCE FOR EVOLUTIONIII. EVIDENCE FOR EVOLUTION

5. Biochemistry 5. Biochemistry EvidenceEvidence

a. DNA is a. DNA is similar similar in all in all speciesspecies

b. Evidence b. Evidence of of common common ancestorancestor

III. EVIDENCE FOR EVOLUTIONIII. EVIDENCE FOR EVOLUTION

c. The more DNA alleles c. The more DNA alleles in in common, the more common, the more closely closely related two related two organisms are!organisms are!

1) Humans & chimps 1) Humans & chimps have have 97% of the same 97% of the same DNADNA