Emergence of Evolutionary ThoughtEmergence of Evolutionary ThoughtEvolution:Evolution: __________________ in populations of __________________ in populations of organisms over timeorganisms over timeEarly Explanation of life’s diversityEarly Explanation of life’s diversitySpecies individually created ________________ and Species individually created ________________ and ____________________________________Questions arising from such thoughtsQuestions arising from such thoughtsWhy were organisms ________________ in different Why were organisms ________________ in different regions of earth?regions of earth?Why are ____________organisms different from Why are ____________organisms different from ________________ organisms?________________ organisms?If each species is different, why are there the same If each species is different, why are there the same ________________________________ (bone plans) ________________________________ (bone plans) that do different things in animals?that do different things in animals?New IdeasNew IdeasScientists thought that species _________ over timeScientists thought that species _________ over time

Both animals, though very different, Both animals, though very different, exhibit similar wing structuresexhibit similar wing structures

Extinction, fossil record, and Carbon-14 dating Extinction, fossil record, and Carbon-14 dating suggest that organisms arose (and became suggest that organisms arose (and became

extinct) at different time periods extinct) at different time periods

Chimps- Arose on earth ~6 million years ago

Dinosaurs- Arise ~ 200 mya- Dinosaurs- Arise ~ 200 mya-

Extinct 65 myaExtinct 65 mya

Woolly Mammoth- Extinct Woolly Mammoth- Extinct 4500 years ago4500 years ago

Different regions of planet have animals Different regions of planet have animals with unique traits that help them survivewith unique traits that help them survive

New IdeasNew IdeasScientists thought that species ___________Scientists thought that species ___________

over timeover time

Lamarck’s Disproven Theory of EvolutionLamarck’s Disproven Theory of Evolution

Jean Baptiste LamarckJean Baptiste Lamarck

Believed that an animal’s ____________Believed that an animal’s ____________

_____ determine its development and genes_____ determine its development and genes

Exp. GiraffeExp. Giraffe

Early Giraffes stretched their necks to feedEarly Giraffes stretched their necks to feed

Long neck was then _________ to offspringLong neck was then _________ to offspring

________________________________________

Charles Darwin 1809-1882Charles Darwin 1809-1882

Putting the Picture TogetherPutting the Picture Together

Darwin Travels to the Galapagos IslandsDarwin Travels to the Galapagos Islands

Witnessed ______________________ of animal lifeWitnessed ______________________ of animal life

Fascinated by differences among _______________Fascinated by differences among _______________

Becomes convinced that species _______________Becomes convinced that species _______________

Young bull Old bull

Thomas Malthus & Charles DarwinThomas Malthus & Charles Darwin

Malthus Malthus

Populations tend to ______________ than Populations tend to ______________ than the food supply needed to feed itthe food supply needed to feed it

Charles Lyell & Charles DarwinCharles Lyell & Charles Darwin

LyellLyell

Changes occur over time in geology; land Changes occur over time in geology; land ____________________________________________________________________________

Darwn’s Descent with ModificationDarwn’s Descent with ModificationEvolutionary pathway resembled a _____________Evolutionary pathway resembled a _____________

_______ a ladder from lower forms to higher forms_______ a ladder from lower forms to higher forms

No species that exists today was an ____________ No species that exists today was an ____________ to another living speciesto another living species

Darwin’s ObservationsDarwin’s Observations

•_____________ in a population ___________, some _____________ in a population ___________, some of these variations are inheritableof these variations are inheritable

•Populations produce __________________ than Populations produce __________________ than the environment’s food, space, and other assets.the environment’s food, space, and other assets.

•Therefore, species _______________for resourcesTherefore, species _______________for resources

Lions and cheetahs compete for foodLions and cheetahs compete for food

Dolphins compete for baitfishDolphins compete for baitfish

The Mechanism of Natural SelectionThe Mechanism of Natural Selection

Natural Selection Natural Selection ___________________________ displayed ___________________________ displayed by individuals with _____________ traitsby individuals with _____________ traits

Nature _____________ traits that are passed on to the next Nature _____________ traits that are passed on to the next generationgeneration

VariationVariation _________________ within a population _________________ within a population

AdaptationsAdaptations traits that are selected for because they help traits that are selected for because they help an __________________________________an __________________________________

Evolution occurs when _________ in a population change Evolution occurs when _________ in a population change shift to enhance ___________________________shift to enhance ___________________________

Exp. GiraffeExp. Giraffe

How Do Variations Arise?How Do Variations Arise?•Natural selection __________ the cause of variationNatural selection __________ the cause of variation

•Mutation-> Random ______________ in DNA Mutation-> Random ______________ in DNA sequences in the parents genomesequences in the parents genome

•Gene ShufflingGene Shuffling ________ of parental ________ of parental chromosomes can create ____ genetic combinationschromosomes can create ____ genetic combinations

•Variation arises _________________. Variations are Variation arises _________________. Variations are then selected on by nature. then selected on by nature.

•Variations which are selected for are called Variations which are selected for are called __________________________________________

Adaptations and SpeciationAdaptations and SpeciationTypes of Adaptations Types of Adaptations •Structural AdaptationsStructural Adaptations Involve ___________ or Involve ___________ or __________________________________

Bird’s beak, Anteaters _____________________Bird’s beak, Anteaters _____________________•Physiological AdaptationsPhysiological Adaptations ___________________ ___________________ in organismsin organisms

Poison ___________in a snake, _____ of an octopusPoison ___________in a snake, _____ of an octopus•Behavioral AdaptationsBehavioral Adaptations _______________ aids in _______________ aids in survival and reproductionsurvival and reproduction

Wildabeasts/ Caribou/ Bird ___________________Wildabeasts/ Caribou/ Bird ___________________

Wolves ______________ in Packs Wolves ______________ in Packs

Fish swim in ___________________Fish swim in ___________________

Types of AdaptationsTypes of Adaptations

StructuralStructural

PhysiologicalPhysiological

Wolf PackWolf Pack

Herd of African GazellesHerd of African Gazelles

Species & SpeciationSpecies & SpeciationSpecies Species group of organisms that can group of organisms that can __________________and produce ________offspring__________________and produce ________offspring

Horses + Donkey = ________…Not the same species Horses + Donkey = ________…Not the same species

Human male + human female = _______________ Human male + human female = _______________ baby…same species!baby…same species!

HorseHorse DonkeyDonkey MuleMule

Speciation Speciation Organisms which are separated by Organisms which are separated by distance + gene pool will ______________ distance + gene pool will ______________ interbreed. Each group becomes ________________interbreed. Each group becomes ________________

Types of Natural SelectionTypes of Natural Selection

Directional Selection Directional Selection shifts a population toward shifts a population toward ____________________ form of a trait____________________ form of a trait

Example: 4 million years ago; heavy cheetahsExample: 4 million years ago; heavy cheetahs

Over time, _______________________ animals Over time, _______________________ animals reproduced more successfullyreproduced more successfully

Natural selection favored the genes that pushed the Natural selection favored the genes that pushed the cheetah’s weight in ___________________________cheetah’s weight in ___________________________

Types of Natural SelectionTypes of Natural SelectionStabilizing SelectionStabilizing Selection shifts a population toward shifts a population toward ________________________ traits________________________ traits

Example: Most human babies weight ~ ___________Example: Most human babies weight ~ ___________

Disruptive Selection Disruptive Selection ______________ phenotypes ______________ phenotypes are more commonare more common

Example: African butterflies appear as either bright Example: African butterflies appear as either bright __________________________________________________________

These colors mimic other butterflies that are ______These colors mimic other butterflies that are ______

____________________; less likely to be eaten____________________; less likely to be eaten

Intermediate butterflies look like __________, and Intermediate butterflies look like __________, and are _____________________ to be eatenare _____________________ to be eaten

Patterns of EvolutionPatterns of Evolution

Species become ____________________ over timeSpecies become ____________________ over time

Gradual Change Gradual Change Genetic changes occur Genetic changes occur _____________over ______________ generations_____________over ______________ generations

Divergent Evolution Divergent Evolution Single population is split Single population is split into ________________ populations.into ________________ populations.

Exp. Ground squirrels in the Grand Canyon were Exp. Ground squirrels in the Grand Canyon were split into _________________ after canyon widenedsplit into _________________ after canyon widened

Patterns of EvolutionPatterns of EvolutionAdaptive Radiation Adaptive Radiation Organisms occupy Organisms occupy ________________niches in an environment and ________________niches in an environment and _______________________from one another_______________________from one another

Exp. Darwin’s FinchesExp. Darwin’s Finches

Convergent Evolution Convergent Evolution ________________ species ________________ species evolve in ways to make them _________more similarevolve in ways to make them _________more similar

Exp. Sugar GlidersExp. Sugar Gliders winged marsupials in ________ winged marsupials in ________

Flying Squirrels Flying Squirrels Winged squirrels in ___________ Winged squirrels in ___________

__________________________________________________________

Sugar GliderSugar Glider Flying SquirrelFlying Squirrel

Populations & Evolution• Larger populations tend to have ______ genetic variation• Smaller populations tend to have ________ genetic variation• Genetic Drift/Founder Effect _____________________due

small population sizes. _______________ more likely• 10,000 years ago, _____________________go extinct due to

climate changes. Resulting cheetahs have little genetic diversity

Pace of EvolutionPace of EvolutionGradualism Gradualism Over time, new species arise as Over time, new species arise as environment changeenvironment change

If true, we should see ____________________ in If true, we should see ____________________ in fossil record…not always truefossil record…not always true

Punctuated Equilibrium Punctuated Equilibrium Species exist for long Species exist for long periods of time without changes, then periods of time without changes, then ________________ occur over short periods of time________________ occur over short periods of time

Evidence for EvolutionEvidence for EvolutionFossil Fossil ______________ that is preserved in rock ______________ that is preserved in rock

Found in _________________________Found in _________________________

Fossils show overall ___________________ of how Fossils show overall ___________________ of how living things evolvedliving things evolved

Body ___________Body ___________

Feeding __________Feeding __________

MobilityMobility

Society?Society?

_____________ fossils in upper layers, __________ _____________ fossils in upper layers, __________ fossils in lower layersfossils in lower layers

ExamplesExamplesBurgess ShaleBurgess Shale

Location : ___________________________________Location : ___________________________________

Development: Foot of _________________________Development: Foot of _________________________

Organisms: Early Marine worms ________________Organisms: Early Marine worms ________________

Badlands, SDBadlands, SD

Development: ______________________Development: ______________________

Organisms: _________________________Organisms: _________________________

BadlandsBadlands

ImportanceImportance

Land _____________________Land _____________________

Were once covered _________________________Were once covered _________________________

Species ________________________Species ________________________

Comparative AnatomyComparative Anatomy

Homologous structuresHomologous structures ____________________ in ____________________ in related organismsrelated organisms

Suggests that organisms ______________________ Suggests that organisms ______________________ ancestorancestor

Exp. Cheetah forelimb = _______________________Exp. Cheetah forelimb = _______________________

Wing = ________________________Wing = ________________________

Vestigial OrgansVestigial Organs

Organs with no apparent use, but resemble Organs with no apparent use, but resemble ______________________ in ancestors______________________ in ancestors

Whale ____________Whale ____________

Whale ____________Whale ____________

Wisdom __________Wisdom __________

____________________________________

Comparative EmbryologyComparative Embryology

Organisms with common descent have Organisms with common descent have __________________________________Vertebrates breathe _____________________Vertebrates breathe _____________________

As embryos, ________________________ (turns into As embryos, ________________________ (turns into Eustachian tube)Eustachian tube)

BiochemistryBiochemistry

Common ancestors have similar fundamental body Common ancestors have similar fundamental body chemistrychemistry

Most organisms have:Most organisms have:

Same ______________________Same ______________________

Same ______________________Same ______________________

BiogeographyBiogeography

Study of species distribution on Galapagos Islands Study of species distribution on Galapagos Islands ____________________________________ species____________________________________ species

Each island would have to had it own special Each island would have to had it own special creation event for each species; more likely creation event for each species; more likely ________________________________________________________________________________________

Direct EvidenceDirect Evidence

Bacteria & _____________________Bacteria & _____________________

Fruit Flies (Drosophila)Fruit Flies (Drosophila)

Artificial SelectionArtificial selection (or selective breeding) describes intentional breeding for certain traits, or combination of traits

Dogs are a prime example.

Bulldogs selectively bred for increasingly large heads. Most bulldogs delivered via Caesarian Section. Trait not favored in nature, but selected for by humans