Evolution and BiodiversityEvolution and Biodiversity

ConceptsConcepts

Origins Origins

Evolutionary Processes Evolutionary Processes

Ecological Niches Ecological Niches

Species Formation Species Formation

Species Extinction Species Extinction

Origins and Early Evolution of LifeOrigins and Early Evolution of Life

Chemical evolutionChemical evolution

Biological evolutionBiological evolution

Click to view animation. Animation

Stanley Miller's experiment animation.

Plants begininvadingland

Evolution and expansion of life

First fossilrecord ofanimals

Age of reptiles

Age of mammals

Insects and amphibians invade the land

Modern humans(Homo sapiens)appear about2 secondsbefore midnight

Recorded humanhistory begins1/4 secondbefore midnight

Origin of life(3.6–3.8 billionyears ago)

noon

midnight

Evolution ConceptsEvolution Concepts

MicroevolutionMicroevolution

MacroevolutionMacroevolution

Gene poolGene pool

MutationMutation

Natural selectionNatural selection

Natural SelectionNatural Selection

Differential reproductionDifferential reproduction

Adaptive traitAdaptive trait

CoevolutionCoevolution

Natural SelectionNatural Selection

Directional SelectionDirectional Selection

Stabilizing SelectionStabilizing Selection

Disruptive SelectionDisruptive Selection

Click to view animation.

Example of directional selection animation.

Click to view animation.

Stabilizing selection animation.

Click to view animation.

Disruptive selection animation.

Ecological NichesEcological Niches

Ecological niche Ecological niche

Fundamental niche Fundamental niche

Realized niche Realized niche

Broad and Narrow NichesBroad and Narrow Niches

Generalist species r - selected

Generalist species r - selected

Specialist speciesk - selected

Specialist speciesk - selected

Black skimmerseizes small fishat water surface

Flamingofeeds on minuteorganismsin mud

Scaup and otherdiving ducks feed onmollusks, crustaceans,and aquatic vegetation

Brown pelican dives for fish,which it locates from the air

Avocet sweeps bill throughmud and surface water in search of small crustaceans,insects, and seeds

Louisiana heron wades intowater to seize small fish

Oystercatcher feeds onclams, mussels, and other shellfish into which it pries its narrow beak

Dowitcher probes deeplyinto mud in search ofsnails, marine worms,and small crustaceans

Knot (a sandpiper) picks upworms and small crustaceansleft by receding tide

Herring gull is atireless scavenger

Ruddy turnstone searchesunder shells and pebbles for small invertebrates

Piping plover feedson insects and tinycrustaceans on sandy beaches

NichesNiches

Unknown finch ancestor

Insect and nectar eatersFruit and seed eaters

Greater Koa-finch

Kona Grosbeak

Akiapolaau

Maui Parrotbill

Kuai Akialoa

Amakihi

Crested Honeycreeper

Apapane

Adaptive RadiationAdaptive Radiation

SpeciationSpeciation

Speciation Speciation

Geographic isolation Geographic isolation

Reproductive isolation Reproductive isolation

ExtinctionExtinction

Background extinction Background extinction

Mass extinction Mass extinction

Adaptive radiation Adaptive radiation

Mass depletion Mass depletion

Human Impacts Human Impacts

EURASIA

AFRICASO

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IND

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135 million years ago

Present65 million years ago

225 million years ago

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Marineorganisms

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Millions of years ago

Human Impacts on EvolutionHuman Impacts on Evolution

Artificial Selection

Genetic Engineering

Concerns about Genetic Engineering

Artificial Selection

Genetic Engineering

Concerns about Genetic Engineering

Crop

Crossbreeding

Desired trait(color)

ApplePear

Offspring

Crossbreeding

Best results

Newoffspring

Desiredresult

Phase 1Make Modified Gene

Identify and extractgene with desired trait

Identify and removeportion of DNAwith desired trait

Remove plasmidfrom DNA of E. coli

Insert extracted DNA(step 2) into plasmid(step3)

Insert modifiedplasmid into E. coli

Grow in tissueculture tomake copies

cell

gene

DNA

plasmid

E. coliDNA

Geneticallymodifiedplasmid

plasmid

Phase 2Make Transgenic Cell

Transfer plasmidcopies to a carrier

agrobacterium

Agrobacteriuminserts foreignDNA into plantcell to yieldtransgenic cell

Transfer plasmidto surfacemicroscopic metalparticle

Use gene gunto inject DNAinto plant cell

A. tumefaciens(agrobacterium)

Plant cell

Nucleus

Host DNA

Foreign DNA

Phase 3Grow Genetically Engineered Plant

Transgenic cellfrom Phase 2

Cell division oftransgenic cells

Culture cellsto form plantlets

Transgenic plantswith new traits

Transfer to soil

Click to view animation.

Evolutionary tree of life animation.

Click to view animation.

Evolutionary tree diagrams interaction.