BLUE CARD!!!! 1. Choose a species of animals that

Darwin observed and EXPLAIN the adaptation.

2. I.D. and EXPLAIN someone or something that influenced Darwin in his beliefs.

NOTE: Did I mention EXPLAIN……

Evolution Darwin’s Theory of Evolution

Australopithecus 3.5 MYA

Neanderthal Man 80-50 TYA

Charles Darwin English Born 1809 HMS Beagle - 1831 Naturalist Very Religious

Darwin’s Observations Animals and plants were well

adapted Diverse reproductive strategies Puzzled by location of animals

Rabbits in Argentina, not in Australia Fossils

similar, dissimilar, Extinction

The Beagle’s Journey

Pinta IslandIntermediate shell

Pinta

Isabela IslandDome-shaped shell

Hood IslandSaddle-backed shellHoodFloreana

Santa Fe

Santa Cruz

James

Marchena

Fernandina

Isabela

Tower

Giant Tortoises of the Galápagos IslandsSection 15-1

The Galapagos Islands

DesertLarge rainfall

Intermediate Shell

Domed Shell

Saddle backed Shell

Climate variation throughout

Tortoises of the Galapagos

Saddleback long neck,

curved shell, found on Hood Island, desert like

Dome Shaped shorter neck,

domed shell, lush vegetation, covers the ground, Isabela island

Many different varieties in different locations

Finches

Journey Home Animals and plants varied a great

deal from island to island

Did the organisms on different islands belong to the same species?

Was the ancestor from S. America?

Influences on Darwin Fossil Record

James Hutton - 1785 Earth - millions of years old, not

5700

Charles Lyell - 1833 Past events are explained by the

processes that scientists can see today. Made observations of Niagara Falls

Jean-Baptiste Lamarck - 1809 Proposes 1st theory of evolution

use vs. disuse acquired traits are passed on leads to changes in species

 Lamarck’s Theory of Evolution

Thomas Malthus - 1798 Economist - unchecked population

growth leads to a lack of space and food

Frog Eggs - What detemines survival?

Artificial Selection

Farmers and breeders Selective Breeding

On his return Marries Emma Wedgwood (1st

cousin) Has 10 children, 3 die before

adulthood, many have medical issues (why do you think?) 3 sons are knighted.

1836-1859 Family Illness Atolls Barnacles Charles Lyell

1858 1858 - On Charles

Lyell’s advice begins writing up his views for a book to be called Natural Selection.

1858 (June) Receives letter

from Alfred Wallace

He is collecting specimens in Indonesia.

Shared with Lyell

Darwin’s View - On the Origin of the Species - 1859

The Origin of Species Natural Selection Survival of the Fittest Struggle for Existence Descent with Modifications

Darwin’s Evidence of Evolution

Fossil Record Distribution of Living Species Homologous Body Structures Embryo Development

Fossil Record Information of past life, including

structure of organisms and the order in which they lived

Fossils Provide Insight to the Past

Natural Variation passed on to future

generations

Struggle for Existence

                                                                                                                                                                                                                                                                                                 

                                                                                                                                                                                             

Survival of the Fittest - (Natural Selection)

Individuals that are best suited for their environment have high levels of fitness and therefore survive and reproduce

Adaptations - physical characteristics or

behaviors

Camouflage

Descent with Modification

Species change overtime All organisms share a common

ancestor (common descent)

Reviewing Darwin’s Theory

Variation Large amounts of offspring Competition Struggle for Existence Survival of the Fittest Descent with Modification via

Natural Selection Common Decent

How does evolution really work?

Distribution of Living Species - I

Unrelated organisms look similar because of common ecological conditions - Convergent Evolution

Beaver

NORTH AMERICA

Muskrat

Capybara SOUTH AMERICA

Coypu

Geographic Distribution of Living Species

Beaver

Muskrat

Beaver andMuskrat

Coypu

Capybara

Coypu andCapybara

Distribution of Living Species - II

Finches - all share a common mainland ancestor, differences are due to the environment

Homologous Structures - same basic design,

modifications

Analogous StructuresSimilar Function/Looks different

Wing of insect, bird, bat, and pterosaur

Vestigial Organs - traces of homologous

structures

Embryo DevelopmentEmbryonic Cells develop in the same group and similar patterns

BiochemistryEx. Blood proteins, DNA,

etc.

Patterns of Evolution

Divergent Evolution Adaptive Radiation

Process by which a single species or group evolves into several different forms that live in different ways

Darwin’s finches Hawaiian

honeycreepers

Convergent Evolution Unrelated species become more and

more similar in appearance as they adapt to the same environment Desert plants

Coevolution Two species evolve due to their

interactions Predators and their prey

Examples? Plants and pollinators

Examples?

Speciation Influences

Gene pool Geographic isolation Physical separation of members of a

population

Genetic Equilibrium Results in NO EVOLUTION A population in which allele

frequencies do not change from generation to generation

1. No mutations occur2. No migration occurs3. There is a large population4. Individuals mate randomly5. Natural selection does NOT

occur

Disruption of Genetic Equilibrium

1. Mutations Physical change in a gene or

chromosome “Variations” Produce new alleles for a trait

Disruption of Genetic Equilibrium

2. Migration Movement of individual organisms into

or out of a population Immigration vs. Emigration

Disruption of Genetic Equilibrium

3. Genetic Drift A shift in the allele frequencies in a

population due to random events or chance

Disruption of Genetic Equilibrium

4. Extinction Species die off Members trait did not allow them to

survive and pass genes on to the next generation

The population didn’t have proper adaptations to survive and reproduce

Species is lost forever

Darwin’s notebooks