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Evolution

Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

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Page 1: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evolution

Page 2: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evidence supporting evolutionFossil record

shows change over timeAnatomical record

comparing body structureshomology & vestigial structuresembryology & development

Molecular recordcomparing protein & DNA sequences

Artificial selectionhuman caused evolution

Page 3: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Fossils help decipher life’s history

LaetoliHyracotherium

Layers of rock contain fossils new layers cover older ones

creates a record over timefossils show evidence for past life

over a long period of time

Page 4: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Fossils tell a story…

the Earth is old

Life is old

Life on Earth has changed

Page 5: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evolution of birdsToday’s organisms descended from ancestral species

Fossil of Archaeopteryxlived about 150 myalinks reptiles & birds

Page 6: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Land Mammal

?

?

?

?

Where are the

intermediate

fossils?Where are the

intermediate

fossils?

Ocean Mammal

Complete seriesof transitional

fossils

Whale evolution

Page 7: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Vestigial organsHind leg bones on whale fossils

Why would whales have pelvis & leg bones if they were always sea creatures?

Dolphin embryo

Hind limb buds

Page 8: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures
Page 9: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evolution from sea to land• 2006 fossil discovery of early tetrapod

o 4 limbs• Missing link from sea to land animals

ichthyostega

Page 10: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Anatomical record

Animals with different structures on the surface

But when you look under the skin…

It tells an evolutionary story of common ancestors

Page 11: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Compare the bones

Homologous Structures

Page 12: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

But don’t be fooled by these…

• Analogous structures• look similar on the outside• Same function• different structure & development

on the inside• different origin• no evolutionary relationship

Solving a similar problem with a similar solution

Page 13: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Analogous structures• Dolphins: aquatic mammal• Fish: aquatic vertebrate

• both adapted to life in the sea

• not closely related

Page 14: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Convergent evolution3 groups with wings

Does this mean they have a recent common ancestor?

Flight evolved 3 separate times — evolving similar solutions to similar “problems”

Page 15: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Convergent evolution led to mimicry

• Why do these pairs look so similar?

Monarch malepoisonous

Viceroy maleedible

Page 16: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Comparative embryology

Development of embryo tells an evolutionary story similar structures during development

Page 17: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Molecular record

100 20 30 40 50 60 70 80 90 100 110 120

LampreyFrogBirdDogMacaqueHuman

328 45 67 125

Comparing DNA & protein structureeveryone uses the same genetic code!

DNA

compare common genescompare common proteins

number of amino acids different from human hemoglobin

Page 18: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Building “family” treesClosely related species are branches on the tree — coming from a common ancestor

Page 19: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evolution: the source of Earth’s biodiversity

• Biological evolution: genetic change in populations of organisms across generations–Natural selection:

reproductive fitness

Page 20: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Understanding evolution is vital• to understand how organisms adapt

to their environment and change over time.

• It is needed for ecology, a central component of environmental science.– Relevant for agricultural,

medicine, pesticide resistance, environmental health

Page 21: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Genetic variation• Genes of better-adapted individuals will be more

prevalent than those of less well-adapted individuals in future generations.

• Adaptive trait (adaptation): a trait (characteristic) that promotes reproductive success

• Mutations: accidental changes in DNA that may be passed on to the next generation– Non-lethal mutations provide the genetic variation on

which natural selection acts.

• Sexual reproduction, which involves recombination (the mixing of parental genes), also leads to variation.

Page 22: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

–functioningfunctioning: beaks in honeycreepers

Evidence of natural selection is everywhere

Page 23: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

• How do we know natural selection can change a population?– we can recreate a similar process– “evolution by human selection”

Artificial selection

“descendants” of wild mustard“descendants” of wild mustard

Page 24: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Artificial selectionHumans create the change over timeHumans create the change over time

“descendants” of the wolf“descendants” of the wolf

Page 25: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Artificial selection

Page 26: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Artificial Selection gone bad!Unexpected consequences of artificial selection

Pesticide resistance

Antibiotic resistance

Page 27: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Insecticide resistance

Spray the field, but…• insecticide didn’t

kill all individuals- variation

• resistant survivors reproduce

• resistance is inherited

• insecticide becomes less & less effective

Page 28: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evolution generates biodiversity

• Biological diversity (biodiversity): an area’s sum total of all organisms –The diversity of species

–Their genes

–Their populations

–Their communities

Page 29: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evolution: A Preview

Adaptation of a population to a new environment – may lead to a new species

Darwin’s Observations

More offspring than needed

Population size is about the same

Individuals differ

Some variation is inherited

Page 30: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evolution: A Preview

Adaptation of a population to a new environment – may lead to a new species

Darwin’s Observations

More offspring than needed

Population size is about the same

Individuals differ

Some variation is inherited

You won’t see this unless you are prepared to see itYou won’t see this unless you are prepared to see it

Page 31: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Expeditions

Alfred Wallace

Brazil Malay Peninsula 8 years 125,000 animal specimens

Access to remote places to make biodiversity collections

Page 32: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Age of the Earth

Uniformitarians

Present mechanisms hold for the past

Erosion & uplifting = mountains

Catastrophists

A few violent events occur suddenly

Page 33: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Age of the Earth

Uniformitarians

Earth must be old

Catastrophists

Earth can be young

Not an evolutionary question

(Bishop Usher: “October 22, 4004 BC” )

Page 34: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Malthus & Population

popu

latio

nsi

ze

time

Tendency to rise beyond numbers that can be supported by the environment

Reduced by disease, war

1776-1834

Page 35: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evolutionary Questions

Do species change?

If so, how?

Evolution: Change through timeEvolution: Change through time

Page 36: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Jean-Baptist Lamarck

Variability within species

Trend of increasing complexity in species

Outstanding Naturalist

Observations

Page 37: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Lamarck’s Theory of Evolution

Species change in response to a changed environment

Species can change by “use”

Changes are passed on

Theory of Acquired Characteristics

Published in 1809

Page 38: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Lamarck’s GiraffeOriginal short necked ancestor

Keeps stretching neck to reach leaves higher up on tree

and stretching

and stretching until neck becomes progressively longer

Page 39: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin’s Giraffe

Original group exhibits variation in neck length

Natural selection favors longer necks: better chance to get higher leaves.

Favored character passed on to next generation

After many, many generations the group is still variable, but shows a general increase in neck length

Page 40: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Lamarck’s Contributions to the Development of Evolutionary Theory

Lamarck’s Contributions to the Development of Evolutionary Theory

• Presented evidence that fossils were the remains of extinct animals.

• Occurrence of fossils suggested to Lamarck that profound changes had taken place during the history of life on earth.

• Proposed the hypothesis of evolution by the inheritance of acquired characteristics.

Page 41: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Lamarck’s Theory of Evolution

Lamarck had good data

It is good common sense

But it isn’t right

Page 42: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Theories in Lamarck’s time

If data support your theory, and

You can’t think of an alternative theory

Your theory must be right

Page 43: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Theories Today

Poor theories are not discarded

A poor theory can only be replaced by a better one

A subtle but important difference

Page 44: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin (1809-1882)

But … Darwin relied on his own observations

Ground work for the acceptance of evolution already done

Many of the main ideas already known

Page 45: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin: Accomplishment

Age 27: 5 year voyage completed

Age 30: good travel book written

Middle age: natural history expert

Age 50: “Origins” published

Lifetime = 20 books, 80 papers

Page 46: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin: Attributes

Gifted experimentalist

Equivalent of a “millionaire”

Quiet & modest lifestyle

Page 47: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin: Attributes

Tremendous energy

Gift of simplicity

Courageous

Wrote so that the common person could read his works

Page 48: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin: Chronology

College, but “sporting set”

Active naturalist, collector

Beagle as companion to Fitzroy

Gone for 5 years

Page 49: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin

South America = no rabbits

But animals therewere similar to rabbits

“Why no rabbits?”

Ancestors had to get there or they must have originated there

Page 50: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

European Rabbit: Oryctolagus cuniculus

Page 51: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Mara:Mara:Dolichotis patagonumDolichotis patagonumMara:Mara:Dolichotis patagonumDolichotis patagonum

Page 52: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin

Struck by similarities between the types of animals(Europe vs. South America)

Found evidence of change in collections of fossils

Page 53: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Returned to EnglandMarried, ill health

Darwin

London

Page 54: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Species in Darwin’s Time

What is a species?

Each species created as a unique entity

Species characteristics do not change

Page 55: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

SpeciesVariability?

Rock Dove

Page 56: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Artificial Selection

I liked breeding pigeons!

Page 57: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin's Ideas

1837: Outline of ideas

1842: Full set of notes

1844: Book length manuscript

But he didn’t publish this ...

Page 58: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Why Did Darwin Wait?

160 pages not enough?

Another book, “Vestiges of the History of Creation”

1856: Nagged by Lyell (geologist)

1857: Wrote to Wallace (to get some facts)

Page 59: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Alfred Russel WallaceAlfred Russel Wallace

1823 - 19131823 - 1913

Page 60: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Wallace

12 pages – same basic conclusion as Darwin12 pages – same basic conclusion as Darwin

1858: Wrote sketch of his theory of evolution

Sent to Darwin to be published

Page 61: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin

Linnean Society Presentation

5 page summary of events

Previous Darwin letter

Wallace’s 12 page letter

Page 62: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Result?

No notice

Darwin produced book by 1859

All copies sold on the first day

10 years later: most scientists believe Darwin’s theory

Page 63: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin’s Natural Selection

A few serious challenges

Ideas languished

Mid-20th century revival

Why so long?Needed a mechanism: modern genetics

Page 64: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin’s Observations & Conclusions

O1: Organisms produce more offspring than are needed for replacement

O2: Population size stays about the same

C1: There is competition for survival

Page 65: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin’s Observations & Conclusions

O3: Natural resources are limited

C2: Most adapted individuals leave more offspring (= natural selection)

Page 66: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin’s Observations & Conclusions

O4: Within a population, individuals exhibit variation in their characteristics

O5: Some variation is inherited (genetic)

Page 67: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin’s Observations & Conclusions

C3: Some organisms exhibit heritable characteristics that make them more likely to survive and produce offspring .

Page 68: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evolution by Natural Selection

Variability in the population

Changed environment

Isolation of the population

Time

Result: adaptation leading to a new species

Genetic ChangeGenetic Change

Page 69: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Evolution Variabilityin the

population

Transport to a different

environment

Isolation & time

Adapted to windAdapted to calm & shade

Page 70: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Genetic Variation in Giraffe Population

Giraffokeryx (extinct- giraffe ancestor 27 mya)

Page 71: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Genetic Variation in Giraffe Population

Page 72: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Giraffes

Page 73: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

The HMS BeagleThe HMS Beagle

Page 74: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Galapagos

Page 75: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Galapagos

Page 76: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures
Page 77: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Galapagos Tortoises

Galapagos Tortoises

Blue footed boobieBlue footed boobie

Page 78: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Sea LionsSea Lions

Page 79: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Marine IguanasMarine Iguanas

Page 80: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Land IguanasLand Iguanas

Page 81: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

MockingbirdsMockingbirds

Long-tailed

Hood

Page 82: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

FinchesFinches

Medium ground finch

Cactus finch

Page 83: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Darwin’s FinchesDarwin’s Finches

Page 84: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures
Page 85: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

DARWIN’S FIVE THEORIES OF EVOLUTION

1. Perpetual Change2. Common Descent3. Multiplication of Species4. Gradualism5. Natural Selection

Page 86: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Perpetual Change

The universe is not constant nor recently created nor perpetually cycling but rather is steadily changing and that organisms are transformed in time.

Page 87: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Horse Evolution

Page 88: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Common Descent

Every group of organisms descended from a common ancestor and all groups of organisms, including animals, plants, and microorganisms, ultimately go back to a single origin of life on earth.

Page 89: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Bears

Page 90: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Carnivores

Page 91: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Amniotes

Page 92: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Multiplication of Species

Species multiply either by splitting into daughter species or by “budding,” that is by establishment of geographically isolated founder populations that evolve into new species.

Page 93: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Foxes

Arctic fox Grey fox

Page 94: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Speciation produces new types of organisms

• Allopatric speciation: species formation due to physical separation of populations– Can be separated by glaciers, rivers,

mountains, etc. – Over time, each population

accumulates different mutations– Populations can no longer interbreed– The main mode of species creation

Page 95: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Model for Allopatric

Speciation

Page 96: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

• Selection of certain traits that enhance reproductive success (fitness)

• Only the organisms best adapted to their environment tend to survive

Natural Selection

Page 97: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Extinction• Extinction: the disappearance of a

species from Earth– Average time a species spends on earth: 1–

10 million years

The number of species in existence = speciation - extinction

Page 98: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

What Contributed to Extinction in Hawaiian Birds and other fauna?

• Hunting

• Disease (mosquitoes)

• Habitat loss

• Invasive species:– Rat, mongoose, ungulates, plants

Page 99: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Some species are more vulnerable to extinction

• Extinction occurs when the environment changes too rapidly for natural selection to work.

• Many factors can cause extinction:– Climate change– Changing sea levels– Arrival of new, harmful species– Severe weather (i.e., droughts)– Specialized species and small populations very

susceptible to extinction– Usually have small populations (i.e., golden toad)

Page 100: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Endemic species: a species only exists in a certain area

Very susceptible to extinctionUsually have small populations (i.e., golden toad)

Okapi

Page 101: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Earth has had several mass extinctions

• Mass extinction events: 5 events in Earth’s history that killed off massive numbers of species at once– 50-95% of all species went extinct at

one time• Humans are causing the sixth mass

extinction event.– Population growth– Development– Resource depletion

Page 102: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Questions

1. A simple definition of "evolution" is:

2. Lamarck's explanation of species changes:

3. An example of a homologous structure is:

4. An example of an analogous structure is:

5. Cabbage, corn, dogs and pigeons are an example of:

Page 103: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures

Questions

6. A theory that is wrong:

7. One of Darwin's notable non-scientific contributions was:

8. Darwin took quite a while to publish his ideas about evolution because:

9. Species evolution by natural selection, according to Darwin, requires that:

Page 104: Evolution. Evidence supporting evolution Fossil record shows change over time Anatomical record comparing body structures homology & vestigial structures