the puzzle of life’s diversity chapter 15-1 2 3.pdfdarwin’s theory of evolution the puzzle of...

Darwin’s Theory of EvolutionThe Puzzle of Life’s Diversity

Chapter 15-1

WRITE A DEFINITION:

EVOLUTION:

THEORY:

FOSSIL:

change over time; the process by which modern

organisms have descended from ancient organisms

a well-supported testable explanation of

phenomena that have occurred in the natural world

the preserved remains of ancient organisms

evolution

fossiltheory

The _______ that Darwin found caused him to ask questions that led to his proposal of the theory of_________._______ provide evidence to support the theory of_________.

________ is a______; a testable explanation of naturally-occurring phenomena

The _____ record provides for some of the evidence that supports the ______ of evolution

Evolution

theory

fossils

evolutionFossils

evolution

fossil

theory

The total variety of all the organisms in the biosphere

= ________________

Where did all these different organisms come from?

How are they related?

BIODIVERSITY

REMEMBER !

What scientific explanation can account for the diversity of life?

ANSWER:

A collection of ______________,

__________, and ___________ known as

________________________

Scientific facts

observations hypotheses

EVOLUTIONARY THEORY

The person who contributed themost to our understanding of evolution was ______________________

In 1831, at age 22, he joined the crew ofthe _______________ as a naturalist fora ________ voyage around the world.

Charles Darwin

H.M.S. Beagle5 year

During his travels, Darwin wrote thousandsof pages in his journals, drew pictures ofthe things he saw, and collected a vastamount of ______________ that led himto propose a _______________________about the way _____________.

revolutionary hypothesisevidence

life changes

DARWIN WONDERED?

Why do Argentina and Australia have ______________ even though they have ______________________?

Why are there no ______ in Australia andno ________ in England?

Why have so many species disappeared?

How are these ______ species _______ to living species?

different

animals similar grasslandecosystems

rabbitskangaroos

extinctrelated

Who Was Charles Darwin?

While on his voyage around the world aboard the ____________, Charles Darwin spent about one month observing life on the

________________.

There, he encountered some unique animals, such as ______ and ________.

Galápagos Islands

H.M.S. Beagle

finches tortoises

The Galάpagos Islands are close together but have very different _______.

Some were hot and dry, with little vegetation.

Others had more rainfall and were rich in vegetation

Each island hadits own _____ _________ of plant and animal species.

climates

assortment

unique

Pinta IslandIntermediate shell

Pinta

Isabela IslandDome-shaped shell

Hood IslandSaddle-backed shell

HoodFloreana

Santa Fe

Santa Cruz

James

Marchena

Fernandina

Isabela

Tower

Giant Tortoises of the Galápagos

IslandsSection 15-1

On the desert-like Hood Island,

tortoises had long necks…

while on the lush rainforest of Isabela Island, tortoises had

short necks…

and on Pinta Island, tortoise necks were somewhere in

between

After his voyage, Darwin spent a great deal of time thinking about his findings.

He began to wonder if animals living ondifferent islands had once been membersof the ____________ that haddeveloped _________ characteristicsafter becoming _______ from oneanother in different habitats.

same speciesdifferent

isolated

Darwin’s Theory of EvolutionIdeas that Shaped Darwin’s Thinking

Chapter 15-2

Ideas that shaped Darwin’s thinking:

In 1785 ______________proposes that the ______________ by_________________occurring over__________ periods of time, and is_______________ old.

very long

James Hutton

Earth was shaped

geological forces

millions of years

Ideas that shaped Darwin’s thinking:

In 1833 ___________ explains that the geological processes still ___________ have shaped Earth’s features over ________________

Charles Lyell

occurring now

long periods of time

Ideas that shaped Darwin’s thinking:

Theory of Pangaea

…and continentaldrift

Living things must compete for food, shelter, space, mates

competition

REMEMBER !Chapter 3

Ideas that shaped Darwin’s thinking:

_____________________

He observed that babies were being born

faster than people were dying. He

reasoned that if the human population

continued to grow, sooner or later there

would be _______________________

Thomas Malthus (1798)

insufficient space & food

Ideas that shaped Darwin’s thinking:

___________________________was one of first scientists to recognize living things_______________ and thatall species were ________ fromother species.

Lamarck published his hypothesis of________________________ the year Darwin was born.

changed over time

Jean-Baptiste Lamarck (1809)

descended

Inheritance of Acquired traits

The male fiddler crab uses itsfront claw to attract mates andward off predators.

Through repeated use, the frontclaw becomes larger.

The fiddler passes on this acquired characteristic to its offspring

What’s wrong with Lamarck’s hypothesis?

Lamarck didn’t know about

genes and how traits are _______.

If you lifted weights your

whole young adult life, and

then you had children, would

your kids be more muscular?

inherited

NO! Acquired traits may help an organism, but they won’t be passed on to offspring.

What’s right with Lamarck’s hypothesis?

Lamarck was first to

develop a scientific

hypothesis about

_______

and recognize that

organisms are

________________________

evolution

adapted to their environments

a. The earth is really old, and slowly changes

b. Living things pass changes on to their offspring, leading to species changesc. Sooner or later growing populations run out of resourcesd. Living things change slowly over time because of competition for resources,

and pass those changes on to their offspring

Hutton

Lyell

Malthus

Lamarck

Match the letter of the idea with

the man or men who proposed it:

a. The earth is really old, and slowly changes

b. Living things pass changes on to their offspring, leading to species changesc. Sooner or later growing populations run out of resourcesd. Living things change slowly over time because of competition for resources,

and pass those changes on to their offspring

Hutton

Lyell

Malthus

Lamarck

a.

c.

b.

d.

Concept MapSection 15-3

includes

Evidence of Evolution

Physical remains of

organisms

Common ancestral

species

Similar genes Similar genes

which is composed of which indicates which implies which implies

The fossil record

Geographic

distribution of

living species

Homologous

body structures

Similarities

in early

development

Darwin’s Theory of EvolutionDarwin Presents his Case

Chapter 15-3

What do oranges, broccoli, and Butterball turkeys have to do with

EVOLUTION?(Answers to come in this slide show!)

THINK ABOUT IT

After Darwin returned to England in 1836he filled notebooks with his ideasabout _____________ and the processthat he would later call _______.

He did not rush to publish his ideasbecause they ________ with thefundamental scientific ______ of hisday.

He asked his wife to publishhis ideas when he ___.

evolutionspecies diversity

died

disagreedbeliefs

In 1858 another naturalist,

_________________, wrote an

essay describing his work in _______ that

summarized the same ideas _____ had

been thinking about for 25 years!

Alfred Russel Wallace

Malaysia

Darwin

Suddenly Darwin had incentive to publish

the results of his work!

In 1859

____________________

presented _______

and proposed a

________ for evolution

that he called

__________________

On the Origin of Species

evidence

mechanism

NATURAL SELECTION

WHAT IS DARWIN’S THEORY?

_________________ is found

naturally in all populations

GENETIC VARIATION

WHAT IS DARWIN’S THEORY?

______________________

means that members of each species

must ________ for food, space, and

other __________.

STRUGGLE FOR EXISTANCE

COMPETE

RESOURCES

WHAT IS DARWIN’S THEORY?

Some organisms in a ________

are ________ to survive.

population

less likely

WHAT IS DARWIN’S THEORY?_____________________organisms which are better adapted to the environment will ______ and________, passing on their _____.

SURVIVAL OF THE FITTEST

survivereproduce genes

Ability of an individual to ______

____________ in its specific

environment

= ______fitness

surviveand reproduce

Any ___________________ that

increases an organism’s ______________

= _____________ADAPTATION

inherited characteristic

chance of survival

Over time, natural selectionresults in ________ in theinherited characteristics of a __________.

These changes ______ aspecies’ _____ in its environment.

WHAT IS DARWIN’S THEORY?

CHANGES

POPULATION

increase

fitness

____________________________suggests that each species has ___________, with ________,from other species over time.

This idea suggests that all living species are ____________________, and that all species, living and extinct,share a _________________.

WHAT IS DARWIN’S THEORY?

DESCENT WITH MODIFICATION

DESCENDED CHANGES

RELATED TO EACH OTHER

COMMON ANCESTOR

EVIDENCE OF EVOLUTION:

1.________________

2.________________

3. _______________

4. _______________

5. _______________

6. _______________

7. _______________

Fossil recordGeographic Distribution

Homologous structures

EmbryologyDNA

See Natural selection happen

Artificial selection

• ARTIFICIAL SELECTION WORKSIn artificial selection, ____________

provides the _________ through

_________ and _________________

and ______________ those traits that they

find ______.

NATUREvariation

mutation sexual reproduction

humans select

useful EX: We have selected for and bred cows to produce more milk,turkeys with more breast meat, etc.

Breeds of Dogs

Chihuahua – bred from Techichi of Mexico

by Mayans, had religious significance

Saint Bernard – bred by monks around 1050 A.D.to rescue travelers of mountain passes in the

Swiss Alps between Italy and Switzerland

Irish Wolfhound – bred in Ireland to hunt wolves and elk

Dachshund – bred in Germany as earlyas the 15th century to hunt badgers

ARTIFICIAL SELECTION WORKS

How Do We Know Evolution Happens?

2. The Fossil Record –

______ are the _______

_________________

found in layers of rock

in the Earth.

Fossils

of ancient organisms

remains

How Do We Know Evolution Happens?

The layers of rock tell the history of the

_____, while the _____ found within

the rock tell a history of ___.

The fossils are thought

to be the ________ as

the rock they

are found in.

Earth fossilslife

same age

Sea level

Sedimentary rocks form in horizontal

layers.

When part of Earth’s crust is compressed, a

bend in a rock forms, tilting the

rock layers.

As the surface erodes due to water, wind, waves,

or glaciers, the older rock surface

is exposed.

Movement of Earth’s Crust

Fish die inthe ocean

and arecovered insediment.

Over timeand under

increasingpressure,the remains

becomesfossilized

Earthquakes and volcanoes

cause uplifting of the layers of theEarth, taking the fossils along

Fossils ofmarinefish found

on themountain-

sides ofsouthwest

Wyoming,which atone time

was covered

by aninland sea

TRANSITIONAL FOSSILS HAVE BEEN FOUND

If Darwin’s theory is correct you would expect to find ____________ yet _______________ living in a _________ region as they spread into nearby habitats and evolve.

different speciesclosely related

geographic

That’s EXACTLY what we do see!

REMEMBER THE GALAPAGOS TORTOISES?

Little vegetationLong necks

Lots of vegetationShort necks

Intermediate vegetationIntermediate necks

Tortoises adapted to different habitats as they spread from the mainland to the different islands.= DIVERGENT EVOLUTION = ADAPTIVE RADIATION

GALAPAGOS FINCHES

The _____ of Galapagos finches have ______ to eating a _____ of _____.

beaksadapted variety foods

If Darwin’s theory is correct you would also expect to find _______________ living in ________ geographic regionsbut similar habitats becoming ________ as they adapt to ______________.

far apartdifferent species

more alike

That’s EXACTLY what we do see!

similar ecosystems

Whales and sharks have a _____ body designeven though they are very _______ organisms (one is a fish; the other, a mammal)because they have _________________ to living in a _____ environment.

= CONVERGENT EVOLUTION

similardifferent

independently adaptedsimilar

Whales are closely related to wolves, but don’t look or act much like them = divergent evolution

Whales are distantly related to sharks, but look and act morelike them =convergent evolution

Conclusion:The pressure ofthe environmentdrives evolution

4. _____________________HOMOLOGOUS Structures

4. Homologous Body Structures –

Structures, like the limbs of

vertebrates, look very _______,

but are made from the

__________, because

they are made from

the same clump of

_____________ cells

in the _______.

same bones

embryo

undifferentiated

different

Turtle Alligator Bird Mammal

Ancient lobe-finned fish

Figure 15–15 Homologous Body StructuresSection 15-3

4. Homologous Body Structures –

Some _______________________

are _______ and have no useful

function even though they are still

present, like ________in whales and

boa constrictors.

homologous body structures

vestigial

hipbones

Most mammals have a pouch between their small and large intestine that contains bacteria to digest plants called a _____.

In humans the cecumis shrunken and unused.

It is our _________appendix

cecum

Why grow a tail and then lose it?

HUMAN EMBRYO_________________

__________________________________Tail disappears at

has a tail at 4 weeks

about 8 weekstail

Skinks are a type of lizard. In some species, legs have become so small they _______

______ in walking.Why would an organism possess organs ___________________?

One explanation:The ________ is present to make the organ, but_________________ through ______________.If the organ is not vital to survival, then natural selection would not cause its elimination.

no longer

function

gene codechange over timefunction has been lost

little or no functionwith

5. _____________________

________ of many animals with back-

bones are very similar.

Similarities in Embryology

Embryos

It is clear that the same groups of

_____________ cells develop in the

same order to produce the same

tissues and organs of all vertebrates,

suggesting that they all _______ from

a _______________.

undifferentiated

evolved

common ancestor

6. _______________

Similarities in ____ and ________ sequencessuggestrelatedness

Similarities in DNA

PROTEINDNA

Similar _________ suggest an ___________________.

Human- 46 chromosomes Chimpanzee- 48 chromosomes

karyotypesevolutionary relationship

1. ________________________

If you take the two smaller chromosomes apes have that we don’t, and place them end to end, the ______ _______________ to the #2 human chromosome __________________.

BANDING PATTERN MATCHES

bandingpattern is identical

wehave that they don’t

2. ____________________Chromosomes have special sequences called _______ at their ends to protect the strands during replication.

TELOMERES IN MIDDLE

telomeres

2. TELOMERES IN MIDDLE

Telomere sequences are found __________ and _____________________ of human chromosome #2 suggesting it was made by _____ two other chromosomes together.

→

→

→

ALSO IN THE MIDDLEat the ends

fusing

3. _________________

Chromosome #2 has a second _______________________ region

→

EXTRA CENTROMERE

CENTROMEREINACTIVE

Did you ever wonder why dogs and

cats don’t need to eat ________, but

_______? YOU DO

fresh fruit

Fish, amphibians, reptiles, and most

mammals can make their own

_________, but humans need to eat

fresh fruit or they end up with

________.

VITAMIN C

SCURVY

Human DNA contains the gene that

codes for the enzyme to make

vitamin C, but it is ________________.

Guess what other group of organisms

lack the ability to make their own

Vitamin C?

NONFUNCTIONAL

PRIMATES…

which includes

chimpanzees, orangutans,

gorillas, and other apes.

Humans have many other

nonfunctional vestigial genes called

________________.

EX: Humans have more than 99

different odor receptor genes, but more

than 70% of them are ___________.

PSEUDOGENES

nonfunctional

WHY DOES EVOLUTION MATTER NOW?

There is a natural

variation in populations

of peppered moths.

________________

___________________

7.____________________________

EX: Peppered Moths

Can see Natural selection happen

Typica form - lighter

Carbonaria form - darker

Typica

Carbonaria

The ___________ form was the predominant form

in England _____________________________.

Around the middle of the 19th century the ______ form began to appear. It was first reported in 1848. By 1895 98% of the moths in Manchester

were the ____ variety.

In recent years, the burning of cleaner fuels and Clean Air

regulations has reduced the pollution there and the ______ colored moths have increased in numbers.

light coloredprior to the Industrial Revolution

darker

dark

lighter

7.____________________________

EX: Changes in disease-causing microbes that produce new organisms and __________.

_______

___

__________________________

Can see Natural selection happen

Bird flu

Antibiotic-resistant tuberculosis

HIV

new diseases