Darwin’s Theory of Evolution

I. The Puzzle of Life’s Diversity

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

Evolutiontheory

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 factsobservations hypotheses

EVOLUTIONARY THEORY

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

In 1831, at age 22, he joined the crew of

the _______________ as a naturalist fora ________ voyage around the world.

Charles Darwin

H.M.S. Beagle

http://harrier.users.netlink.co.uk/Darwin_sm.jpg

Image from: Biology by Miller and Levine; Prentice Hall Publishing©2006

5 year

During his travels, Darwin wrote thousands

of pages in his journals, drew pictures of

the things he saw, and collected a vast

amount 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?

http://www.rc.umd.edu/praxis/mitchell/images/dinosaur1.gif

differentanimals similar grassland

ecosystems

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.

Biology by Miller and Levine; Prentice Hall Publishing©2006

climates

assortmentunique

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 Islands

Section 15-1

On the desert-like Hood Island,tortoises had long necks…

…while on the lush rainforest of Isabela Island,tortoises had short necks…

on Pinta Island, tortoise neckswere 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

Biology by Miller and Levine; Prentice Hall Publishing©2006

II. Ideas that Shaped Darwin’s Thinking

Image from: Biology by Miller and Levine; Prentice Hall Publishing©2006

• Ideas That Shaped Darwin’s Thinking

A. An Ancient, Changing Earth1. Hutton and Geological Change (1785)2. Lyell’s Principles of Geology (1833)

B. Lamarck’s Evolution Hypotheses (1809)1. Tendency Toward Perfection2. Use and Disuse3. Inheritance of Acquired Traits4. Evaluating Lamarck’s Hypotheses

C. Malthus & Population Growth (1798)

Section 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 shapedgeological 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:

_____________________Thomas Malthus (1798)

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

Ideas that shaped Darwin’s thinking:

_____________________He wrote "Essay on the Principle of

Population" (1798) which inspired Darwin.

The central theme of Malthus' work was that population growth would always overpower food supply growth, creating perpetual states of hunger, disease, and struggle.

Thomas Malthus (1798)

Darwin concluded that this ongoing struggle between those more and less fit to survive would produce a never-ending progression of changes in the organism in simple terms, evolution through natural selection.

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

http://www.educa.rcanaria.es/fundoro/00.corsi.htm

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 aboutgenes and how traits are

_______.

If you lifted weights yourwhole young adult life, andthen you had children, wouldyour kids be more muscular?

inherited

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

http://www.geocities.com/arnold_schwarzenegger_pictures/

What’s right with Lamarck’s hypothesis?

Lamarck was first to develop a scientifichypothesis about _______and recognize that organisms are________________________

evolution

adapted to their environments

http://pegasus.cc.ucf.edu/~he599900/giraffeeating.jpg

a. The earth is really old, and slowly changesb. 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 withthe man or men who proposed it:

a. The earth is really old, and slowly changesb. 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.

Go to Section:

Concept Map

Section 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 recordGeographic

distribution of living species

Homologous body structures

Similaritiesin early

development