studied medicine at Edinburgh University (1825-1827) where the

sight of blood and surgery without

anesthetics repulsed him

studied medicine at Edinburgh University (1825-1827) where the

sight of blood and surgery without

anesthetics repulsed him

studied to become a clergyman at Cambridge University (1827-1831)

studied to become a clergyman at Cambridge University (1827-1831)

born in Shrewsbury, England, in 1809

born in Shrewsbury, England, in 1809

After Cambridge, Charles was recommended for a surveying trip on the HMS Beagle.

After Cambridge, Charles was recommended for a surveying trip on the HMS Beagle.

Darwin sailed around the world on the Beagle for 5 years, working as a naturalist.

Darwin sailed around the world on the Beagle for 5 years, working as a naturalist.

Darwin made many observations and

collected evidence on his voyage that led to his theory

about the way life changes.

Darwin made many observations and

collected evidence on his voyage that led to his theory

about the way life changes.

At the time Darwin made his trip, the majority of

people believed the Earth and all of its forms of life had been created only a few thousand years in

the past.

At the time Darwin made his trip, the majority of

people believed the Earth and all of its forms of life had been created only a few thousand years in

the past.

People also believed in fixity of species; in other words, species never changed.

People also believed in fixity of species; in other words, species never changed.

After careful observation and

study of new scientific

discoveries, Darwin began to think otherwise.

After careful observation and

study of new scientific

discoveries, Darwin began to think otherwise.

People also believed that the Earth had not changed during those few thousand years.People also believed that the Earth had not changed during those few thousand years.

The first dinosaur to be described scientifically was Megalosaurus by William Buckland in 1824.

Darwin was influenced by geologist James

Hutton’s writings that described geologic

forces he thought had changed and were still

changing the earth.

Darwin was influenced by geologist James

Hutton’s writings that described geologic

forces he thought had changed and were still

changing the earth.

Hutton proposed that the Earth had to be

much more than a few thousand years old.

Hutton proposed that the Earth had to be

much more than a few thousand years old.

The Father of GeologyThe Father of Geology

Darwin was also influenced by

geologist Charles Lyell who wrote

Principia Geologica.

Darwin was also influenced by

geologist Charles Lyell who wrote

Principia Geologica.

Lyell’s book proposed that tremendous

geologic processes had shaped the Earth

such as seen in volcanoes active in

the present.

Lyell’s book proposed that tremendous

geologic processes had shaped the Earth

such as seen in volcanoes active in

the present.

On the voyage, Darwin noticed

that everywhere he went, the animals

and plants differed vastly.

On the voyage, Darwin noticed

that everywhere he went, the animals

and plants differed vastly.

Patterns in the species suggested that the

species had changed over time and had given rise to new and different

species.

Patterns in the species suggested that the

species had changed over time and had given rise to new and different

species.

The Galapagos Islands lie 500 miles west of Ecuador in the Pacific Ocean,

directly on the equator.

The Galapagos Islands lie 500 miles west of Ecuador in the Pacific Ocean,

directly on the equator.

Many of Darwin’s conclusions were

based on observations of

wildlife in the Galapagos Islands.

Many of Darwin’s conclusions were

based on observations of

wildlife in the Galapagos Islands.

“Galapagos” means turtle.

What it must have been like to be Darwin…

Darwin noticed on these islands,

there were several types of finches.

Darwin noticed on these islands,

there were several types of finches.

In particular, Darwin observed something odd

about the finches: they all

looked like a bird he had seen

on the South American continent.

In particular, Darwin observed something odd

about the finches: they all

looked like a bird he had seen

on the South American continent.

Darwin wondered if the birds and other animals had been created to match their

environment, why didn’t these birds look like the birds of the African continent, since the

environments of both the Galapagos and Africa were similar.

Darwin wondered if the birds and other animals had been created to match their

environment, why didn’t these birds look like the birds of the African continent, since the

environments of both the Galapagos and Africa were similar.

Darwin guessed that some of the birds

from South America migrated to the

Galapagos.

Darwin guessed that some of the birds

from South America migrated to the

Galapagos.

Once on the islands, the birds must have

changed over the years.

Once on the islands, the birds must have

changed over the years.

This would explain the numerous species of birds present.

This would explain the numerous species of birds present.

woodpecker finch

cactus finch

large ground finch

Darwin called this…Darwin called this…

oror

(change in species over time)(change in species over time)

Darwin concluded:

Each species has descended, with changes, from other species over time.

Darwin concluded:

Each species has descended, with changes, from other species over time.

Descent With ModificationsDescent With Modifications

Malthus was a British social scientist who

proposed theories on factors controlling population growth:

Malthus was a British social scientist who

proposed theories on factors controlling population growth:

People have more children than are able to survive.People have more children than are able to survive.

There are built-in population checks: disease, famine, and war.There are built-in population checks: disease, famine, and war.

Darwin based his theory on his own observations

and the writings of Thomas Malthus.

Darwin based his theory on his own observations

and the writings of Thomas Malthus.

Darwin extended these principles to biology, which

helped him form his theory of…

Darwin extended these principles to biology, which

helped him form his theory of…

…or Survival of the Fittest.…or Survival of the Fittest.

Natural selection was the mechanism by which Darwin proposed that evolution took place.

Natural selection was the mechanism by which Darwin proposed that evolution took place.

Darwin published his theory in the bookDarwin published his theory in the book

Five basic components ofFive basic components of

1. All species have genetic variation.1. All species have genetic variation.

Every species is different, even within itself.Every species is different, even within itself.

Look around you…are you all the same?Look around you…are you all the same?

2. Organisms produce more offspring than can survive. Many that survive do not produce offspring.

2. Organisms produce more offspring than can survive. Many that survive do not produce offspring.

The female green sea turtle lays a clutch of about 110 eggs. She may lay several clutches.The female green sea turtle lays a clutch of about 110 eggs. She may lay several clutches.

It is likely that less than 1% of the hatchlings will ever reach sexual maturity.

It is likely that less than 1% of the hatchlings will ever reach sexual maturity.

3. Since more organisms are produced than can survive, there is competition (struggle for existence).

3. Since more organisms are produced than can survive, there is competition (struggle for existence).

Competition exists WITHIN and AMONG species.Competition exists WITHIN and AMONG species.

foodfood

Within and Among Species for

And Within a Species for

waterwater

matesmates

sheltershelter spacespace

The constant struggle for survival is affected by short-term natural disasters. (drought, fires, floods, snowstorms, hurricanes, and tornadoes)

The constant struggle for survival is affected by short-term natural disasters. (drought, fires, floods, snowstorms, hurricanes, and tornadoes)

The constant struggle for survival is also affected by long-term changes in the environment. (ice ages, biome shifts, etc)

The constant struggle for survival is also affected by long-term changes in the environment. (ice ages, biome shifts, etc)

4. Survival of the fittest Some organisms are more suited to their environment as a result of variations in the species.

4. Survival of the fittest Some organisms are more suited to their environment as a result of variations in the species.

Fitness: the ability of an individual to survive and reproduce in its specific environment. Fitness is a result of adaptations.

Fitness: the ability of an individual to survive and reproduce in its specific environment. Fitness is a result of adaptations.

He who spreads the most genes wins!He who spreads the most genes wins!1st1st

Individuals that are fit to their environment survive and leave more offspring than those who aren’t.

Individuals that are fit to their environment survive and leave more offspring than those who aren’t.

5. Descent with modification: Living species today are descended with modifications from common ancestral species that lived in the past.

5. Descent with modification: Living species today are descended with modifications from common ancestral species that lived in the past.

Over time, genes for less favored characteristics will be eliminated from the gene pool.

Over time, genes for less favored characteristics will be eliminated from the gene pool.

Example: giraffes and their increasingly longer necks.

Example: giraffes and their increasingly longer necks.

Characteristics of fit individuals increase in a population over time.Characteristics of fit individuals increase in a population over time.

Natural Selection: Survival of the FittestNatural Selection: Survival of the Fittest

the variation exists first.the variation exists first.

An adaptation is any inherited characteristic (a genetic variation) that can increase an organism’s chance of survival.

An adaptation is any inherited characteristic (a genetic variation) that can increase an organism’s chance of survival.

the environment changes.the environment changes.

a variation may give an advantage to survive environmental change.

a variation may give an advantage to survive environmental change.

An organism does not change because of need or desire to survive. The organism either already has the variation that enables it to survive or it dies.

An organism does not change because of need or desire to survive. The organism either already has the variation that enables it to survive or it dies.

As the environment changes, organisms must have variations that allow them to survive (adapt) to those changes or die

As the environment changes, organisms must have variations that allow them to survive (adapt) to those changes or die

If an entire population of a species cannot adapt, that species becomes extinct.

If an entire population of a species cannot adapt, that species becomes extinct.

There have been at least 5 MASS extinctions during Earth’s history where a huge % of the living species were destroyed

There have been at least 5 MASS extinctions during Earth’s history where a huge % of the living species were destroyed

At least one of these has been

attributed to meteor impact and it’s consequences.

At least one of these has been

attributed to meteor impact and it’s consequences.

It is estimated that 1/5 or more of the world’s species will become extinct if the rainforests are destroyed.

It is estimated that 1/5 or more of the world’s species will become extinct if the rainforests are destroyed.

Many scientists say that the

earth is currently

experiencing a mass extinction

crisis.

Many scientists say that the

earth is currently

experiencing a mass extinction

crisis.

If we are in a period of mass extinction . . . What animals will your grandchildren be able to see in the wild?

If we are in a period of mass extinction . . . What animals will your grandchildren be able to see in the wild?

Visit the World Wildlife Fund website for more information

on endangered species.

Photos by MartinHarveyWorld WildlifeFund International

Davis, Donald E. “Meteor Impact”. (Also public domain from NASA.) No date. Online image with permission. Dinosaurs and Their Extinction. June 10, 2004. <http://www.donaldedavis.com/PARTS/DDDINOS.html>

Davis, Donald E. “Meteor Impact”. (Also public domain from NASA.) No date. Online image with permission. Dinosaurs and Their Extinction. June 10, 2004. <http://www.donaldedavis.com/PARTS/DDDINOS.html>

“Snow Alaska”. No date. Online image. Public Domain. Mineral Management Service. June 10, 2004. GeekPhilospher.com <http://geekphilosopher.com/bkg/snowAlaskaIce.htm>

“Snow Alaska”. No date. Online image. Public Domain. Mineral Management Service. June 10, 2004. GeekPhilospher.com <http://geekphilosopher.com/bkg/snowAlaskaIce.htm>

“Clearcut in Cameroon Rainforest”. No date. Online image. June 11, 2004. Earth Crash Earth Spirit. <http://www.eces.org/archive/gallery/forestsgfx/forests39.shtml>

“Clearcut in Cameroon Rainforest”. No date. Online image. June 11, 2004. Earth Crash Earth Spirit. <http://www.eces.org/archive/gallery/forestsgfx/forests39.shtml>

Harvey, Martin. No date. Online image. World Wildlife Fund. June 11, 2004. <http://www.panda.org>Harvey, Martin. No date. Online image. World Wildlife Fund. June 11, 2004. <http://www.panda.org>

“Allosaur”. No date. Online image. Public Domain. Dinosaur National Monument. National Park Service. June 10, 2004. http://www.nps.gov/dino/index.htm

“Allosaur”. No date. Online image. Public Domain. Dinosaur National Monument. National Park Service. June 10, 2004. http://www.nps.gov/dino/index.htm