Natural Selection

Fast lion vs. slow zebra Strong, healthy person vs. weak, sick person

Turn and talk: Who has the greatest
chance of survival?

Turn and talk:What does this phrase mean?

Who was Charles Darwin?

■ Charles Darwin

■ Set sail on the HMS Beagle in 1831

■ Became the ship’s naturalist

■ Arrived in the Galapagos Islands in 1835

■ Observed that the animals on the islands

were similar to those on the mainland

Darwin’s Theory of Natural Selection

1.There is variation within any species

2. All organisms tend to over-reproduce
making competition for food and
water.

3.There is a struggle for survival which
can lead to extinction.

4.The fittest survive and pass on their
genes which may lead to new
species.

5.The environment determines who is
the fittest.

What did he say?

1. Variation: Variation exists within all

populations. Much of it is inherited because it is created by crossing over during meiosis.

What did he say?

2. Overpopulation:
Every population is
capable of producing
more offspring than
can survive. There
are limited
resources.

What did he say?

3. Struggle for Existence: Members of
each species for food, living space, etc.

What did he say?

4. Selection:The organisms with the
best traits/adaptations will survive
and have the opportunity to pass on
it’s traits to offspring.

5. Environmental
Adaptations:

Organisms that
are better
adapted to their
environment
have a higher
chance of
survival.

Katydids have camouflage to
look like leaves.

Non-poisonous king snakes mimic
poisonous coral snakes.

Evolution Recap

Multiple Choice

This makes an organism more suited to its environment

• species

• lifespan

• adaptation

• mutation

Multiple Choice

Where the better adapted organisms survive to pass traits along to offspring.

• Evolution

• Natural Selection

• Extinction

• Artifical Selection

Multiple Choice

Which organisms are most likely to survive?

• the best adapted

• the fastest

• the strongest

• the most domesticated (tamed)

Multiple Choice

Why is the mouse population changing over time?

• The light mice can reproduce more successfully than the dark mice

• The hawks eat more dark mice than light mice because the dark mice taste better

• The hawks eat more light mice than dark mice because they can see the light mice more easily

• The hawks eat more dark mice than light mice because they can see the dark mice more easily

Multiple Choice

These moths are all the same species. The differences between their wings is an example of ________________

• Natural Selection

• Variation

• Homeostasis

• Extinction

Multiple Choice

Which of the following is the correct definition of natural selection?

• The idea that organisms less equipped for their environment tend to survive longer

• The idea that organisms more well equipped for their environment tend to survive longer

• The idea that organisms more well equipped for their environment tend to not survive

• None.

Multiple Choice

Which of the following represents genetic drift?

Multiple Choice

Which of the following represents migration?

Multiple Choice

Which of the following represents gene flow?

Match

Match the following

• the movement of genes into or out of a population

• Random chance; small population

• A sudden change in one or more characteristics due to a change in a gene

• Occurs due to physical difference as a result of a genetic difference

• The movement of organisms from one place to another

Gene Flow

Genetic Drift

Mutation

Non-Random Mating

Migration

• Gene Flow

• Genetic Drift

• Mutation

• Non-Random Mating

• Migration

Multiple Choice

Which of the following best describes what the image represents?

• Genetic Drift

• Migration

• Mutation

• Natural Selection

Multiple Choice

Which of the following best describes what the image represents?

• Natural Selection

• Artificial Selection

• Mutation

• Genetic Drift

Multiple Choice

Which of the following does not show genetic drift?

Multiple Choice

Which scientist is considered the father of evolution?

• Jean-Baptist Lamarck

• Hershey and Chase

• Charles Darwin

• Carleous Linnaeus

Multiple Choice

Which of the following is an example of artificial selection?

• Gorillas are in the wild and have a baby gorilla.

• A group of ants in an ant pile are exterminated by an exterminator.

• A black speckled rabbit is a new favorite among children, a white and black rabbit are picked to make black and white baby bunnies.

• Wolves in the wild have pups.

Multiple Choice

White tigers are becoming extinct, to overcome this a male and female white tiger are paired together in captivity to help their population continue to grow. This is an example of:

• Natural Selection

• Gene Flow

• Artificial Selection

• Genetic Drift

Multiple Choice

Blue catfish are going extinct. A dam in a lake full of blue catfish bursts due to poor engineering and kills some of the blue catfish. This is an example of:

• Natural Selection

• Gene Flow

• Mutation

• Genetic Drift

Multiple Choice

Green rhinocerous beetles are some of the biggest beetles to exist on Earth. A green rhinocerous beetle leaves its group and wonders over to another group that only has red rhinocerous beetles and mates with the red beetles. This is an example of:

• Gene Flow

• Genetic Drift

• Mutation

• Migration

Natural Selection: How Does it Work?

By Stefan Mejia-Ott

Evolution results from a process called natural selection.

Natural Selection!

Natural selection is a process in which organisms better suited to their environment are able to survive and reproduce more offspring

These favorable traits and characteristics are then passed on to their babies through a process called inheritance.

Multiple Choice

Evolution is the result of a process called ____________

• Natural Selection

• Artificial Selection

• Survival of the Weakest

• Supernatural Selection

Multiple Choice

According to natural selection, organisms more suited to their environment are better able to

• Sleep

• Survive

• Perish

• Migrate

Multiple Choice

The process of passing down favorable traits to one's offspring is called

• Artificial Selection

• Mutations

• Evolution

• Inheritance

The process of natural selection happens when an individual’s genes become different in some way from the genes of others of its kind.

Differences in genes cause differences in an individual’s traits—such as how it looks or its behavior.

Multiple Choice

Natural selection happens when an individual's genes ______________ from the genes of other members of its species.

• Become different

• Stay the same

• Become separated

Multiple Choice

Differences in genes can cause differences in __________ (Choose the best answer).

• Mutations

• RNA

• Appearance

Changes in genetic material are called mutations.

Mutations can occur at any time during an organism’s life span.

Mutations can be inherited or happen randomly. They can also be caused by environmental factors such as too much sunlight.

Multiple Choice

Changes in genetic material are called _____________

• Mutations

• RNA

• Genes

Multiple Choice

Mutations can be inherited or be

• Chosen by the individual organism

• Caused by environmental factors

• Refused at any time

Most changes in genes either harm the individual or do not matter much.

But some changes help an individual to survive and reproduce.

For example, an animal may have better vision or faster legs. These traits may help it find food and avoid its enemies.

Multiple Choice

True or False? All changes in genes are harmless.

• True

• False

Multiple Choice

Some changes in genes can help organisms _____

• Survive

• Mutate

• Rest