Forces of Evolution

Review

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

• Selective pressure: An environmental factor that causes certain traits to be more or less advantageous, leading to changes in the frequency of those traits

• Fitness: An organism's ability to survive and reproduce; species that are more 'fit' will reproduce and pass on their genes more often

As you proceed:

Record the definitions/descriptions of the following terms in your "Evolution Vocab" note sheet.

• Mutation

• Gene flow

• Genetic drift

• Founder effect

• Bottleneck effect

Multiple Choice

Which rabbit has the selective advantage?

Multiple Choice

Which rabbit has the selective advantage?

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

True or False? All changes in genes are harmless.

• True

• False

Multiple Choice

Some changes in genes can help organisms _____

• Survive

• Mutate

• Rest

Multiple Choice

What is Natural Selection?

• Natural selection is the method by which all species are created equally.
• Natural selection is the process of random genetic mutations.
• Natural selection is the process by which organisms that are better adapted to their environment tend to survive and reproduce.
• Natural selection is the belief that all organisms are designed perfectly.

Multiple Choice

A yellow morph and green morph of an insect lives in the rainforest canopy. You would expect:

• the green population to increase and the yellow to decrease

• both populations should stay the same

• both populations will increase

• the green population to decrease and the yellow to increaseThis is a wrong answer

Multiple Choice

What word describes a trait that helps an organism survive in its environment?

• natural selection

• mutation

• camouflage

• adaptation

Multiple Choice

Dogs such as Chihuahuas are examples of....

• Artificial Selection 
• Natural Selection 
• Mutations 

Multiple Choice

Why are advantageous traits more likely to be passed onto offspring?

• Because they are more likely to survive and reproduce.

• Because they come from dominant alleles.

• Because they come from recessive alleles.

• Because the organism knew it needed that trait, survives, and passes it on.

Multiple Choice

Mutations are a change in what?

• DNA

• Proteins

• RNA

• tRNA

Multiple Choice

This is the process that ultimately creates new variations and changes in DNA; leads to the creation of new alleles

• Microevolution

• Mutation

• Gene flow

• Genetic drift

Multiple Choice

What is gene flow?

• A change in the gene pool due to chance

• A reduction in populations caused by natural disasters, disease, and hunting

• The addition or removal of genes due to individuals entering or leaving the population

• A change in gene frequencies when a new population arises from a few individuals

​2 Types: Founder Effect & Bottleneck Effect

Founder effect

• The founder effect occurs when a portion of the population (i.e. “founders”) separates from the old population to start a new population with different allele frequencies.

The Bottleneck Effect

• Occurs when only a few individuals survive and reduce variation in the gene pool of a population.

• The genetic structure of the survivors becomes the genetic structure of the entire population, which may be very different from the pre-disaster population.

Multiple Choice

When Christopher Columbus came to the Americas, he randomly chose 3 chickens from Spain to bring along. These 3 chickens were the only chickens to breed in the Americas for hundreds of year.

• Natural Selection

• Bottleneck

• Founder Effect

Multiple Choice

A drastic reduction in the size of a population that can change allele frequencies is called

• the bottleneck effect

• the founder effect

• the gene flow effect

• the Thanos effect

Multiple Choice

If a trait HELPS an organism survive, what may happen to it?

• It dies, cannot reproduce and DNA cannot be passed on

• It changes its traits to adapt and survive

• It survives, reproduces and passes on its DNA

Multiple Choice

There are two types of beetles: red beetles and green beetles. The beetles live in a forest full of trees. The birds in the forest seem to be eating ONLY the red beetles. The green beetles are not eaten. Which phenotype is favored and why?

• The green beetles because they stand out the most

• The red because they are more delicious so they are eaten more

• The red beetles because are not as big

• The green beetles are favored because they blend in with the trees

Multiple Choice

During the dry season, when water is low, an elephant will dig holes to find underground springs, drawing as much as two gallons at a time with its trunk. The water holes also give elephants access to important mineral sources buried deep below the surface.

• Overproduction of offspring

• Struggle to survive

• Inherited variation

• Non-random mating

Multiple Choice

What does the image represent?

• Genetic drift

• Mutation

• Adaptation

• Gene flow

Multiple Choice

What do we call ALL of the genetic information found in a population?

• Population

• Genetic Drift

• Evolution

• Gene pool

Multiple Choice

A trait or change in lifestyle that helps a plant or animal survive in its environment

• adaptation

• evolution

• homologous

• vestigial

Multiple Choice

One example of ___ is how moths that couldn't blend in with their environments as well as others died out over time.

• mutation

• natural selection

• extinction

Multiple Choice

Which of the following is a factor in natural selection?

• Individuals of species compete with one another to survive.
• All species are genetically diverse.
• Individuals better able to adapt to changes leave more offspring.
• All are correct 

Multiple Choice

Which adaptation this organism using?

• camouflage

• mimicry

• hide and seek

• use body covering

Multiple Choice

Which of the following is an example of the bottle neck effect?

• Bald Eagles are hunted until near extinction, population recovers.
• Small group of iguanas floats to an island, starts a new population.
• Red fox pups are more likely to survive in a snowy environment if they are born white.
• Farmer chooses seeds from largest apples to plant next year.  This results in larger apples from year to year.

Multiple Choice

Which of the following is an example of natural selection?

• Bald Eagles are hunted until near extinction, population recovers.

• Small group of iguanas floats to an island, starts a new population.

• Red fox pups are more likely to survive in a snowy environment if they are born white.

• Farmer chooses seeds from largest apples to plant next year. This results in larger apples from year to year.

Multiple Choice

One day a group of scientists collected a small group of brown anole lizards from a large group of the lizards.  Then they placed this small group of lizards on an island that had no brown anole lizards on it.  What is this an example of?

• Bottleneck Effect
• Hardy Effect
• Founder Effect
• None of These