This type of selection occurs when humans choose which organisms reproduce.
What is artificial selection?
This process happens when organisms with helpful traits survive and reproduce more often.
What is natural selection?
A trait that helps an organism survive in its environment is called a(n):
What is an adaptation
Differences in traits within a population are called:
What is genetic variation?
Birds that eat insects become active earlier in spring. When should insects emerge to survive?
Later in the spring
Farmers breed plants to grow larger fruits. This is an example of what type of selection?
What is artificial selection?
Some mice are light-colored and some are dark-colored. Hawks can easily see the light mice. Which mice are more likely to survive?
What are dark-colored mice?
Long legs help a deer run faster from predators. Is this trait helpful or harmful?
Helpful
Why is genetic variation important for a species?
It increases the chance some individuals survive environmental changes.
A species of beetle varies in shell thickness. Birds easily crush beetles with thin shells.
Which trait will most likely become more common over time?
Thicker shells
Dogs were bred from wolves to help with hunting and herding. Who selected these traits?
Humans
A population of insects includes some that survive pesticide exposure. After many years, most insects survive the pesticide. Why?
Because insects with resistance survived and reproduced.
Can an organism change its traits during its lifetime and pass them on?
No.
A litter of puppies looks different from one another. What causes this?
Genetic variation
A group of fish lives in cold water. Over time, the water temperature slowly decreases.
Which trait will most likely increase in the population?
Thicker scales
Why is artificial selection different from natural selection?
Because humans choose the traits instead of the environment.
Why does natural selection happen over many generations instead of one lifetime?
Because traits are passed down through reproduction over generations.
Why do helpful traits become more common in a population?
Because organisms with those traits survive and reproduce more.
If all organisms in a population were identical, what would happen when the environment changes?
The population would be less likely to survive.
A population of rabbits varies in running speed. Predators hunt these rabbits by chasing them.
Which rabbits are most likely to survive over many generations?
Faster rabbits