11. What is the purpose of natural selection?
to limit the genetic variation of a population
to increase the frequency of desired alleles in a population
to keep life going even as the environment changes
12. Which is an example of artificial selection?
A farmer crosses two kinds of corn. He produces a new, better tasting type of corn.
A flood drowns most of the lizards in an area. Only lizards that can swim live to reproduce.
Two male wild turkeys fight. The weaker one is killed. The winner mates with all the females.
13. A fossil found under a layer of rock is usually _____.
evolved from the rock
younger than the rock
older than the rock
made from a different type of rock
14. What is the creation of new combinations of alleles called?
gene flow
genetic drift
recombination
mutation
15. Which evolutionary mechanism caused the increase in dark-colored Biston betularia moths in England in the 1800s?
gene flow
genetic drift
natural selection
overproduction
16. Natural selection is based on Darwin’s observation that individuals most likely to survive and reproduce are those _____.
with many offspring that have similar traits
with traits best suited to their current environment
that descended from previous life forms
that do not resemble their ancestors
17. At one time, dinosaurs lived on Earth. Today they are extinct. This relates to _____.
both macroevolution and microevolution
microevolution
macroevolution
18. An orphaned female lion joins a band of lions. The addition of her genes to their gene pool is _____.
natural selection
recombination
genetic drift
gene flow
19. Which is an example of a population?
all the squirrels in North America and Europe
all the rose bushes around the world
all the sugar maple trees in a state park
all the species of organisms in one state
20. Which of the following explains Darwin’s theory of natural selection?
Individuals in a population with traits best suited for that environment survive and increase in number.
More recent species of organisms are changed descendants of earlier species.
Present organisms are related to and descended from past organisms.
