Evolution

Similarities in the structures of two different species provide evidence that the species evolved from a common ancestor. This type of evidence includes similar structures that have different functions. Which of the following pairs of features have a similar structure but have a different function in each organism?

• A. A dolphin fin and a shark fin

• B. Human fingernails and monkey fingernails

• C. The front leg of a cat and the wing of a bat

• D. The wing of a bumble bee and the wing of a bird

Which of these claims best describes what Charles Darwin observed in the Galapagos Islands?

• A. The finches on the islands ate seeds and nuts but no insects.

• B. The finches on the island were the same as the finches in Ecuador.

• C. The finch population on each island was unique.

• D. The finches could only produce offspring with the finches from other islands

If two spotted salamanders of the same species live in different areas which of the following is used to describe the difference between them?

• A. Overpopulation

• A. Population

• A. Extinction

• A. Genetic variation

A scientist described two modern-day species as sharing a common ancestor. Which is a valid claim about what it means when two species share a common ancestor?

• A .Both species evolved from one species that lived in the past.

• B. The two species are actually the same species.

• C One of the species evolved from the other species.

• D. The two species share all the same traits.

Which of the following is least likely to cause a species to become extinct due to changes in the environment?

• A. Less genetic variation

• B. More genetic variation

• C. Specific food preferences

• D. More competition for food

When farmers want two desirable traits in cows, they often breed individuals that have those traits in the hopes that the offspring will have both desirable traits. What is this practice called?

• A. Genetic variation

• B. Adaptation

• C. Artificial selection

• D. Natural selection

Ashley observes a sparrow’s nest in a shrub outside her home. The week Ashley finds the nest, she notes that there are six eggs present. When she returns two weeks later, she notices only five of the eggs hatched. Upon visiting the nest a week after that, she finds that three of the chicks learned to fly, and the other two disappeared. What part of natural selection did Ashley observe?

• A. Adaptation

• B. Overproduction

• C. Selection

• D. Genetic variation

Polar bears live in the Arctic. Ice in the Arctic is melting rapidly, reducing the range in which the polar bears can live. If polar bears do not have adaptations that allow them to survive these changes, what may happen to the polar bears?

• A. They may overpopulate

• B. They may change the environment

• C. They may go extinct

• D. They may become another species

A species of rodent lives in a moist forest climate. Over time, the climate becomes drier and more desert-like. Which of these adaptations would most likely improve the chances that the rodent species could survive as its environment changes?

• A. Being able to eat plants that survive in the changed environment

• B. Being able to eat only one type of berry

• C. Living above ground in damp areas

• D. Having dark hair and small ears

Which of these best describes the tiny leg bones that some whales have, which do NOT aid in their movement or serve any other function?

• A. Structures that grow and improve function as they are used

• B. Structures that function at certain times of the year in certain conditions

• C. Structures that will become adaptations when the environment changes

• D. Structures that have lost all or most of their function over evolutionary time