Finches in the Galapagos experienced __________selection on beak depth following a drought; the African finch P. ostrinus experienced __________ selection on beak size because it eats either very small, soft seeds or much larger, hard seeds.

a. stabilizing, directional

b. sexual, disruptive

c. directional, disruptive

d. disruptive, directional

e. stabilizing, disruptive

The age of the Earth has been established through the use of ________, in which scientists test for the ________ of parent and daughter elements in a given sample of rock or other material.

________ features are features in different species that are the same in structure owing to inheritance from a ________.

The auricular muscles of human beings and the wings of ostriches are examples of _______ characters.

True or false: Charles Darwin was the first person to perceive common descent with modification.

The co-discoverer of natural selection was ________.

Following the publication of On the Origin of Species, the evolutionary principle of ________ was quickly accepted by most scientists, but the importance of __________ would not be accepted by most authorities until midway through the twentieth century.

The principle of common descent with modification holds that groups of living things can undergo modifications that, over time, can lead to the formation of new _______ and that all living things on Earth are descended from a _______.

The principle of natural selection holds that some traits will confer a _______ to individual organisms and that these traits will accordingly become more _______ over time in a population of organisms.

Evolutionary theory supports the idea that humans are _______ other organisms and thus are not _______ from other living things.

Using evolutionary principles, explain why large ears might be expected to evolve in a terrestrial plant eater such as a rabbit or deer but not in an aquatic mammal such as a seal.