Which of the following best explains the role of deep sea coral reefs in the environment?
a. they are responsible for fouling fishing lines.
b. they are a quick-growing food source for deep water predators.
c. they provide a critical habitat for many other organisms.
d. they are a record of past climate conditions.

Which of the following observation darwin shape his concept of descent with modification? a) species diversity declines farther from the equator. b) fewer species live on islands than on the nearest continents. c) birds live on islands located farther from the mainland than the bird's maximum nonstop flight distance. d) south american temperate plants are more similar to the tropical plants of south america than to the temperate plants of europe. e) earthquakes reshape life by causing mass extinctions.