What is an evolutionary adaptation?
a. A trait that improves the fitness of its bearer, compared with individuals without the trait
b. A trait that changes in response to environmental influences within the individual's lifetime
c. The ability of an individual to adjust to its environment
d. A trait that an individual wants so that it can survive

Coral reefs are biodiverse ecosystems that provide food, income, coastal protection, and many other services to millions of people. Yet coral reefs are under threat from human impacts such as climate change—many corals cannot tolerate the warming ocean water and have suffered massive 'bleaching' events, which can be fatal. Researchers have discovered that some corals have the capacity to acclimatize to warmer water, while other corals do not. The researchers fear that because corals are long-lived colonial animals and thus evolve slowly, they may not be able to adapt to global warming fast enough to avoid extinction. Explain how the difference between acclimatize and adapt is important to the fate of corals.

The geneticist James Crow wrote that successful scientific theories have the following characteristics: (1) They explain otherwise puzzling observations; (2) they provide connections between otherwise disparate observations; (3) they make predictions that can be tested; and (4) they are heuristic, meaning that they open up new avenues of theory and experimentation. Crow added two other elements of scientific theories that he considered important on a personal, emotional level: (5) They should be elegant, in the sense of being simple and powerful; and (6) they should have an element of surprise. How well does the theory of evolution by natural selection fulfill these six criteria?