Question

Which of the following statements describes an ultimate cause?

a.) Birds often show elaborate courtship displays in response to visual cues provided by a willing mate.
b.) People sleep at night because a molecule that accumulates during the day has an effect on the sleep centers of the brain.
c.) Birds have hollow bones because hollow bones increased the fitness of their ancestors by allowing them to run faster and capture prey more efficiently.
d.) Snowshoe hares turn white in winter in response to changes in day length.

Answer 1

An ultimate cause in biology is an evolutionary explanation for a biological trait. The ultimate cause example given is that birds have hollow bones because it provided a survival and reproduction advantage to their ancestors.

Step-by-step explanation:

The statement that describes an ultimate cause is: Birds have hollow bones because hollow bones increased the fitness of their ancestors by allowing them to run faster and capture prey more efficiently. This explains the evolutionary rationale behind a physical adaptation in birds, connecting a biological trait to the fitness advantage it provided in the past.

An ultimate cause in biology refers to the evolutionary explanations for why a certain trait exists based on the historical advantages it conferred, likely leading to natural selection. For example, hollow bones in birds make them lighter, facilitating flight and efficient movement over time. These evolutionary advantages manifest into the species' current form and functions; for example, a good sense of hearing might have been selected for because it would be more useful than good vision when hunting in the dark. This aspect of natural selection is distinct from immediate or proximate causes, which involve current physiological mechanisms, like circadian rhythms influencing daily behaviors.