Question

facultative mutualism is:
a a type of mutualism in which the interacting species derive benefit from each other but are not fully dependent on each other for survival.
b a type of mutualism in which both species cannot survive without each other
c a type of mutualism in which one species’ survival depends on the other, but the other is indifferent
d a type of mutualism where one species of bird agrees to raise the offspring of another

Explanation:

To determine the correct answer, we analyze the definition of facultative mutualism. Facultative mutualism is a type of mutualistic interaction where the participating species gain benefits from each other but are not entirely reliant on one another for their survival.

• Option A matches this definition as it states the interacting species derive benefit but are not fully dependent.
• Option B describes obligate mutualism (where species are dependent on each other for survival).
• Option C does not fit the mutualism concept (mutualism requires both to benefit, not one being indifferent).
• Option D is not a standard definition of facultative mutualism.

Answer:

A. A type of mutualism in which the interacting species derive benefit from each other but are not fully dependent on each other for survival.