Problem 5 - Biology: The Dynamic Science

Question

A keystone species: a. is usually a primary producer. b. has a critically important role in determining the species composition of its community. c. is always a predator. d. usually reduces the species diversity in a community. e. usually exhibits aposematic coloration.

Step-by-Step Solution

Answer

The correct answer is (b) - A keystone species has a critically important role in determining the species composition of its community.

Step 1: Understand the characteristics of a keystone species

A keystone species is one that has a large impact on its environment and can effect significant changes in its community if removed. They help to maintain local biodiversity and can influence the types and numbers of various other species in their habitat. They are not necessarily the most numerous nor the largest species.

Step 2: Evaluate each alternative given in the exercise

Now, evaluate each answer choice in the light of our understanding of a keystone species. (a) is not necessarily correct because a keystone species can be a producer, consumer, or decomposer. It's not always a primary producer. (b) seems right as it's in line with our understanding that a keystone species plays a crucial role in determining species composition in its community. (c) is also incorrect because a keystone species does not have to be a predator. (d) appears incorrect, as generally keystone species increase the diversity by their actions. Lastly, (e) is not true as keystone species aren't usually identified by their aposematic coloration.

Step 3: Choose the correct answer

Among all the given options, (b) aligns best with the concept of a keystone species. Hence, we can conclude that the correct answer is (b).