Stickleback fish exhibit variation in a morphological trait known as gill rakers. Fish with long gill rakers are very good at eating plankton, and fish with short gill rakers are good at eating deep-water invertebrates. However, fish with intermediate-length gill rakers are poor at eating either type of food. Fish that are better at consuming food have higher survival and reproduction rates than poorer consumers. Based on this information, what type of selection is likely acting on stickleback gill raker length? Group of answer choices

Question

Jaylynn Grant

Biology

16 March, 19:58

Stickleback fish exhibit variation in a morphological trait known as gill rakers. Fish with long gill rakers are very good at eating plankton, and fish with short gill rakers are good at eating deep-water invertebrates. However, fish with intermediate-length gill rakers are poor at eating either type of food. Fish that are better at consuming food have higher survival and reproduction rates than poorer consumers. Based on this information, what type of selection is likely acting on stickleback gill raker length? Group of answer choices

+2

Answers (1)

Know the Answer?

Carly Petersen · Answer 1

disruptive selection

Explanation:

Disruptive or diversifying selection is a term used to describe population genetic changes that simultaneously favor individuals at both ends of the distribution. When disruptive selection operates, individuals at the extremes contribute more offspring (children) than those with intermediate characteristics, producing two peaks in the distribution on a graph. In this case, the extremes are favored. As an example, we can cite the fish shown in the question, where fish with long rakers are very good at eating plankton, and fish with short rakers are good at deepwater invertebrates. However, fish with intermediate gill rakers are poor in eating any kind of food.