Question

Kevin wants to add 3 more cichlids to the aquarium. He does not want to change the ratio among the three types of fish, so he will add more catfish and tetras as well. If he adds 3 more cichlids to the aquarium, how many more catfish and how many more tetras should he add to the aquarium?

A) Kevin should add 2 more catfish and 1 more tetra.
B) Kevin should add 3 more catfish and 3 more tetras.
C) Kevin should add 1 more catfish and 2 more tetras.
D) Kevin should add 1 more catfish and 1 more tetra.

Answer 1

Selective fishing for colorful fish will lead to a higher proportion of individuals with muted colors in the population, which could result in a genetic shift toward muted coloration as the dominant trait over time.

Step-by-step explanation:

The scenario described involves selective fishing, which can have an impact on the genetic diversity and traits within a fish population in the ecosystem. Since the local fisherman selectively captures colorful fish, the remaining population in the lake will have a higher proportion of individuals with muted colors. Over time, this selective removal of the colorful fish could lead to genetic changes in the population, resulting in a shift toward muted coloration as the dominant trait, if such coloration is heritable. This is an example of human-induced evolutionary change where the fishing practices are acting as a selective pressure on the fish population.

Additionally, referring to the concept of adaptive radiation as outlined in FIGURE 4.16, the removal of certain phenotypes (colorful fish) can influence the direction of this process, potentially favoring the survival and reproduction of less colorful fish if their traits are advantageous under the new conditions imposed by the fisherman's actions.