Question

One of the functions of pelvic spines in the ocean is to protect stickleback from larger fish predators. Based on this knowledge, which statement might be a possible explanation for the difference in pelvic spines between Bear Paw Lake and Frog Lake sticklebacks?

A. Bear Paw Lake sticklebacks have longer pelvic spines because they face more significant predation pressure from large fish.
B. Frog Lake sticklebacks have shorter pelvic spines because they are less vulnerable to predation.
C. Bear Paw Lake sticklebacks have shorter pelvic spines because they are better adapted to their environment.
D. Frog Lake sticklebacks have longer pelvic spines because they are more aggressive in defending against predators.

Answer 1

The lengths of pelvic spines in sticklebacks from different lakes could indicate varying predation pressures or environmental factors, with longer spines suggesting higher predation risk and shorter spines indicating less vulnerability or different adaptations.

Step-by-step explanation:

The difference in pelvic spines between Bear Paw Lake and Frog Lake sticklebacks can be associated with their respective environmental pressures and predation risks.

If Bear Paw Lake sticklebacks have longer pelvic spines, one possible explanation is that they face more significant predation from large fish, using those spines for protection. This aligns with option A. Conversely, if Frog Lake sticklebacks have shorter pelvic spines, it might suggest they are less vulnerable to predation or that there are other selective pressures influencing spine length, such as environmental factors or different predatory species which do not select for longer spines, corresponding to option B.