Question

In studies on the pipefish Nerophis ophidion, females are larger than males and appear to be under greater sexual selection pressure than males. The females have two traits that male pipefish of the species lack. What are these two traits?

1) dark blue stripes and lateral spines

2) bright orange stripes and skin folds on their bellies

3) dark blue stripes and skin folds on their bellies

4) lateral spines and skin folds on their bellies

Answer 1

Female pipefish Nerophis ophidion possess bright orange stripes and skin folds on their bellies as traits of sexual dimorphism, reflecting greater sexual selection pressure on females.

Step-by-step explanation:

The student is asking about the sexual dimorphism traits in the pipefish Nerophis ophidion, where females are larger and experience greater sexual selection pressure than males. In many species, sexual dimorphism can result from variance in reproductive success; in some species, such as pipefish and seahorses, females may provide eggs to several males without carrying fertilized eggs, leading to polyandrous systems. This question reflects an understanding of biology, specifically concerning sexual dimorphism and mating systems.

The two traits that female Nerophis ophidion have which are lacking in males are bright orange stripes and skin folds on their bellies. This reflects the greater sexual selection pressure on females in some species, including those where roles are reversed and females are more elaborately decorated or larger than males, to increase reproductive success.