Question

Male pipefish have a brood pouch in which they carry and protect developing embryos. The gene patristacin plays a major role in the formation and function of the pouch. An evolutionary analysis revealed that patristacin is involved in liver and kidney function in all other fish (other male fish do not produce a brood pouch). This is an example of:

1) gene recruitment
2) irreducible complexity
3) gene duplication
4) antagonistic pleiotropy

Answer 1

The gene patristacin in pipefish, originally involved in liver and kidney functions in other fish, is an example of gene recruitment because it has been co-opted to develop and maintain the male pipefish's brood pouch in their polyandrous mating system. The correct option is 1.

Step-by-step explanation:

The evolutionary phenomenon shown by the gene patristacin in male pipefish is known as gene recruitment. This concept occurs when a gene, which originally has a particular function, is co-opted for a different function. In the case of the pipefish, the gene patristacin was initially involved in liver and kidney function in fish.

However, it has been recruited to play a crucial role in the development and functioning of the brood pouch in male pipefish, which is a characteristic feature of their polyandrous mating system where males carry and nurture the embryos. This adaptation allows females to mate with multiple males without the responsibility of incubating the fertilized eggs, as seen with the pipefish and seahorses, where the male receives eggs from the female, fertilizes them, and provides protection within a brood pouch.