For almost every species on Planet Earth, the female holds the majority of the responsibility when it comes to childcare. However, for seahorse, the table has turned. The dads are the ones who take on the role of the “mother” and gives birth to the young ones.
Asides from its peculiar structure, seahorse has a unique ability where the male seahorse take fathering to a whole new level: pregnancy. Seahorse is among the only three species on the entire planet where the male can experience true pregnancy. The structure that allows the male seahorse to carry babies is the brood pouch that it carries on its stomach. The pouch acts as a protective shelter for the infants to nourish and grow in the early stage of its development. The reproductive process usually begins with a male and female seahorse intertwine their tails and swimming together for up to as long as 8 hours where the female passes on her eggs to the male’s pouch. Inside the pouch, seahorse dad nourishes the eggs by regulating the temperature, blood flow and water salinity for the eggs as they hatch so the babies are as prepared as possible for life in the sea. He also makes sure to protect the eggs from infection, producing antibacterial and antifungal molecules to ward off pathogens.When the baby seahorses are ready to be born, the male undergoes muscular contractions in a process known as “fry” to expel the young ones much like how a mother goes through the labor process. In a way, the male seahorse has taken over the mothership role of the female and actually goes above and beyond what most, if not all females in the world, go through while giving birth. With around one week to go, seahorse dads start producing hatching signals. These signals cause the embryos to hatch out from their thin membranes and swim freely inside the brood pouch. As the embryos take up more room, the pouch begins to stretch, much like the belly of a pregnant human. Even though the dad goes an extra mile to take care of the enfants, neither the parent will provide any more care or protection for their babies once they are born. Therefore, infant seahorses are more susceptible to death as they are more likely to be eaten by the predators or swept away by the ocean due to their small size. In fact, only fewer than five infant seahorses in 1,000 actually survive to adulthood. However, the interesting fact is that when the male gives birth, they can actually have up to 2,000 babies at once. During the contraction, the male has to shoot out thousands of babies out of his stomach like a shotgun continuously. After the horrifying birth, the poor guy doesn’t even get to have a rest as the female loads him up with more eggs to repeat the whole process (talking about the best dad of the year). This explains why the ocean is littered with many infant seahorses as most of the them die early in their childhood.
The evolutionary theory helps explain why male seahorses carry this special ability. The theory explains that it helps them producing more babies efficiently in order to sustain their species. This helps them saving time because as the male carries out the pregnancy and childbirth process, the female can focus on making more eggs to prepare for the next courting. In a way this shows how the parent seahorses can share the load of creating new lives as oppose to how most females have to take on the role of child care all by her own. Scientists theorize that this ability might have helped the seahorses survive and evolve over the years. This eventually relates to our understanding of evolution in biology according to the Charles Darwin’s theory of natural selection. Even though the scientists haven’t been able to solve the mystery of why seahorse fathers get pregnant given that females have that responsibility in every other animal, this special ability certainly has helped them by allowing the parents to share the duties of childbirth which in turn helps them reproduce more efficiently.