Seahorses have a rather unusual mating ritual in that the male undergoes pregnancy. This is something of an anomaly in nature – in fact, seahorses are the only known animals with mating rituals of this sort.
Why do male seahorses get pregnant?
Scientists don’t have a conclusive asnwer to why male seahorses give birth, but they theorize that this is one of the tactics they use to help the species survive.
One theory suggest that males carry the baby which gives the species the ability to create more babies quickly. After the female deposits all her eggs into his pouch, she needs time to make more eggs. And while he’s carrying one set of eggs, she’s creating more egg and by the time the male gives birth, they are ready to replicate the process all over again.
How do male seahorses get pregnant?
When seahorses mate, the female deposits her egg into the male’s pouch; he is then responsible for fertilizing it, and carrying it until the offspring is born.
Male have a thickened pouch, which carries the embryo and provides it with necessary nutrients and a supply of oxygen. This is similar to how, in most mammals, the fetus receives its nutrients from the placenta of the mother.
Do male seahorses have a uterus?
While male seahorses don’t have a uterus, their pouches act in a manner similar to how a uterus does. The pouch contains the same genes that are present in a female uterus, called homologues. Thus, the egg develops in the same was as it would in a female body.
Some other ways in which the pouch resembles a working uterus are:
• It regulates the temperature and blood pressure for the embryo.
• It provides the developing egg with a sufficient amount of nutrients and oxygen.
• It has genes that protect the embryo from bacteria and infections.
So, while male seahorses don’t have an actual uterus, the pouch does just as good of as job at facilitating the embryo.
How does a seahorse give birth?
Male seahorses birth their offspring just like the females of most typical species do. First, they carry the egg in their pouch for two to four weeks while it develops. Then, a week before the fry is ready to be born, the male seahorse’s body begins to produce hatching signals. These signals cause the embryo to break out of the thin membrane that encloses it.
Once the embryo is released from the membrane, it can start to swim freely in its carrier’s pouch. Now, the embryo requires more room to move. This is when the males pouch expands; just like how a female’s stomach swells to hold a fetus.
During this time, the hormone ‘oestrogen’ is secreted by the male. This sends genetic signals, which start the process of birth.
A baby seahorse exits the pouch of its father in a process similar to how a baby exits its mother’s womb. This process involves the contraction of certain abdominal muscles, which push the fry out of its parent’s body.
How many seahorses are born at once?
Male seahorse’s gestation period lasts for two to four weeks and can deliver anywhere between five to a thousand fry. However fewer than 5 in 1000 survive to adulthood.
Seahorses typically give birth during the night, and they’re usually ready by morning to receive more eggs and repeat the process all over again.
Seahorses mate for life
Seahorses are a monogamous species by nature; wild seahorses are particularly so. Scientists have speculated as to why this may be, and the general scientific consensus is that seahorses actually don’t find mates all that easily. This is because:
• They tend to spend most of their time camouflaged, to avoid predators.
• They are not the best of swimmers, and consequently don’t travel far underwater.
Another reason for their life long relationships is that seahorses have a natural tendency towards remaining loyal to one another. While this may sound quite sweet, there’s actually a practical reason behind it – monogamy means that seahorses have the opportunity to produce a greater number of offspring during the mating season.