Share on facebook
Share on twitter
Share on linkedin
Share on whatsapp
Share on email

23 December 2021

Pregnant dads

Seahorses: one of the only species in which the male gets pregnant and gives birth.

Seahorses are teleost fish, even though most people are only vaguely aware of this fact, confounded by the horse-like head, a prehensile tail and an upright posture swim! Seahorses are viviparous fish – i.e. produce young which develop within the body of the parent – their reproduction is unique among vertebrates because these animals have refined paternal care to such an extent that the males become pregnant.

A female seahorse transfers eggs into the male’s brood pouch, which is a skin pocket situated on the male’s abdomen or tail (depending on the species), the eggs are subsequently fertilized and the embryonic development is initiated. After mating the opening is sealed and the embryos develop inside the pouch, isolated from the external marine environment, effectively preventing more than one female from depositing their eggs into a male’s pouch. After the mating has occurred, however, the circulating androgen concentration decreases rapidly and the male has to perform a completely different function, namely, to support pregnancy. After 2-3 weeks, depending on the species, the pregnant males can give birth to up to 1,000 tiny seahorses.

Also read:

The PhD Annalisa Azzola explains the consequences of climate change on these fragile marine organisms

“Corals are the ‘architects’ of the marine environment” explains Annalisa Azzola, PhD in Marine Science and Technologies at DISTAV, University of…

Fin whale songs could help scientists map what lies below the seafloor

Their songs are loud enough to penetrate Earth’s crust and reveal deep structures. Fin whale songs can be up to…

Scientists inquired how marine animals use light to camouflage themselves.

The coloration of animals in the ocean follows a surprisingly regular pattern by depth, most likely tied to how light…