Male seahorses become pregnant. They are part of the only family in the animal kingdom that do so: the Syngnathidae family. Others in this group include pipefish and weedy sea dragons.
Seahorses carry a female's eggs in a specialised pouch. Females are therefore very choosy when it comes to picking the male, preferring larger males with the most ornaments.
To woo her, a male will often perform a special dance (as in the video below). His goal is to entice any potential females looking to lay her eggs in his pouch. He will then fertilise these eggs and care for them as they grow.
We now have greater insight into how male seahorses nurture their developing embryos.
A male will provide vital nutrients to the hundreds of tiny offspring growing in his pouch. These include energy providing fats and calcium, necessary for bone development.
"Surprisingly, seahorse dads do a lot of the same things human mums do," said Camilla Whittington, lead author of a new study looking into male pregnancies.
"Seahorse babies get a lot of nutrients via the egg yolk provided by their mothers but the pouch of the fathers has also evolved to meet the complex challenges of providing additional nutrients and immunological protection, and ensuring gas exchange and waste removal."
The study, published in the journal Molecular Biology and Evolution, also monitored the genetic changes that occured as the embryos developed.
Again, here the process was comparible to humans.
"We have evolved independently to meet these challenges, but our research suggests that even distantly related animals use similar genes to manage pregnancy and produce healthy offspring," says Whittington.
