The Animal Kingdom's Most Unusual Mother

May 09, 2008

Just in time for Mother's Day comes news about what could be the world's most unusual mother—the seahorse. Males of this species experience all of the burdens, and rewards, of motherhood, since they are the ones that give birth.

The process involves role reversals right from the start, since it's the female who inserts her ovipositor into the male's brood pouch and deposits her unfertilized eggs. The male then squirts his sperm into the pouch, and after that is when the "fun" begins for him.

Like the nauseating, weird food craving and bloated-feeling pregnancies experienced by women, he must then haul around the developing offspring, which he controls at every level. According to Texas A&M University evolutionary biology researcher Adam Jones and his team, the male keeps blood flowing around the embryos, controls the salt concentrations in the pouch, and provides oxygen and nutrition to his family-to-be through a placenta-like structure until he gives birth.

Human women might already be thinking that's a pretty good deal, but that's not all. Male seahorses are completely monogamous. They additionally are less competitive than most males of other species.

“Females (among seahorses) exhibit a competitive behavior that’s normally a male-type attribute, and males end up being choosy, which is normally a more female-type attribute,” Jones said.

He and his colleagues are studying seahorse genetics, to see how male pregnancy might have evolved in the first place.

In the meantime, Happy Mother's Day to all of the seahorse moms of the world. Here's proof that the males do indeed give birth. The footage goes on for a while, but imagine what pushing out all of those kids must be like for him!

Comments

[Patty]

Awesome video. BUT: why do they call it a male?

[Jen Viegas]

Thanks, Patty. Good question. Males are defined as animals that can produce gametes (sperm) that can fertilize female gametes (eggs). Since the "mother seahorse" is still the one that produces sperm and fertilizes the female's eggs, mom in this rare case is a he.