Caecilians are amphibians that look superficially like very giant earthworms. New analysis means that at the least one species of caecilian additionally produces “milk” for its hatchlings.

Photo by Carlos Jared

conceal caption

toggle caption

Photo by Carlos Jared

Caecilians are amphibians that look superficially like very giant earthworms. New analysis means that at the least one species of caecilian additionally produces “milk” for its hatchlings.

Photo by Carlos Jared

A species of worm-like amphibian has been caught on digital camera feeding milk to its younger.

The creature, often known as a caecilian, lives underground. Researchers imagine that the animal developed the flexibility to supply a milk-like substance independently of mammals, who’re universally identified for feeding milk to their younger.

Caecilians are descended from the identical lineage as frogs and salamanders. Hundreds of thousands and thousands of years in the past, their ancestors burrowed deep into the bottom. They misplaced their legs, their eyes largely stopped working, and their our bodies turned lengthy and segmented. A contemporary caecilian seems to be just a little like a protracted shimmering earthworm with a head, which has led some to name them icky.

That’s a characterization Marta Antoniazzi completely rejects.

“I really don’t agree that they are disgusting,” says Marta Antoniazzi, a biologist on the Instituto Butantan, in Sao Paulo, Brazil. Brazil is residence to plenty of caecilians and Antoniazzi is a fan.

“They are kind of elegant, and they have a shiny body and a very nice face,” she says.

But wait, there’s extra.

The explicit caecilian species that Antoniazzi and her colleagues examine known as Siphonops annulatus. Mothers of this species give delivery to broods of wriggly infants who then proceed to eat their very own mom’s pores and skin off.

“Once a week, they can eat her skin,” says Pedro Luiz Mailho-Fontana, a researcher on the Insituto Butantan who was concerned within the examine.

This does not appear to hassle mama, and the infants get plenty of vitamin from the pores and skin.

Carlos Jared directs the institute’s division of structural biology and leads the group that was finding out the caecilians. As he was watching this fascinating course of, he could not assist however discover the wriggly little infants had a ton of vitality.

“They are so, so active, it’s impossible to eat only once or twice per week,” he says.

So the group caught a digital camera within the nest and began watching. And fairly quickly, they observed the infants had been gathering round one explicit spot.

“The babies prefer to go to the tail of the mother,” he says.

And that is once they noticed it. A secretion coming from the tail: “A kind of substance, like milk.”

Upon additional examine, the group discovered that the milk contained lipids and sugars much like mammalian milk. It was basically offering the identical perform.

“It’s a very unusual form of nutrition” for an egg-laying animal, says Mailho-Fontana.

The group published their results on this week’s difficulty of the Journal Science.

Marvalee Wake, a professor of integrative biology on the University of California at Berkeley, who was not concerned with the examine, says that this species of caecilian has advanced to take care of an analogous drawback confronted by human infants. Just like people, the little ones are born lengthy earlier than they will fend for themselves. They’re susceptible. And as a way to assist them develop, whereas conserving them shut, their mom has developed a milk-ish fluid.

“This is convergent evolution,” she says.

Convergent evolution is the method by which very completely different species can evolve comparable traits.

But is it actually milk?

The Brazilian group does not say whether or not the milk meets FDA requirements, but it surely does include lipids and sugars. Wake says she thinks it counts.

“If it has all these basic subunits, it’s convergent evolution on a nutritive material, and that’s what it’s all about,” she says.

For Antoniazzi, caecilians are an exquisite reminder that very completely different animals, like puppies and underground worm-amphibians, can share quite a bit in widespread.

“Nature is very creative,” she says. “Sometimes it gives the same solution to different groups of animals.”