Some tadpoles don’t poop for the primary weeks of their lives. Not less than, that’s the case for Eiffinger’s tree frogs (Kurixalus eiffingeri), scientists report September 22 in Ecology.

Eiffinger’s tree frogs are tiny frogs that dwell in Taiwan and on two Japanese islands: Ishigaki and Iriomote. The tree-dwelling amphibians lay their eggs in puny puddles, which are sometimes nestled in plant stems, tree hollows and bamboo stumps.

As soon as the tadpoles hatch, they spend their early lives in these puddles. Nonetheless, in swimming pools as small as these, there’s not a whole lot of water to dilute ammonia — a poisonous chemical animals launch once they pee or poop.

Bun Ito and Yasukazu Okada, biologists from Nagoya College in Japan, now have uncovered the tadpoles’ secret sanitation technique — self-induced constipation. The tadpoles retailer their poop in an intestinal pouch till they begin to metamorphize into full-fledged frogs.

Ito and Okada raised tadpoles from 4 totally different frog species in makeshift nurseries. As soon as the experiment started, they moved the tadpoles to smaller cribs, plastic instances with a bit of greater than a tablespoon of water. The group measured and in contrast how a lot ammonia every species launched. In addition they measured the quantity of ammonia every species saved of their guts.

Eiffinger’s tree frog tadpoles launched lower than half as a lot ammonia on common than the species that launched essentially the most. And in contrast with two of the opposite species, the tadpoles saved extra ammonia of their guts. The researchers be aware that not like Eiffinger’s tree frogs, the opposite species sometimes lay their eggs in open ponds the place ammonia is definitely diluted.

“The conduct doubtless serves to stop contamination of small water our bodies,” Ito says. Some ammonia nonetheless seeped into the tree frogs’ water, probably by means of their pee.

It seems Eiffinger’s tree frog tadpoles have one other superpower: Experiments confirmed that they’ll survive in greater ammonia concentrations than one of many different species included within the examine, Dryophytes japonicus, higher often called the Japanese tree frog. Whereas which may appear counterintuitive, given the tadpoles’ poopless interval, Ito notes that typically the tadpoles share their cribs with different animals, similar to mosquito larvae, which additionally launch ammonia.

“We hypothesize that the tadpoles have developed a tolerance to ammonia as a twin protection mechanism,” says Ito, “each towards ammonia produced by different organisms and the ammonia they generate themselves.”