Indian Frogs Discover Gross New Way to Have Sex
It's called the dorsal straddle, and researchers spent 320 hours filming it
By Michael Harthorne,  Newser Staff
Posted Jun 14, 2016 5:15 PM CDT

(Newser) – A group of dedicated researchers have discovered a seventh position used by mating frogs and toads, and it's—in scientific terms—super gross. A study published Tuesday in PeerJ describes the new position, the dorsal straddle, as “a loose form of contact in which the male sits on the dorsum of the female prior to oviposition but without clasping her." Basically, the male frog gets on the female's back without putting his front limbs on her, according to the AP. The male releases his sperm onto the female's back after 13 or so minutes and leaves. She lays her eggs then lets the male's sperm run down her back to fertilize them. The dorsal straddle was observed in Bombay night frogs, and it was a "very challenging experience," researcher Sathyabhama Das Biju tells Live Science.

Bombay night frogs only mate in India's Western Ghats over flooded streams during monsoon season. So researchers spent eight hours a night for 40 nights standing in streams, filming frog sex, and trying to keep their infrared cameras dry. It could take hours for just one frog couple to mate, as they repeatedly fell into the water and would have to climb back to their original position to continue mating. All that work—and sexual innovation—was largely for naught, as 12 of the 15 fertilized egg clutches recorded by researchers were promptly eaten by other animals. At least the Bombay night frog and its dorsal straddle might get an Urban Dictionary entry out of it. (Meet the world's first known venomous frog.)