McGuire's find confirms speculation that stretched back decades. He had first crossed paths with these animals in 1998, when he arrived on the island of Sulawesi, but wasn't able to observe them giving birth until now.
These fanged frogs - named after toothy bits sprouting from their jaws, which the frogs use to spar - aren't the only frogs who spawn with an atypical method. A few frogs lay fertilized eggs, and others skip the tadpole phase completely, entering the world as froglets. "There are lots of weird modifications to this standard mode of mating," McGuire said in a statement. McGuire and his Indonesian and Canadian colleagues published a description of the frogs in late December in the journal PLOS ONE.