A Somersault for Spawning
The Surinam toad, Pipa pipa, is a fully aquatic amphibian that has an exceptionally flat body, perfectly resembling a dead leaf on the bottom of slow-moving streams in the Amazon Basin. This camouflage hides it from predators, but its reproductive method is is its reproduction. Mating begins when a male approaches a female and grasps her in a position called inguinal amplexus, wrapping his forelimbs around her waist. He signals his intent not with croaks, but with a series of sharp, metallic clicks produced by snapping the hyoid bone in his throat.
What follows is a complex underwater sequence. The pair performs a series of 15 to 18 vertical loops or somersaults. As they float upside down during these arcs, the female releases a small clutch of 3 to 10 eggs. These eggs land on the male's belly. As they complete the loop and turn right-side up, the male fertilizes the eggs and gently rolls them onto the female's back. The process is repeated for hours until 60 to 100 eggs are securely in place. A sticky secretion helps the eggs adhere to her dorsal skin, which has become soft and swollen in preparation.