Doctors would inject a woman's urine into the back of a female frog; if positive, the frog would lay eggs. Frog or "Hogben" tests were commonplace from the 1940s through the early 1960s.

These frogs put the “group ... There the female discharges a watery fluid, whips it to a foam with her back legs, and puts in her eggs. At this point, says Byrne, up to 20 more males ...

Eight fascinating animal species, such as Darwin's frog and mouthbrooding cichlids, exhibit unique reproductive strategies ...

These creatures are called amphibians. Frogs are amphibians. In the spring, female frogs lay thousands of eggs in pools or streams. Little black dots in clear jelly balls called frog spawn.

Frogs mate in a position called amplexus, with the smaller male clasping the female from behind in a ride that can last two days or more. As she lays eggs, he expels sperm to fertilize them.

During this period, the female frog feeds the tadpoles by producing infertile eggs until the tadpoles metamorphose. Mother mountain chicken frogs may feed their tadpoles 10-13 times during their ...