Do all frogs produce spawn?
In short, yes! Female frogs produce eggs that are then fertilised by males. The resulting gelatinous blob, which typically contains lots of individual eggs, is called frogspawn. For most frog species, the spawn then develops wherever it is deposited – in ponds or puddles, for example – but some species buck the trend.
Females of the (sadly extinct) gastric brooding frog, which used to live in eastern Australia, would swallow their fertilised spawn and convert their stomachs into makeshift wombs. Unbothered by predators, the emerging tadpoles would then develop entirely inside their mothers, who would then burp up the fully formed froglets. Meanwhile, male Darwin’s frogs, which are alive and kicking in Chile and Argentina, gulp in mouthfuls of fertilised spawn and then let the emerging tadpoles develop inside their enlarged vocal sacs. Several weeks later, these frog dads also ‘give birth’ via their mouths.