If you’ve ever gone tadpole hunting, you may have seen some frog or toad eggs sitting in the water. Often they’ll be clinging to a piece of vegetation, or something else, to keep them from drifting far. The parents usually abandon the eggs shortly after they’re laid, and the eggs sit and develop, basically alone, for days to weeks. Then the tadpoles hatch. Over time, they’ll grow up to be little toadlets or froglets.
But there are several fascinating exceptions to this typical scenario. One is the Surinam toad, also known as the star-fingered toad (Pipa pipa). It’s a South American toad that has fully-developed baby toads “hatch” out of its skin.
After fertilizing the eggs, the male Surinam toad actually pushes them onto the back of the female toad. They stick to her skin and embed in it. Her skin changes over the next few days to form pockets around the eggs, making her back look like a bizarre honeycomb, and then completely encloses the eggs. The eggs hatch into tadpoles under her skin, and later “hatch” from her skin as completely developed little toads.
If you’re a frog or toad, it’s definitely hard to beat the Surinam toad when it comes to parental investment in one’s offspring!
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