Big Tadpoles Eat the Little Ones
If food is scarce, tadpoles use extreme methods. Large tadpoles will eat their smaller siblings, growing even bigger. Biologically speaking, the cannibalism makes sense.
It looks idyllic in the spring, when ponds and lakes start to fill with tadpoles, which swim about eating algae and other tiny creatures. But in reality, tadpoles participate in a merciless race for life and death.
All tadpoles hatch within a few days, and from that very moment, everything is about eating as much as possible as quickly as possible, so they can be converted into frogs or toads and climb ashore – preferably before any of their siblings, as tadpoles are not afraid of using dirty tricks, particularly not if times are rough, because the pond is drying up, etc. Under such circumstances, they forget that they love their siblings, turning into cannibals. Some tadpoles are lucky enough to be in slightly bigger eggs and are hence larger than the rest, and they mercilessly take advantage of the situation, consuming their smaller peers. This makes them grow still bigger, affecting the rest of the family even more adversely. However, the brutal behaviour makes sense, as it ensures that at least some individuals of the family survive to reproduce themselves.
Large tadpoles will not refrain from consuming smaller siblings.