众所周知，在南极没有北极熊。那么在南极的生态圈中，豹海豹就充当了北极熊的角色，成为众多企鹅的噩梦。 豹海豹（Hydrurga leptonyx）是南极第二 ...

At first glance, this leopard seal (Hydrurga leptonyx) might seem like it’s having the time of its life—mouth wide open in what looks like a hearty laugh. But don’t be fooled by its ...