Beaver (English name: beaver) is a semi-aquatic mammal belonging to the order Rodentia. They live in rivers, lakes and swamps in North America, Europe and Asia, often building dams and houses in which to roost and hunt.The beaver's body is well adapted to aquatic life, with well-developed swimmi...
As we all know, animals on land need to sleep, although their sleeping postures and methods are different. So, do animals in the ocean also sleep? The answer is yes, they also sleep, and their sleeping postures and methods are even more special. In fact, sleep is just a s...