Why do rabbits have particularly long ears?

Rabbits have the longest ears among animals. In Europe, there is a fable that “the rabbit’s ears were stretched out by people pulling on them.” There is also a legend that “it gave its canine teeth to another animal and received a pair of large ears in return, which is why its ears are particularly large.” According to Japanese folklore, “rabbits grew long ears from eating loquat leaves.” In reality, rabbits use their ears extensively, and only with ears as long and large as theirs can they best survive.

All animals with ears rely on them to distinguish sounds emitted by various objects. The structure of ears can be divided into three parts: outer ear, middle ear, and inner ear. The outermost part of the outer ear has a prominent protrusion called the “pinna,” which collects sound waves coming from all directions. Therefore, the larger the pinna, the clearer the sounds it picks up. If the pinna could freely turn towards the direction of the sound source, the sounds heard would be even clearer and audible from a greater distance. Compared to rabbits, humans have relatively small and inactive pinnas, lacking the ability to move them like rabbits do. However, among higher animals except humans, most can move their pinnas.

Rabbits are herbivorous animals specialized in eating grains, leaves, wild grasses, vegetables, and other plants. They have no ability to attack or harm other animals. On the contrary, they are often threatened by foxes, martens, ferrets, owls, eagles, and others, and can easily become prey if not cautious. When attacked, they cannot use horns to defend themselves, nor can they bite or release a foul odor as a weapon like some animals do. Thus, among animals, rabbits are considered the weakest and most incapable. Their only “skill” is their ability to jump and escape. Therefore, they frequently raise their ears to listen attentively from all directions, as a precaution. It is in this environment where enemies surround them that rabbits naturally developed their notably large ears.