- Male walruses with the largest tusks usually dominate in the social group. The tusks of males are slightly longer and thicker than those of females and are used for fights.
- Walrus tusks mainly serve a social purpose, as they are used in establishing hierarchical relationships and demonstrating threats. Observations of tusk and vibrissae wear show that walruses dig the ground not with tusks, but with the upper edge of the snout.
- A walrus may have between 400 and 700 vibrissae on its upper lip, arranged in 13–18 rows. Their number reaches a maximum in adult individuals.
- A walrus has paired air sacs, which inflate under the skin of the neck and allow it to swim vertically while sleeping. The sacs are formed by the bulging of the upper part of the esophagus and have no closing valves.
- Walruses have a thick layer of fat reaching 15 cm. The thickness of the skin on the neck and shoulders of males can be up to 10 cm.
表型海象
在这里我们介绍海象的外貌，以及毛色如何随年龄变化。
海象：它是怎样的