| In contrast, both sexes of many other hoofed mammals have permanent, hollow horns. |
| Only five percent of mammals are thought to be socially monogamous, including gibbons, jackals, and tamarins. |
| They also sometimes roost in the burrows of other mammals such as hedgehogs, porcupines, and aardvarks. |
| The warm sea temperatures have led to dozens of sightings of marine mammals off the Irish coast in recent weeks. |
| Marine mammals include narwhals, beluga whales, walrus, and ringed and bearded seals. |
| Aquatic mammals that live in the waters off the coast include walrus, ringed seals, bearded seals, beluga, narwhal, and various other whales. |
