Greater Glider

The greater glider (Petauroides volans) is a small gliding marsupial found in Australia. It is not closely related to the Petaurus group of gliding marsupials but instead to the lemur-like ringtail possum (Hemibelideus lemuroides), with which it shares the subfamily Hemibelideinae. The greater glider is nocturnal and is a solitary herbivore feeding almost exclusively on Eucalyptus leaves and buds. Like its relative the lemur-like ringtail, the greater glider is found in two forms: a sooty brown form, or a grey-to-white form. The greater glider is found in eucalypt forest from Mossman, Queensland, to Daylesford, Victoria. Greater gliders have a head and body about 39 to 43 centimetres (15 to 17 in) long, with the females being generally larger than the males. Their body is covered with a shaggy coat of fur that increases their apparent size, and the tail is long and bushy, ranging from 44 to 53 centimetres (17 to 21 in). The head is short, but with a pointed muzzle, and large ears fringed and backed with long fur. Each side of the body bears membranes stretching between the elbow and the ankle, that give the animal the ability to perform controlled glides. This is in contrast to other gliding marsupials (such as the sugar glider) that have gliding membranes stretching from the wrists to the ankles. The feet have strongly recurved claws to grip onto bark or other surfaces. There are five toes on each foot, with the first toe on the hind foot, and the first two toes on the fore foot, being opposable. The fur is soft and up to 60 millimetres (2.4 in) long; the colour is variable within the same populations, ranging from white to brown and charcoal. Body mass varies clinally from about 1,600 grams (3.5 lb) in southern Victoria to about 600 grams (1.3 lb) in north Queensland. Heat management in the greater glider is performed by licking extremities and the ventral body surface, with direct evaporation being the main method of the cooling. Furthermore, the glider can use its gliding membranes to reduce heat loss by increasing the layer of insulation at the skin surface. However, the greater glider is not well equipped to handle high ambient temperatures, as it inefficiently uses water for evaporation via salivation even though arboreal habitats are often limited in water accessibility.

Sea Otter

This aquatic member of the weasel family is found along the coasts of the Pacific Ocean in North America and Asia. The sea otter spends most of its time in the water but, in some locations, comes ashore to sleep or rest. Sea otters have webbed feet, water-repellent fur to keep them dry and warm, and nostrils and ears that close in the water. Sea otters often float at the water's surface, lying on their backs in a posture of serene repose. They sleep this way, often gathered in groups. Otters sometimes float in forests of kelp, or giant seaweed, in which they entangle themselves to provide anchorage in the swirling sea. These aquatic otters do more than sleep while floating on their backs. They are often seen with a clam or mussel and a rock that has been deftly snared from the ocean floor. Otters will place the rock on their chests, and repeatedly smash the shellfish against it until it breaks open to reveal the tasty meal inside. They also dine on such aquatic creatures as sea urchins, crabs, squid, octopuses, and fish. Sea otters are the only otters to give birth in the water. Mothers nurture their young while floating on their backs. They hold infants on their chests to nurse them, and quickly teach them to swim and hunt. Sea otters are meticulously clean. After eating, they wash themselves in the ocean, cleaning their coat with their teeth and paws. They have good reason to take care of their coats—it helps them to remain waterproof and insulated against the cold. Sea otters have thick underfur that traps air to form an insulating layer against the chilly waters (they have no insulating fat). This coat is invaluable to otters, but it has worth to some humans as well.