Have difficulty maintaining body temperature on rainy days.Regulate body temperature by moving about canopy - seeking shade or sun.Fur provides insulation to protect against cooling.Echidna has lowest body temperature of 28-29☌ (82.4 - 84.2☏). Unlike most mammals - body temperature varies with temperature of environment and is lower than most mammals 33-36 ☌ (91.4 - 96.8☏).Olfactory bulbs extremely well-developed.Four-chambered stomach is filled with bacteria, which helps ferment the plant matter consumed.Unlike other mammals, organ including the stomach, spleen and liver are located in different areas, due to upside-down lifestyle.Blink frequently and slowly - often one eye at a time.Convex cornea and thick lens means poor discrimination - Rely little on vision to carry out normal patterns of behavior (Mendel).Rely on other senses to obtain food and make contact with other sloths. No ciliary muscles means near-vision is poor - most are myopic.Distribution of photoreceptors indicates adaptation to night vision.Eyes very mobile - can be partly retracted when eyelids are closed.Small external ears, close to the head, imbedded in fur.Teeth grow throughout lifetime and have a cupped grinding surface.They are sharpened by rubbing against lower teeth. (Although they look like canines, they are actually derived from other teeth). Two large, blade like teeth in front for biting.5 simple, peg-like teeth on each side in upper jaw.Three-toed sloths may have quite small or absent canine-like upper teeth.Nearly all other mammals have 7 neck vertebrae.Three-toed sloths have 8-9 neck vertebrae and can rotate heads 270 degrees. Two-toed sloths possess 6-9 neck vertebrae and can rotate heads 90 degrees.Extreme mobility of limbs allows support for the body in many positions.A wide range of movement possible in several directions from the wrist and between-wrist joints.Claws are mounted on tips of 2nd and 3rd fingers, which together form the "hook".Modification of hands and feet into rigid hooks - the 2 digits on each forefoot are closely bound with skin their entire length. Elongated limbs and trunk are adaptations to acrobatic, hanging lifestyle.26, in the exact same location, but 10 feet deeper, and is believed to have lived 600,000 years ago.Īll three animals date from the Pleistocene Period - the Ice Age. The California Gray whale skeleton was found on Feb. The 500,000 year old Columbian Mammoth remains (skull, tusks and several foot bones) were found at the site on Feb. In case you are keeping score on the construction site finds: Jefferson, thought of as the father of modern paleontology, had a strong interest in the fossils of huge creatures such as mammoths and giant sloths. It is not known if the find is a Megalonyx jeffersonii. Ironically there is a species of giant ground sloth that is named after the law school's namesake, Thomas Jefferson: Megalonyx jeffersonii. Paleontologist Pat Sena of the San Diego Natural History Museum, who found the sloth bones, said the bones are poorly preserved. The sloth bones were found at about the same depth as the whale bones, indicating the sloth lived about 600,000 years ago. The bones – part of a vertebra, as well as tooth and skull fragments – were unearthed Friday in a different part of the site from where whale and mammoth bones were found last month. But the bones are in poor shape and may not be salvageable. More prehistoric bones – this time, those of a giant sloth – have been found at the East Village construction site of the Thomas Jefferson School of Law, the school said yesterday. Another mammoth's bones get new digs(2/5/09).
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