There are over 5000 species of mammals on Earth. The platypus has two ovaries but only among the two is practical i.e. the left one. An elephant’s toes can weigh more than five tons so they have large heavy feet. But they have big, soft, spongy feet that spread their weight out so well they barely even leave footprints. The sweat glands of a tree squirrel are situated on their feet. Mammals have the ability to maintain a constant body temperature naturally, irrespective of the temperature of the environment. A normal body temperature of mammals ranges from 90-104F.
The lower jaw in mammals is made from a single bone. Gray squirrels are considered to be living fossils. The reason for this is they haven’t changed much in 37 million years. Shrews have so little body fat they cannot go over a couple of hours without food. They will die if they skip a meal. The gerbil rubs its abdomen on cage accessories to mark his territory. Humans also fall in the class of mammals. The middle ear of mammals comprises 3 bones. A polar bear’s skin is black under its hair that look white but in fact are colorless and hollow. Sugar gliders have the ability to glide over 150 feet. Golden hamsters are also known as”Syrian” hamsters, since they originated in Syria. A female hippopotamus give birth and breastfeed under water – even though almost all their predators reside in the water.