There are more than 5,000 species of mammals on Earth. The platypus has two ovaries but only one of the two is functional, that is, the left one. An elephant’s feet can weigh more than five tons, which means they have large, heavy feet. But they have big, soft, spongy feet that distribute their weight so well that they barely leave footprints. A tree squirrel’s sweat acorns are found at his feet. Mammals are capable of maintaining a constant body temperature naturally, regardless of the temperature of their environment. The average body temperature of mammals ranges from 90-104F. A squirrel’s natural predators include the owl, fox, bobcat, hawk, raccoon, and opossum.
Did you know that a female Pacific gray whale gestates and gives birth to a 2,000-pound baby, migrates over 10,000 miles, and produces 6 tons of breast milk without eating a single bite, using only her blubber for fuel? The lower jaw of mammals is made up of a single bone. Gray squirrels are considered living fossils. The reason for this is that they haven’t changed much in 37 million years. Shrews have so little body fat that they can’t go more than a couple of hours without eating. They will die if they skip a meal. The gerbil rubs its abdomen on the cage accessories to mark its territory. Humans also fall into the category of mammals. The middle ear of mammals contains 3 bones. A polar bear’s fur is black under its fur that appears white but is actually colorless and hollow. Sugar gliders can glide over 150 feet. Golden hamsters are also called “Syrian” hamsters, because they originated in Syria. A female hippopotamus gives birth and nurses underwater, although almost all of her predators live in water.
