The world of animals is no doubt interesting, but then there are some things about certain animal species that go well beyond interesting ... into the realm of unusual. These things usually revolve around their physical characteristics and behavior. Did you, for instance, know that the liver of polar bears is extremely poisonous, as it contains too much of Vitamin A? More of such facts are given below. Unusual Facts About Animals ✦ A female anaconda is 3 - 5 times bigger than an average male anaconda. ✦ A lion can mate 50 times a day. ✦ Cats can sleep for up to 16 hours a day. ✦ Mockingbirds can imitate sounds of other birds. ✦ The rat tops the list of animals that can live without water for a long time. The camel comes second. ✦ The eyes of donkeys are placed in such a way that they can see all four feet at the same time. ✦ There are around 2,600 known species of frogs. These amphibians are found on every continent of the world, except Antarctica. ✦ The venom of a poison arrow frog can kill approximately 2,200 people. ✦ Crocodiles can swallow large stones that stay permanently in their bellies and are used as ballast in diving. ✦ Slugs have four noses, but none of them are visible. ✦ An electric eel can deliver a shock of up to 650 volts. It's a defense mechanism that it uses to defend itself from predators. ✦ A porcupine has 30,000 quills on an average. Its average heartbeat is around 190 beats per minute, which reduces to 20 during hibernation. ✦ Butterflies surprisingly use their feet to taste. ✦ A cockroach can stay alive for up to nine days without its head, before it dies of hunger. ✦ A woodpecker can peck up to 20 times in a second. ✦ Bats unmistakably turn left when exiting a cave. A brown bat can catch around 1,200 mosquito-sized insects in an hour. ✦ The call of a blue whale reaches up to 188 decibels. It can be heard over hundreds of miles underwater, thus entitling it to be the loudest animal on Earth. In loudness, the whale is followed by the howler monkey. ✦ The hummingbird can hover and fly straight up, down, or backward. ✦ Father catfish keep eggs in their mouth until they are ready to hatch. During this period, which may span several weeks, they do not eat. ✦ A chameleon can move its eyes in two separate directions at the same time. ✦ A cow can be led upstairs, but it can't be brought downstairs. ✦ A dolphin consumes food equivalent to one-third of its weight every day. ✦ On an average, the sloth travels roughly about 15 feet a day. ✦ Generally, an average male llama weighs up to 375 lb and stands 5 - 6 feet tall. ✦ A newborn kangaroo is as small as a coffee bean. ✦ Generally, 95 percent of a panda's diet consists of bamboo. ✦ A full-grown bull's average weight is 900 lb. ✦ One of every five thousand North Atlantic lobsters is born bright blue in color. ✦ The Black Uakari Monkey travels around 1½ to 2 miles every day on an average. ✦ A female ferret will literally die, if she can't find a mate after going into heat. ✦ A female praying mantis may eat the male's head just after or even during mating. ✦ The humpback whale has the longest flippers among marine mammals, measuring up to one-third of its body length.