We are all alike to bats, donkeys, giraffes, and whales because of four things that all mammals have. These traits separate is from birds, fish, and

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2 We are all alike to bats, donkeys, giraffes, and whales because of four things that all mammals have. These traits separate is from birds, fish, and insects. Some common characteristics are the possession of fur, can breath air with a diaphragm, mammary glands in the females to feed their young and care for them until they are grown, are endothermic, have specialized teeth (large ones are called incisors), can reproduce sexually, and have large brains. The first mammals were called therapsids and appeared in the fossil record 225 million years ago. They were alike to reptiles. They were endotherms so they were able to keep their body temperatures warm so they could hunt at night. This helped to avoid the dinosaurs. Most mammals are placental mammals. This means the embryos develop in the mother s body. They grow in the uterus and a placenta is attached to the embryo and it carries food and oxygen to it. The gestation period is the time when the embryo develops in the mother. Live Young Also, all mammals, except for monotreme ones, give birth to live young. Since mothers give their young milk, they produce relationships in which the mother teaches the young the important skills they ll need to know to survive. Classifications The six largest classifications in this order rodents guinea pigs, porcupines, and chinchillas that all have one set of incisors in their upper jaw and if these wear down they will grow back because their incisors grow constantly, flying mammals with bats, insectivores with moles and cannot be found in Australia or Antarctica, primates with apes, hooved mammals like a hippo or a camel who s hump is a lump of fat that gives it energy when food is scarce, carnivores with carnivores like a jaguar. Us humans are part of the Primate class. There were also toothless mammals like anteaters, armadillos, and sloths but only the anteater is really toothless, and with their own group there is the rabbits, hares, and pikas who have two incisors in their upper jaws. Rabbits have long ears because it helps them keep cool and help it hear well. There are trunk nosed mammals made up of elephants, cetaceans made up dolphins, whales, and porpoises and they live in the water. The smallest group of mammals that live in the water is made up of manatees and dugongs.

3 Carnivores The main difference between a carnivore and a herbivore is that a carnivore just eats other animals and not plants. A carnivore s teeth are very sharp and edgy to help tear up animal flesh. A carnivore s jaws also move in an up and down motion with minimal sideways movement to help rip and tear flesh and then swallowing it whole. A carnivore will have large paws and claws that will help them hunt, chase and trap his prey. Those are tools meant to kill. A carnivore s mind is also set for hunting and killing. If a predator sees another small animal, it will think to have its next meal rather than be compassionate. A carnivore is a natural hunter. It must hunt for food so it can stay alive. Some examples of a carnivore are a lion and a wolf. Herbivores The main difference between a herbivore and a carnivore is that herbivores only eat plants rather than other animals. Herbivores have more flat edged teeth for biting, crushing, and grinding. A herbivore s saliva has digestive enzymes unlike carnivores who don t. A herbivores paws and feet are only used for mobility. They also help pick things off trees. Some examples of herbivores are a cow and a pig. Omnivores The main thing that makes us omnivores different from carnivores and herbivores is that we eat both plants and other animals. Most omnivores have teeth like carnivores but some have flat ones like herbivores. Humans are not able to sheer food but have a good side to side and back to front motion for chewing food. Many omnivores are also not natural hunters. Some examples of omnivores are humans and bears.

4 Family Groups Living together in communal or family groups is an important adaptation. Animals benefit from spending time with other members of the same species. They can help each other find food, defend against predators and care for their young. Many species live in herds, or colonies. Hibernation Hibernation is a great way to escape the cold and is a great method of surviving in harsh conditions or when resources are scarce. A lot of animals hibernate, including chipmunks, bats, and bears. Some animals, such as the America black bear, snooze through winter but can be awoken from their slumber somewhat easily. Water Conservation For animals that live in areas with little rainfall, animals like camels in the desert have to conserve food and water. They conserve fat and their humps. This can be converted into food and water. Camels also have ability to not sweat until their body temperature reaches 105 degrees Fahrenheit. Hair To many mammals, hair offers important protection from the elements. The musk ox is a great example. It has an important adaptation to its very cold home on the Alaskan tundra. Its thick, shaggy hair hangs down to the ground and gives the ox the protection it needs to endure very cold temperatures. Learn more about animal adaptations on this website! Click here

5 A monotreme is a mammal that lays eggs. There is three types of monotremes. Two of the types are echidnas and the third type is the platypus. Female monotremes lay eggs with leathery and thick shells. The mother uses her body s energy to keep her eggs warm. Baby monotremes still drink milk. Monotremes don't have nipples so babies lick milk from around the mom s mammary glands. Mammal Traits : Mammary glands Hair Diaphragm Constant body temperature Echidnas They are about the size of a house cat. They have large claws and a long snout. These traits help them dig ants and termites out of insect nests. The long-beaked echidna lives in New Guinea. The short-beaked echidna lives in Australia and New Guinea. Platypus Only one species of platypus live today. This animal lives in Australia. The platypus swims and feeds in rivers and ponds. It has a flat tail and webbed feet to help The platypus digs tunnels in river banks and lays eggs in it.

6 Like all mammals, marsupials have mammary glands, hair, and specialized teeth. Unlike other mammals, marsupials have pouches that help care for there young and unlike monotremes, they give birth to live young. Newborn marsupial development is very unique because they spend it their mother s pouch. They stay in the pouch for many months. There are over 280 species of known marsupials and most of them live in Australia, New Guinea, and South America. The Pouch Marsupials are born at a very early stage of development and it usually born after just days or weeks after fertilization. Newborn kangaroos are about the size of a bumblebee. Newborn marsupials are hairless and only have their front legs well developed to drag themselves through the hair in their mother s pouch on her belly. The newborn climbs in, latches onto a nipple, and then drinks the milk. Kinds of Marsupials Some common marsupials include kangaroos, koalas, and the only marsupial native to the U.S., the opossum. Some unfamiliar marsupials are wallabies, bettongs, and numbats. Most marsupials live in and around Australia. A marsupial that eats other animals is the Tasmanian devil and it lives in Tasmania. Koalas only eat eucalyptus leaves. Endangered Marsupials The population of marsupials in the world is decreasing. At least 22 of Australia s native marsupials have gone extinct in the past 400 years. There are also many who are now endangered. When Europeans brought animals to Australia in the 18th and 19th centuries, the marsupials had to compete for food and had to avoid the predators. Habitat destruction is also a threat towards marsupials. The Tasmanian tiger was hunted and have probably gone extinct because it hasn t been seen since Today, conservation efforts across Australia are helping to protect the unique marsupials that live there. An example of one is here.

7 Two different groups of aquatic mammals are Cetaceans and manatees and dugongs. Cetaceans Cetaceans include dolphins, whales, and porpoises. All cetaceans live in water. At first glance many cetaceans may look like fish but they are mammals. Unlike fish though, they have lungs, give birth to live young, and nurse their young. To keep warm, many mammals that live in cold water have a kind of fat called blubber that keeps their body warm. Most of the largest whales are toothless. The strain tiny, shrimplike animals from the sea water. Although dolphins, porpoises, sperm whales, and killer whales all have teeth to help them eat. These animals also use echo location, like bats, to find fish and other animals. Manatees and Dugongs The smallest group of mammals that live in the water are the manatees and dugongs. Another name for a manatee is a sea cow. This group includes three species of manatee and the dugong. Manatees and dugongs use their front flippers and tail to swim slowly through the water. Manatees and dugongs live along ocean coasts and in rivers. They are large animals that eat mostly seaweed and water plants. These animals spend all of their time underwater, but they occasionally lift their noses from the water to breathe air.

8 Primates Scientists classify prosimians, monkeys, apes, and humans as primates Hands These animals have five fingers on each hand and five toes on each foot. Most have flat fingernails instead of claws. Brain Primates have larger brains than most other mammals the same size have. They are considered highly intelligent mammals. Body Primates have unique arrangements of body parts that help do complicated things. All primates have forward facing eyes that can focus on a single point. Primates also have opposable thumbs that allow them to grab and hold things. Habitat Primates usually live in trees. They climb with their grasping hands and feet. Their flexible shoulder joints allow them to swing between branches. Diet Primates usually eat leaves and fruits, and some primates even hunt other animals. Kinds of Primates There are many different kinds of primates. One example are the orangutan that can walk upright and has a larger brain and body than other monkeys. Another one is the spider monkey that uses its grasping tail to move along the trees. We are part of the primate group, too! Learn more about primates here!

9 Armadillo: A toothless animal that rolls up in a ball if it feels threatened and are protected by tough plates. Bats: Flying mammals that are only active at night and use echolocation. Carnivore: Mammals that have large canine teeth and special molar teeth for slicing meat. Cetaceans: A group of mammals made up of whales, dolphins, and porpoises. Flying mammals: A group that only contains bats because they are the only mammals that fly. Bats are only active at night. Gestation Period: The time in which an embryo develops within the mother. Guinea Pig: In the rodents group, alike to squirrels, mice, rats, porcupines, and chinchillas. Hippopotamus: Are hoofed mammals that mostly live and breed in water. Hoofed mammals: A group with animals that have thick hoofs and include two orders odd toed and even toed. Includes horses, pigs, and hippos. Humpback whale: In the cetacean group, have no teeth so they strain sea water for small shrimp like creatures. Hyena: In the carnivore group, live in Africa. Indian Elephant: One of the only living animals that have a trunk and are in the trunk-nosed mammal group. Insectivore: A group of mammals that just eat insects and include moles, shrews, and hedgehogs. Jack Rabbit: Part of the rabbits, hares, pikas group. Large ears help it hear well and keep it cool. Also work with a sensitive nose and large eyes to sense predators. Manatees and Dugongs: The smallest group of mammals that live in the water. Marsupial: A mammal that carries and nourishes its young in a pouch. Monotreme: A mammal that lays eggs. Placenta: An organ that attaches the embryos to the uterus. It caries food and oxygen from the mother s blood to the embryo and carries wastes away from the embryo. Primates: A highly intelligent group of mammals that includes prosimians, monkeys, apes, and humans. Rabbits, Hares, Pikas: A group of mammals that are similar to rodents but have two sets of incisor teeth and have shorter tails. Rodents: Group made up of squirrels, mice, rats, guinea pigs, porcupines, and chinchillas that makes up more than one third the mammal species, found in every continent except for Antarctica, and have one set of incisor teeth. Sea Cows: Another name for a manatee which is part of the manatees and dugongs mammal group. Shrew: Part of the insectivore group and has a small brain. Spider Monkey: Uses grasping tail, long arms, and long legs to move along the trees. Toothless Mammals : Includes anteaters, armadillos, and sloths but only the anteater is really toothless. Trunk-Nosed Mammals: Includes the elephant which is the only living animal with a trunk. Uterus: The organ where the embryo grows in the mother s body.