Examples of herbivorous animals: rabbits, deer and beaver

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1 Mammal Adaptations Mammals are a group of animals that fit together because they all 1)have fur or hair 2) bear live young 3) feed their young with milk from specialized mammary glands. We are going to look at some adaptations of some mammals. Hair: Hair is what helps protect the animals from the environment. It helps to keep the animal warm in the winter. There is a soft underhair (pelage) that helps to insulate the animals and a coarser, longer guard hair to protect the animal and provide coloration. The density and coarseness of the hair is a clue to the type of environment the animal must survive in. The coloration of the hair is also often an adaptation that allows the animal to hide or send a message to other animals to "stayaway't! Teeth: The size and shape of an animal's teeth give us clues into what the animal eats. Animals can be grouped into 3 categories based upon what they eat: Carnivores: These animals eat mainly meat (other animals). Because of this, two types of teeth are found in these animals. o Canines: long, sharp teeth to grasp and kill prey o Cheek-teeth: more blade-like to cut and chew Examples of carnivorous animals: African lion, weasels and Bobcats Omnivores: These animals eat both meat and vegetables. The teeth are adapted so that these animals can eat meat and grind and chew plant material. o Canines: Blunter than found in carnivores o Cheek-teeth: flatter for grinding plant material Examples of omnivorous animals: humans, raccoons, skunks and squirrels Herbivores: These animals eat mostly plant material. Since plants usually are fibrous, the teeth of these animals must be adapted for side-to side movement. o Canines: Many herbivores do not have canine teeth. If they do, they are small and blunt. o Selenodont molars: These are special jaw teeth in some herbivores that have high points at an angle to the direction the jaw moves. This helps grind food. o Lophodont molars: Other herbivores have these type of jaw teeth where the high points run the same directions as the side to side movement of the jaw. 76

2 Examples of herbivorous animals: rabbits, deer and beaver -~-- Eye Placement: The location of the eyes on the head of the animal is a clue how the animal sees. An animal whose eyes are located on the sides of its head must cock its head to see things in front of it. Animals with eyes in the front must e able to turn their heads to see sideways. s? Activity: 1. Look at the pelt and the skull replica for each animal and answer the questions about each. Below is a description of the animals we are studying. Animal to What does animal here? adaptati have you not for?the special omnivore, coloration? think If orlocated? Is any carnivore, skull. Describe Where does this eyes How so, are see What think of fur conditions there protects you ma~ teeth what you the a is this kindyou How herbivore? tell? can animal how affecthe Weasel Skunk Squirrel Raccoon Bobcat 77

3 Opossum (This is NOTa mammal!) Read below to find out more! Muskrat Deer Beaver 1. How do each of these adaptations help this animal survive? 2. Do you think these animals will look exactly the same in 200 years? Why or why not? 3. Which animals seem to be the most similar? In what ways? 4. Which animals see to be the most different? In what ways?.'

4 Animal Info.: Rabbit: These animals are designed for speed! They have powerful hind legs that propel them as they hop along quickly. They have a very keen sense of hearing (what adaptation would allow this?) and like to dig burrows underground where they live. They are herbivores eating grass, leaves and bark. Rabbits belona to a group called rodents. Raccoon: Raccoons look like bandits with black masks of fur! They also have black rings of fur on their tails. They can use their clawed fingers to grasp food and scavenge food out of garbage cans. Often they eat fish or other water animals. They are omnivores. Weasel: These slender animals are found all over the globe. Often the tip of their tail is black. When they move the black tip on their tale, predators will sometimes chase the tip of their tale and miss catching them! This helps them survive becoming someone else's lunch. Weasels are carnivores. 79

5 Bobcat: Bobcats are carnivorous hunters. They have strong jaws that can grasp prey and sharp, retractable claws. The coat of the Bobcat is spotted, why? It has large ears but a short, stubby tail. Many Bobcats have tufts of hair on their ears to help them hear better. Skunk: Skunks produce an awful spray that smell terrible! This oily, yellow liquid can be sprayed at predators to keep them away! Unfortunately, skunks often spray their liquid when they are frightened by humans. Skunks eat insects, plants and other small animals. They are considered to be omnivores. They usually hunt at night making them nocturnal. The coloration of the skunk helps to warn other animals that danger is near (smelly danger that is). Squirrel: Squirrels are very common in Kentucky. They are very agile, climbing trees and walking on telephone lines. They have large, bushy tails and strong hind legs. They are considered to be rodents. They eat nuts, seeds, leaves, bulbs and roots. They are considered to be omnivores.,,----,.. 80

6 Opossum: The opossum is NOT a mammal! Although it has fur, it carries its young in a pouch, like a kangaroo! This makes it a marsupial. Opossums are also nocturnal. They eat insects, seeds and other small animals. They are omnivores. They have a hairless tail that is able to grasp and hold onto objects. Muskrat: The muskrat is also a rodent. It is an omnivore that eats water plants and shellfish. Muskrats are usually found in or near water. They are very good swimmers. They have special glands that produce a strong musky smell. Deer: Deer are large animals that have powerful legs that allow them to run fast. The back of a IIwhite-tailed' deer is white so that the deer can flit its tail to warn others of danger. Deer eat plants and are considered to be herbivores. Beaver: Beaver eat pond lilies and the bark of trees (aspen and birch)and so are considered to be herbivores. They have very specialized teeth to chew through the branches of trees. The four front teeth are called incisors. The lower incisors never stop growing but are kept short by constant gnawing. Beavers sometimes IIdamll rivers because they chew down trees that stop the flow of water. They have a large, broad, paddle-like tail that helps them to swim. 81