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SKULLS TELL IT ALL In this activity, students will learn about Compare characteris- BACKGROUND the above features and compare pictures tics of skulls of carni- The types of teeth an has, and the of the skulls of a (mountain vores, , and placement of its eye sockets, can indicate if lion), (deer), and omnivore omnivores. Describe the animal is a eater (herbivore), meat (.) different adaptations eater (carnivore), or of both of predators and prey and meat (omnivore.) By looking at evident in their teeth a ’s skull, we can find clues to GETTING READY and skull shape. what it may eat and whether it is a predator Make a copy of Student Handout - or prey animal. Skulls Tell It All for each student.

SCIENCE STANDARDS TEETH DOING THE ACTIVITY There are different kinds of teeth to per- CORRELATION form different functions. Incisors are in the SETTING THE STAGE SC04-S4C1-01, front of the mouth and used for SC03-S4C4-01/03 gathering. They snip vegetation or nip off 1) Have the students recall the small pieces of such as bark, nuts, seen in the Hunters and Hunted Discovery Class. Sketch the “Ani- OBJECTIVES fruit, or meat. Canines are also positioned at the front of the mouth. They are the mals and their Foods” chart (below) Students should: on the board. List the animals in the · Identify vital prey/ sharp piercing and tearing “knives” of predators and are used to kill prey. In the “Animals” column. predator body parts 2) Ask the students, “What did these and describe their sides of the mouth are premolars and molars. (In this activity for the sake of animals eat?” As they review their functions. diets, write the foods in the “Food” · Identify physical and simplicity we will only identify molars.) Molars vary in shape or size depending on column next to each animal’s name. behavioral adaptations (See chart.) of predators and prey their function. Some function like scissors for slicing meat. Others serve as grinders 3) Go through the list and have the that allow them to students classify the foods as either survive. for grinding foods like grass, leaves, and bones. All of these teeth types may be “animals” or “plants.” Write these present in different numbers from species terms in the “Food Type” column next to species, or some may not be present at to the foods of choice. Ask the students which animals only eat meat MATERIALS all. · Copy of Student or other animals. (snake, toad, and hawk) Which one eats both meat and Handout - Skulls Tell EYE SOCKETS It All for each student Eye placement varies among animals plants? (ringtail or ) · blackboard depending on the role of eyesight in their 4) Point out that some animals only eat lives. Many prey animals have eye sockets that position the eyes on the side of the VOCABULARY head. This allows for a wide range of view Canine teeth to the side and back and helps prey Carnivore animals, often herbivores, see a predator Herbivore moving in the periphery. Predators, Incisors however, generally have eyes that face Molars forward. This provides the visual acuity and Omnivore depth perception needed for a predator to pursue fleeing prey.

Teacher Information Desert Discovery Class ©2000, revised 2007 ASDM SKULLS TELL IT ALL “incisors,” have the students fill in their canines and incisors. Ask, plants. Ask the students if they can their function: To snip and collect “How do they make the meat think of an example of an animal food. Then explain that once they smaller to it?” (They that is a plant eater. (rabbit, snip their food with their incisors, use their molars.) Explain that tortoise, cow) Add this animal to they need to chew it up to be able cat molars are sharper than the list. Now explain that there are to swallow it. They use teeth deer molars, and that they words for each of these different called molars to do this. Again work like scissors to cut the kinds of eaters. Introduce the have the students compare their meat into smaller pieces. Unlike terms carnivore, omnivore, and own teeth, running their tongues deer, cats cannot move their herbivore and write them next to along their molars. Ask, “Are our jaws sideways to grind their animals, plants, or both as seen in molars flat or jagged?” (flat) molars together, so they must the chart. 5) Explain that deer molars are slice the meat into smaller 5) Explain that you are going to more jagged than ours to help chunks. Have them write the have them study drawings of the them slice and grind their food. molar function as follows: To skulls and teeth of three Then have the students fill in the cut meat. – an herbivore, omnivore, and function: To slice and grind food. carnivore – to see how they might give clues as to the kinds of foods the animals eat and whether they are predators or prey. Pass out Student Handout - Skulls Tell It All to each student. COYOTE 9) Now look at the coyote skull SKULLS TELL IT ALL MOUNTAIN LION picture. Ask, “How are a DEER 6) Next have the students look at coyote’s teeth similar to the 1) Direct the students’ attention to the mountain lion skull. Ask, “Do deer and mountain lion?” the deer skull. Ask, “Who can tell mountain lions have incisors?” ( have incisors, molars, me what a deer eats?” (Plants: (yes) “Do they have molars?” and canines.) Ask the students leaves, branches, twigs.) Ask, (yes) Ask, “Do you notice any what kinds of foods coyotes “How does it eat these foods?” (It other kind of teeth on the moun- eat? (rabbits, fruits, seeds) snips them off the plant then grinds tain lion that we have not talked Explain that coyotes eat both and slices them up.) about yet?” (canines) “What do meat and plants, so they have 2) Explain that deer have snipping you think these teeth are for?” (To teeth that help them eat both. teeth to help them tear leaves and kill prey and tear up meat.) This is especially obvious in twigs from bushes and trees. 7) Explain that cats grab their prey their molars, which are used to These are called incisors. Have with their claws and kill it with both grind and cut food. Have the students run their tongues their canine teeth. The canine teeth them fill in the function of all along the edges of their front are like a predator’s knives. See if three teeth types as follows: teeth, and point out that we have the students can find their own incisors – to snip and collect incisors, too. We have them on canine teeth. Can they feel the food; canines – to kill prey; top and on the bottom. Ask if this sharp points with their tongues? molars – To grind and cut food. is the same with the deer. (No, Have them fill in the function they only have them on the below “canine teeth” as follows: bottom.) To kill prey. 4) Write the terms “snip,” “collect,” 8) Explain that after they kill it, cats “slice,” and “grind” on the board. tear up the food in big pieces with In the space below the term Teacher Information Desert Discovery Class ©2000, revised 2007 ASDM SKULLS TELL IT ALL

EYE SOCKETS (deer) Ask the students if, from this skull shape and teeth types 10) Next have the students look at sample, they think prey animals discussed above are true for the eye sockets in the drawings of tend to be herbivores or carni- these other animals. To accentu- each animal. Ask, “Do the eyes all vores. Can they think of any other ate their findings, teachers can seem to be facing the same way on prey animals and give examples of check out the Desert Museum’s the head of each animal?” (No.) their diets? (rabbits, mice) Would Predator/Prey Desert Discov- “Which one has eye sockets that they expect the skull of these ery Kit. This interactive, hands- seem to face more to the side than animals to look more like the deer on kit contains replicas of a the others?” (the deer) Ask the or more like the mountain lion and variety of skulls, as well as students, “Why do you think this coyote? teacher information, pictures, could be?” Discuss their answers 3) Give the example of rabbits. and other museum artifacts. Kits and explain that deer are prey Rabbits have a skull more like a can be picked up at the museum animals, and they need to be able to deer, with eyes placed on the sides and checked out for a two week see all around them to watch for the of the head and incisors and period. Rate: $20/two weeks. movement of predators. molars the predominant tools for 11) Similarly discuss the skulls and snipping and grinding food. Many eye placement of the mountain lion herbivores are prey for , and coyote. Ask, “Why would a so they have a general skull ANSWER KEY mountain lion or coyote have eyes structure that reflects their and The deer has sharp slicing and pointing more forward?” (So they their need to watch out for preda- grinding molars and no canines. can focus on the prey they are tors. Remind the students that This animal eats plants and is .) Explain that forward- being a carnivore does not auto- called an herbivore. Eyes on the facing eyes, like ours, give animals matically prevent an animal from sides of its head help this prey binocular vision. This helps them being a larger carnivore’s prey. animal watch for predators. know exactly what they are seeing bats, for example, and judge distances better - skills may fall prey to a great horned The mountain lion is a meat-eater necessary for predators. Prey owl. But many prey animals are or carnivore. It has sharp, animals watch for movement to herbivores. scissor-like molars to cut meat. warn them of approaching preda- 4) From what they know of a ringtail Eyes on the front of the head tors and give them time to escape. or fox’s diets from their Discovery help this predator watch for and Class, what would the students catch its prey. COMPLETING THE HANDOUT expect the skull of a ringtail or fox 12 )With this information, have the to look like? (like that of the The coyote has strong, sharp students read the short passages coyote) canines. It also has scissor-like next to each skull and fill in the 4) Can the students think of any molars, with small, crushing blanks with the words provided. other carnivores? (bobcat, ) molars behind them. This animal Discuss the answers as a group. What would they expect the skulls eats both plants and meat and is of these animals to look like? called an omnivore. Eyes on the (more like the mountain lion) front of the head help it to see DISCUSSION and catch prey such as rabbits. 1) Review the meaning of the terms Coyotes will also collect plant herbivore, omnivore, and carnivore EXTENSION parts like mesquite beans and cactus fruit. with the students. Which animal is Have students research the skulls of an herbivore? (deer) Omnivore? additional animals and describe the (coyote) Carnivore? (mountain lion) animals’ diets. Verify if the general 2) Which animal is a prey animal?

Teacher Information Desert Discovery Class ©2000, revised 2007 ASDM