Dinosaurs - Lesson 5: Meat and Plant Eaters

On this page
- Encountering the Idea
- Exploring the Idea
- Getting the Idea
- Organizing the Idea
- Applying the Idea
- Closure and Assessment
- List of Activities for this Lesson

BIG IDEAS: Dinosaurs existed by eating large quantities of plants like ferns or by eating other animals. We can classify dinosaurs in many different ways.

Whole Group Activities

• Illustrations of meat eating and plant eating dinosaurs (pp. 12-27 of D. Dixon's Be a Dinosaur Detective)
  
• Snack for each child: Two pieces of a hot dog or lunch meat, a lettuce leaf, carrot sticks or other raw vegetable, two pieces of fruit (apples, grapes, bananas, etc.)
  
• Paper plates, napkins, forks for the snack
  
• Chart, similar to the one in Activity - Fossil Hunting, with new headings: Name of Dinosaur, Kind of Food, How Can We Tell?
  
• A hole punch; one sheet of construction paper per student
  
• A large, hand-held mirror for the Science Center
  

Encountering the Idea

In a whole class discussion the children hypothesize about the food dinosaurs ate. The students' responses are written on a rebus chart. They talk about the differences in the characteristics of the meat-eating dinosaurs and the plant-eating dinosaurs. Show the pictures at this time. If a dinosaur was an herbivore, ate plants only, what kind of teeth did it have? Did it have claws? Did it have a large mouth or a small mouth? What if the dinosaur was a carnivore and ate meat only, what kind of teeth would it have? Would it have claws? We will discover the answers to these questions in this lesson and in the next.

Exploring the Idea

At the Science Center, the students examine their own teeth with a large, hand-held mirror to see the varying shapes and the uses of the different kinds of teeth.

• Using the hand-held mirror to see her teeth, the teacher demonstrates to the students what they are to look for when examining their teeth. Tell them that some of them may not have all of their new teeth, but since they are working in small groups, they can share the information they have about each other.
• Say: the front teeth are long, wide and flat; there are four of these. The next ones are long, round and have a point; there is only one of these longer ones on each side of my mouth. The molars are next and are round and short but are rough on the top; we have two or three of the molars on each side of our mouths.
• The same type of teeth are on my upper jaw as on my lower jaw.
• Ask the students to make other observations about their teeth: the size, number, any other characteristics they notice. They report their observations to the class.

At the Mathematics Center, the children:

1. use the counters placed in the center to count and/or sort according to color and kind of dinosaur.
2. may sort the food into meat, vegetables (or leaves) and fruit. The teacher motivates counting by asking: Which of these sets has more? Which has less? How do you know? Do you match them like this? Which set has some dinosaurs that are not matched? Is it the one that has more?
3. Which sets have the same number of dinosaurs? How do you know? Is it because when you match the sets, there are no dinosaurs left over in either set?
4. Students complete Activity - Name Matching.

Getting the Idea

We know that there were many different kinds of dinosaurs living on earth many millions of years ago. How do we know that there were many different kinds? How do we know that there was not just one kind of animal? The fossils that have been found tell us that there were many different kinds because the fossils that have been found are of different shapes, types and sizes. From this evidence paleontologists can conclude that the dinosaurs were different. We can also conclude that there were many different kinds of plants because of the different plant fossils that have been found.

Each child is given a snack and, while they eat, they count the pieces of food left on their plate. Begin a discussion of the importance of finding different types of dinosaurs' and other animals' teeth, as the students munch on "meat" and on "plants". Scientists have found fossilized teeth that tell us what these different animals ate. In the Science Center, you, yourselves, have looked at your teeth and you can see that they are different.

Each type of tooth has a special job. Some teeth are for biting. Which are those? ( The student think about which teeth they are using to eat the snack of "meat" and "plants" - the front teeth.) Since many of you are getting your new front teeth, let's describe them. The new front teeth have sharp ridges on them still. But mine (the teacher's front teeth) don't have these sharp points on them. Why do you think that is? Yes, in time the ridges wear off.

Which teeth are for tearing off pieces of meat? (The incisors, which have sharp points on them. These are for biting also.) What are the back teeth for? (For grinding and smashing into smaller pieces so that we can swallow our food.) These teeth are also called molars. In Spanish, the word moler means "to grind," which is what these teeth do to the food before we swallow.

Which teeth are we using to eat our "plants"? (We bite first, and then we chew; but we don't have to tear the fruit or vegetables.) Humans have both kinds of teeth because humans eat meat, and humans eat plants also.

What do we think if a dinosaur skull is found and all its teeth, but a few front ones, are flat? (That they were plant eaters.) What do we think if a dinosaur skull is found and all its teeth, but a few front ones, have sharp points? (That they were meat eaters.)

What do crocodiles eat? (Fish and large mammals, and they've been known to attack and eat humans.) What do lizards eat? What do turtles eat? (Many turtles are toothless; they eat mostly insects, slugs or other small animals; they can eat plants but only the soft parts, because they do not have teeth that can grind the food.)

What observations did we make that helped us guess what the dinosaurs ate? What observations do we use to say whether a dinosaur is a meat eater or a plant eater? Remember, observations help us to make good guesses. These observations helps us sort the dinosaurs in many different ways.

Organizing the Idea

At the Art Center, children make dot dinosaurs. Using a hole punch and construction paper, they cut out as many dots as they need to outline a dinosaur pattern. These patterns may be used later for a wall mural.

The students make a chart illustrating the different types of dinosaurs that they have studied and they categorize dinosaurs by what they eat - plants or meat.

Applying the Idea

Show students a picture of three or four small molars that are placed in a row, as if in a mouth. See Activity - Dinosaur Teeth. The molars are flat, broad teeth but have very sharp ridges. Ask the students what they think they can tell about the creature that was the owner of these teeth from looking at them. (If the teeth are small, the creature was small also. Since they are molars and broad and flat, and there are several, maybe the creature was a plant eater. Also, since the ridges are still sharp, maybe it was still very young.)

Closure and Assessment

Oral Interviews

1. Today we learned that some dinosaurs ate plants and others ate meat. How can we tell which dinosaurs ate meat and which ones ate plants?
2. What are some new words we learned today?
3. Pointing to dinosaur counters: Count these dinosaurs. How many yellow dinosaurs do we have? How many red? Which set has more? Which set has less? How do you know?
4. What are two different ways you can use to tell which set has more? Yes, you can match the members of the set one by one, or you can count to see which number is greater.
5. What else would you like to know about dinosaurs?

List of Activities for this Lesson

1. Dinosaur Teeth
   
2. Name Matching