Dino debate: predator or scavenger? (Chart Reading/Critical Thinking).

Scientists agree: Tyrannosaurus rex was a meat-eater, or carnivore. But they hotly debate how T. rex got its food. Was it a ferocious hunter? Or did it scavenge dead and rotting animal carcasses? The table below presents some opposing theories. Study the evidence, then conduct research in an encyclopedia or online reference source to answer the questions below.

Argument for T. rex as           Argument for T. rex as Predator
Scavenge

Good eyesight for spotting       Large visual lobes in brain.
carcasses miles away.            Forward-facing eyes mean it had good
                                 depth perception, useful in hunting.
Huge olfactory bulbs (part       Huge olfactory bulbs for tracking
Of brain used for smell)         prey.
for finding rotting animals.
Arms too small to grab prey.     Predators like snakes, sharks, and
                                 hawks hunt expertly with no arms!
Huge legs built for covering     Could probably run faster than the
long distances--but not built    plant-eating dinos it fed on.
for speed.
Had 50 to 60 long, serrated      Banana-shape teeth for chomping
teeth. But as cutting blades,    Through flesh and bone. Regrew
they weren't very efficient.     broken teeth regularly throughout
                                 life.
Too large, heavy, and clumsy     Tail provided balance during quick
to Wrestle around with prey.     turns.

Use complete sentences and explain your reasoning. Support your answers by referring to traits of modern predators like alligators and modern scavengers like vultures.

1. Which type of animal--predator or scavenger--would need keener senses of sight, smell, and hearing? Why?

2. Do you think scavengers or predators need stronger jaws? Why?

3. Which type of animal would need the ability to scare away other animals?

4. Which kind of animal would need the ability to sneak up on animals?

5. Do you think T. rex was a scavenger, predator, or both? Why?

6. What kind of evidence do scientists need to resolve their debate?

DON'T STOP NOW:

For a long time, spotted hyenas were considered scavengers. Now evidence shows that in addition to scavenging, hyenas actually hunt and kill much of their food. What does this suggest about carnivores?