Extinct organisms are once-living organisms of the Earth that have
vanished and can never live again. Dinosaurs once lived on this planet, but
they are now extinct. Living organisms eat, grow, and reproduce in today's
world. Living organisms can become extinct, if they all die and leave no
The word "dinosaur" refers to the dominant land animals that
lived between 225 million years and 65 million years ago. Although your
students will not be able to understand the magnitude of that time span,
emphasize that dinosaurs have been extinct for a long, long time.
Paleontologists (scientists who study ancient life and fossils) have
grouped "dinosaurs" into two large groups: Saurischians
(lizard-hipped) and Ornithischians (bird-like hipped). Animals like
sabertooth cats, mastodons, and mammoths were not dinosaurs. They are
usually referred to as prehistoric mammals. These animals lived in
pre-civilization times with our ancestors, but not with the dinosaurs. Both
groups, however, are extinct, but dinosaurs have been extinct much longer
than prehistoric animals. The activity below stresses the difference between
dinosaurs and prehistoric animals (both of which are extinct) and organisms
that are living today.
- Hand out the dinosaur and wild animal placemats. Ask students the
Which of the wild animals is a mammal (all on the wild animal
placemat except the ostrich and penguin are mammals)?
Which of the mammals on the placemat lives in water (the whale and
seal live in water)?
Which placemat shows extinct animals and which shows living animals?
You may want to have the students look at the placemats for
similarities. For instance, some students may see the kangaroo and Tyrannosaurus
rex as similar because of their small forearms. The Apatosaurus
and the elephant may look similar because they are both big and have
- The kit includes 4 bags labeled extinct
(prehistoric); extinct (dinosaurs), living (vertebrates) and living
(invertebrates). Reinforce the words by having the students
compare the different groups. You may want to spend time on the
difference between the groups. First have them group extinct versus
living. The "Extinct" group should emphasize
prehistoric versus dinosaurs. The "Living" group should
emphasize those animals with a backbone and those without a