Rock Cycle - Past Life (KA)

  • Comparing dinosaurs with living animals
  • Contrasting extinct and living animals.
  • extinct
  • living
  • dead

Students sort living and extinct animals.


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 offsprings.

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.

  1. Hand out the dinosaur and wild animal placemats. Ask students the following questions.

    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 similar feet.

  2. 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 backbone. 

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