Tests, Estimates and Old Arguments: teacher key

Fossils, grade 10 edition, written for 10th grade. Georges Cuvier tested whether extinction was real, and Mary Anning's find met doubt. Read how estimates of speed, whale chemistry and ancient reefs show what fossils can and cannot say.

Read the book. Print this page for the key.

Questions and answers

1. How did Georges Cuvier test whether extinction was real?
   • By digging in Arctic ice
   • By counting tracks
   • By comparing living and fossil animals part by part (answer)
2. How is footprint speed estimated?
   • By dividing stride length by hip height (answer)
   • By weighing the fossil
   • By counting the toes
3. A bone records what an animal drank because salt water and fresh water carry different what?
   • Ray bones
   • Oxygen isotopes (answer)
   • Sedimentary layers
4. A two-legged dinosaur left a footprint 0.5 meters long. Using the pages, about how high were its hips?
   • About 0.5 meters
   • About 4 meters
   • About 2 meters (answer)
5. As of November 2026, where do the oldest known fossils, about 3.5 billion years old, come from?
   • Tiny living things in the sea in Australia (answer)
   • Dinosaur eggs in Canada
   • Whales in estuaries

Words

• anatomy: body structure
• isotopes: element forms
• estuaries: river mouths
• stromatolites: layered reef rock
• cyanobacteria: tiny living things