A Bear Family Tree and a Winter Sleep: teacher key

Black Bears, grade 10 edition, written for 10th grade. Black bears have a long family history, a recovery in the 20th century, and a winter dormancy that scientists measure. Here is what the counts and the studies show.

Read the book. Print this page for the key.

Questions and answers

1. About how long ago did the bear family evolve from a common ancestor?
   • 4 to 7 thousand years ago
   • 4 to 7 million years ago (answer)
   • 4 to 7 days ago
2. What did the lead scientist of a California study call hair snares?
   • A trap for cubs
   • A weak method
   • The gold standard for counting American black bears (answer)
3. In the Alaska study, how far did the bears' heart rate slow?
   • From about 55 to about 14 beats a minute (answer)
   • From 14 to 55
   • It did not change
4. A male black bear's home range is usually 3 to 8 times larger than a female's. Which bear likely covers more ground?
   • The female
   • They cover the same
   • The male (answer)
5. What happens to a black bear's heart rate in winter dormancy, according to the International Association for Bear Research and Management?
   • It speeds up to 200
   • It slows to 8 to 19 beats per minute (answer)
   • It stops

Words

• dormancy: winter rest
• metabolism: body's energy use
• snare: hair trap
• subspecies: kind within species