Marrow and Distance: teacher key

Bearded Vultures, grade 10 edition, written for 10th grade. Reports disagree on how high a bearded vulture drops bones and how much of its diet is bone. Scientists follow the birds with small satellite transmitters, and the birds range over very large territories.

Read the book. Print this page for the key.

Questions and answers

1. What is the pH of a bearded vulture's stomach juices?
   • 0.7 (answer)
   • 7
   • 14
2. What do bearded vultures prefer, according to the studies on bone choice?
   • Dry stones
   • Fatty bones, which have more oleic acid (answer)
   • Fresh fruit
3. Where does the Animal Diversity Web say large bones are carried before they are dropped?
   • 5 to 15 meters up
   • 20 to 70 meters up
   • 50 to 150 meters up (answer)
4. Dropping bones is inborn, but it must be practiced. What happens as a young bird grows?
   • It stops dropping bones
   • It gets better at it (answer)
   • It no longer needs rocks
5. What do the reports say about how big a bearded vulture's foraging area can be?
   • As small as a garden
   • About 7 square kilometers
   • As large as 7,500 square kilometers (answer)
6. In the text, what is marrow?
   • A kind of rock
   • The most nutritious part of a bone-based diet (answer)
   • A kind of feather

Words

• marrow: soft bone center
• ossuaries: bone-dropping sites
• oleic: type of acid
• foraging: searching for food
• territories: guarded home areas