Why Animals Cooperate: teacher key

Animal Families, grade 12 edition, written for 12th grade and up. Scientists argue over why animals help raise young that are not their own. Birds, wolves, meerkats, bats and orcas show what kin, benefits and long studies can and cannot explain.

Read the book. Print this page for the key.

Questions and answers

1. What is delayed dispersal?
   • Young leave early
   • Adults move often
   • Young stay with their parents instead of leaving (answer)
2. What does the review of cooperatively breeding birds say about non-relatives?
   • 77 percent of obligate species nest in groups that regularly include them (answer)
   • None nest with them
   • Only wolves do
3. What would the vampire bat study suggest about sharing?
   • Only relatives share
   • Generous bats were fed more when they failed to find food (answer)
   • Sharing is rare
4. What do scientists think about grandmother orcas?
   • They leave the pod
   • They never help
   • They may have evolved to live past breeding years to help raise grandcalves (answer)
5. What did the 2016 study find about Asian elephant families?
   • They are less cohesive and seem to lack a clear matriarch (answer)
   • They are larger
   • They have silverbacks
6. What does eusocial mean in this book?
   • Solitary
   • Fully cooperative (answer)
   • Nighttime

Words

• eusocial: fully cooperative
• dispersal: moving away
• generations: family age groups
• subordinate: lower-ranking
• apprenticeship: learning from experts
• cohesive: sticking together