Evidence From the Soil: teacher key

Bugs That Clean Up, grade 11 edition, written for 11th grade. Termite guts, drought tests, tea bags and tracer nitrogen are some of the ways scientists have studied decay. Their results overturned old ideas about termites and show how much about ants, beetles and soil animals is still unknown.

Read the book. Print this page for the key.

Questions and answers

1. What did Purdue and Florida researchers find when they fed termite colonies wood or paper?
   • The gut bacteria changed a lot with diet
   • The gut bacteria did not change with diet, while termite and protist gene activity did (answer)
   • The termites stopped eating paper
2. How do young termites get the microbes that help them digest wood?
   • From the soil only
   • From the queen's eggs
   • Nest mates pass gut contents to them (answer)
3. Which animals are more closely related to pill bugs?
   • Crabs and shrimp (answer)
   • Beetles
   • Springtails
4. What can be concluded from the wood-stake experiment about decay in tropical forests?
   • Climate alone predicts how fast wood decays
   • Living animals may predict wood decay better than climate (answer)
   • Moisture has no effect on wood decay
5. What can black soldier fly larvae do in manure?
   • Raise the number of fecal bacteria
   • Turn the manure into wood
   • Cut fecal bacteria and other contaminants (answer)
6. What is comminution?
   • Fragmenting leaf litter into pieces (answer)
   • Storing dung underground
   • Moving from one nest to another

Words

• trophallaxis: food sharing
• eusocial: fully social
• comminution: breaking into pieces
• symbionts: partner microbes
• litterbags: leaf mesh bags