Safety in Numbers: teacher key

Red-Bellied Piranhas, grade 7 edition, written for 7th grade. Red-bellied piranhas swim in shoals, and a shoal is more about safety than hunting. Meet a river fish with a wide menu and a nest-building male.

Read the book. Print this page for the key.

Questions and answers

1. What did a 2005 study conclude about shoaling?
   • It is only for hunting
   • It has a cover-seeking function (answer)
   • It is only for sleeping
2. Where are the younger piranhas in a shoal, typically?
   • Toward the outside (answer)
   • In the center
   • Far away
3. Where do red-bellied piranhas typically live?
   • Blackwater streams
   • Cold lakes
   • Whitewater streams in South America (answer)
4. When does spawning seem to occur?
   • In deep winter
   • During the wet season (answer)
   • In the dry season
5. What does the group do for a red-bellied piranha?
   • It gives protection (answer)
   • It makes the fish faster
   • It builds the nest
6. What is a piscivore?
   • A plant eater
   • A bird
   • A fish eater (answer)

Words

• shoal: fish group
• defence: staying safe
• spawning: laying eggs
• courtship: a pairing dance
• piscivore: fish eater