One Brain and Eight Clever Arms: teacher key

Giant Pacific Octopuses, grade 11 edition, written for 11th grade. Where is an octopus's intelligence? Follow the evidence from mazes, genes, sleep and a 2021 review, and see where scientists still disagree about what an octopus mind is.

Read the book. Print this page for the key.

Questions and answers

1. What did the researcher who led the 2020 maze study call the octopus?
   • A swimming mind with no arms
   • An octopus with one brain and eight very clever arms (answer)
   • A small fish with a big brain
2. Which part of the octopus brain plays an essential role in learning and memory?
   • The vertical lobe (answer)
   • The beak
   • The siphon
3. Why is comparing cephalopod and vertebrate brains a challenge?
   • They evolved independently for more than 500 million years (answer)
   • They are the same size
   • Cephalopods have no brains
4. Scientists debate how to define a tool. What does that mean for coconut carrying?
   • Whether it counts as tool use is argued (answer)
   • It is definitely not tool use
   • It has been proven to be tool use
5. What did the 2021 London School of Economics review conclude?
   • Octopuses should be regarded as sentient (answer)
   • Octopuses cannot learn
   • Octopuses are insects
6. What does bycatch mean in: its value as bycatch?
   • A kind of bait
   • Animals caught along with the fish being sought (answer)
   • A special net

Words

• neurons: nerve cells
• sentient: able to feel
• protocadherin: cell-sticking gene
• bycatch: unintended catch
• plankton: drifting life