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Guide Index

Fixing the Leaning Tower of Pisa

All in the Family

Long-distance Doc

Spineless But Smart

Eruption!

Where's the Matter?

Renaissance Machines
in the classroom
TEACHING GUIDES


SCIENCE ITALIAN STYLE: Spineless But Smart


The octopus may be smarter than anyone knows. Because the octopus is an invertebrate with a simple nervous system, biologists have always assumed that its brain was fully programmed at birth. But an Italian biologist is challenging assumptions about octopus intelligence. Intrigued by octopus behavior, Graziano Fiorito sets up an experiment to observe a pair of octopi in action. For the first time, he shows that an invertebrate can learn by watching another of its species.

Curriculum Links
Activity 1: Jet-propelled Locomotion
Activity 2: Visual Memory



CURRICULUM LINKS

BIOLOGY

anatomy, neuron,
physiology, sensory detection
CHEMISTRY

solutions
LANGUAGE ARTS

non-verbal communication


LIFE SCIENCE

cephalopods,
invertebrates, taxonomy
MATH


probability
PHYSICS

force, motion,
Newton's Third Law,
rotational motion
PSYCHOLOGY

behavior, learning,
memory, neural pathways,
visual learning



ACTIVITY 1: JET-PROPELLED LOCOMOTION

Octopi, like other cephalopods, propel themselves with jets of water. The ejected water, forced out through a siphon hole, causes the octopus to move in the opposite direction. The following activity models this style of locomotion.

MATERIALS
  • kite string
  • balloons
  • straws
  • tape
  • scissors


PROCEDURE
  1. Cut a length of kite string about 5 meters long. Thread the string through a straw.

  2. Tape each end of the string to a chair. Place the chairs apart so the string is taut.

  3. Inflate a balloon. Squeeze the open end closed and tape the side of the balloon onto the straw.

  4. Release the balloon.


QUESTIONS
  1. What causes the balloon to move?

  2. What force causes air to shoot out of the balloon?

  3. Explain the connection between your observation and Newton's Third Law of Motion.


ANSWERS
  1. A jet of air.

  2. Pressure exerted by the sides of the stretched balloon.

  3. As the air is expelled in one direction, the balloon moves in the opposite direction, demonstrating the concept in Newton's Law.




ACTIVITY 2: VISUAL MEMORY

As you've seen on FRONTIERS, visual memory is a requirement for learning some types of activities -- even among octopi. How good is your visual recall? Here's a simple activity that requires a friend and a deck of cards.

PROCEDURE
  1. Team up with another person; one should be the subject and the other, the investigator.

  2. The investigator should display one card from a shuffled deck to the subject for about one second.

  3. The subject must correctly identify which card was flashed.

  4. Next, the investigator displays two cards, each for one second. The subject must correctly recall the two cards in the exact order they are shown.

  5. The investigator repeats the experiment, adding one more card each time the cards are drawn and displayed to the subject. When the subject misses the sequence twice in a row, the test is over. Record how many cards the subject was able to memorize.

  6. Switch roles and repeat Steps 2 to 5.

  7. Repeat the experiment again, but instead of showing the card to the subject, verbally identify the card to the subject.

  8. Tally the class data. Analyze the data and display the results as a bar graph. Try the same experiment with subjects of different ages, including children and adults. Compare results.


QUESTIONS
  1. What was the average number of cards a subject remembered in the two experiments? Why do experiments like this one look for averages?

  2. Would shuffling the cards after each round affect the results?

  3. How did a subject's auditory recall compare to his or her visual recall? Can you explain the different results?


ANSWERS
  1. Answers will vary. In a psychology experiment, it is critical to average the subject's responses. Students shouldn't depend on one response, which could be a fluke; data must be repeatable and representative of several trials.

  2. It would make it slightly more difficult, due to the increase in displayed card choices.

  3. Answers will vary, but many students will have poorer recall when memory is based solely on auditory experience.









 

Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.