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Creatures of the Deep: Spineless, But Smart

The octopus of myth and legend is really a shy, intelligent creature. In fact, the octopus has the most highly developed brain of any invertebrate. Scientists once assumed that because the octopus has a simple nervous system, its brain is fully programmed at birth. Italian biologist Graziano Fiorito is challenging that notion. He sets up an experiment to observe pairs of octopuses in action. Their behavior suggests that an invertebrate can learn by watching.

Curriculum Links
Background Information: Meet the Octopus
Activity: Investigate a Midden



sensory detection

animal behavior,
ocean life




social studies


The octopus belongs to the family of marine mollusks that have soft bodies covered by a thin envelope of flesh. The octopus belongs to the class of mollusks known as Cephalopoda (from the Latin "head-feet"); other cephalopods include squid, cuttlefish and the pearly nautilus.

Because it has no shell, the octopus is able to slide its soft, rubbery body into crevices in rocks and reefs. It is in locations like this that the octopus makes its lair. An octopus stays in or near its lair most of the time. It uses its long tentacles to tear mussels from nearby rocks or snag passing crabs or similar sea creatures. As a result, the entrance to an octopus lair is usually partially blocked by a pile of broken and empty shells, the waste products of its meals. This garbage heap -- or midden -- can be used to locate an octopus during low tide.


Not only is a midden useful for helping to locate an octopus during low tide, but it can also reveal much about the octopus itself. For example, the size and contents of the midden indicate the amount and variety of foods in the octopus diet. The size of the midden also suggests how long the octopus has lived at that particular site. The middens of other animals, like rodents, reveal similar information about their builders.

In this activity, you will investigate a rather common but often overlooked midden -- the school lost-and-found. Divide into groups and work on tasks selected from those on this page.


Use everyday objects to make connections across the curriculum. Like the octopus with its far-reaching tentacles, one idea can have far-reaching applications.


Bring items from the school lost-and-found to the classroom. Inventory the items. Through discussion and examination of the lost articles, try to answer the following:

  • MATH CONNECTION: How many items belonged to boys? To girls? How many to people whose gender could not be determined by the item? Graph the results.

  • LOGIC CONNECTION: Hypothesize reasons why the items are lost.

  • INVENTION CONNECTION: Design improvements to selected items that would reduce the chance of their being lost or, if they were lost, that would help their owner locate them more easily.

  • ANTHROPOLOGY CONNECTION: Catalog the items found in a contemporary midden: consider the trash that accumulates in your home as your family's midden. Can information about the family's size, diet or other activities be determined by what is found there? What would your midden say about you?

  • LANGUAGE ARTS CONNECTION: Imagine that all the items were lost by one family. Write a story about the family based on the items they left behind. Or, write a story about one lost item.

  • COMMUNITY CONNECTION: Compare and contrast the lost-and-found collections in other community locations with the one in your school. Visit other facilities and return with a sample inventory of the items found there. Investigate other district schools, the police department, department stores, the library, the airport, etc.

  • HISTORY CONNECTION: Archaeologists and anthropologists use the kitchen middens of older civilizations to learn about life during that time period. Work with the history teacher to develop lists of what might have been found in middens in different historical eras.


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