Worms Who Use Their Brains

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Scientists have shown that ordinary earthworms show signs of significant intelligence.  For example, when worms draw leaves through the narrow entrance of their burrows they either roll the leaf up or grab it by the pointed end.  They often try several holds on an irregular leaf to find the optimum pulling point.

Given a mixed pile of grass, pine needles and other assorted herbage, worms first eat the soft material.  Then they will bury the hard stuff, like pine needles, to age them for future consumption.

Worms can even be taught which way to turn to avoid trouble, a skill some humans lack!  Scientists constructed a ‘T'-shaped maze with one arm lined with sand paper and an electrode which gave a small shock.  The other arm contained only earth.  The worms soon learned to turn to the more appealing branch.  Other scientists claim to have taught worms to remember how to crawl through a series of difficult mazes.

Worms have an amazing ability to regenerate.  The severed heads grow new tails, and the tails grow new heads.  The interesting thing about worm intelligence and memory is that both pieces of the severed worm show the same ability to follow the same learned paths that the original uncut worms did.  Experiments like this are challenging our ideas about where memory is stored.

So next time you see a worm, don't look down on it - remember that it's not totally bereft of either intelligence or memories.