Sunday, April 10, 2011


What is seeing?

Right. We do it with our eyes.

But is seeing a strictly visual thing? When describing the way other animals perceive the world we often say that they "see" with other senses. Bats might "see" their prey with sonar. Odontocetes (toothed whales) "see" with echolocation.

When talking about different animals we use this word "see" when talking about the animals primary sense, the sense with which they extract the most information from the external world. Dogs are primarily olfactory creatures. Most of the information they process is through the nose. Instead of using eyes to visually determine the difference in individuals the way we do they smell one another. Sharks are also olfactory creatures with up to seventy percent of their brains devoted to smell.

When this is process is described (extracting detailed information using a sense other than sight) it is often described as "seeing" even though "seeing" seems to be a visual word. There may be a good reason why, though. Our brains (human brains) construct images of the world by processing light waves coming into our eyes. But sharks, dogs, bats and dolphins also construct images of the world. Even though those images are not based on light waves they still, it seems from research, really do "see" the world around them. It's just that those images are constructed from detailed information in the olfactory spectrum or from echoed sounds.

Last night while watching one of the great David Attenborough nature documentaries, "The Life of Mammals" I was reminded that there is at least one member of the animal kingdom that "sees" not with its eyes, ears or nose but with its hands. And it just happens to be a New England Native. Who is it?

Procyon lotor: the Raccoon. In the same family as cats and dogs the raccoon has evolved towards a more varied diet but feeds mainly at night in freshwater ponds and streams. If you watched it hunting in the pitch blackness of a dark New England wood you might mistake the behavior for merely fumbling along, front paws splashing quietly in the water. But you'd be missing the orchestra of neuronal impulses firing in the raccoon's brain. It is by no means merely fumbling along. The "hands" of the raccoon are so sensitive that they can, like our eyes and a bat's ears, literally construct an image of what's on the riverbed so acute that the animal is capable of telling the difference between a rock and a clam in a split second.

There are actually a lot of very interesting and unique things about this New England creature and I hope to return again to it in future posts. I'll probably never get a shot of one though so if you want to see images, as always, head over to EOL.

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