Thursday, September 6, 2007

620 Fear of the Dark

Message no. 620[Branch from no. 603] Posted by Thomas Culhane (1311520071) on Wednesday, March 14, 2007 4:38pm Subject: Fear of the Dark

The year I was doing research in the primary rain forests of Borneo I gave a lot of thought to fear of the dark. It seems that we diurnal primates sacrificed good night vision for good daytime color vision (a lot of it has to do with the distribution of rods and cones in the eye). This enabled us to see when fruit was ripe as well as avoid eating dangerous insects with toxins indicated through "aposomatic coloration". But the cost of great color vision was an insensitivity to low light conditions. Predators, on the other hand, sacrificed color vision for night vision. I can't forget seeing the bright shine of the eyes of jungle cats and civets when I would walk to the toilet pit with my kerosene lantern at night. The shine was an indication of the light gathering ability of these low lux marvels of evolutionary design and creation. The animals with good night vision would come out after the sun set to revel in their world whilst we primates would huddle fearfully in our huts or in our tree nests until the sun rose again.

Orangutans were particularly slothful at night. They would start building their nests in the safest tall trees at about 4 in the afternoon (the sun set at 6 in the tropics) and lie there for an hour tossing and turning trying to make it as comfortable as possible before night fell. They would then sleep until about 10 the next morning and only then crawl out of the nest to look for fruit or play. The gibbons were up at dawn, calling and defending their territories with their beautiful mournful songs, and they would sing again at dusk. Then they too would find a safe place to sleep.

The jungle in the day and at night were two different worlds completely. I did a bat study with some friends and we would go out at night with night vision scopes. We would sit under trees or near caves in the pitch black and then turn on the night vision scope. Suddenly the world would appear in bright green (you have seen the military use these in Iraq I think!). These scopes show us what the world must look like to the creatures of the night. Through these scopes we saw the world of the night animals in rich detail (but never in color!!). I tried to imagine how bats and flying foxes see, since unlike the other predators, they don't use light, but sonar, as you know! They "see" in pulses of sound, like dolphins and whales do. I also would try to imagine how snakes and other creatures with thermal receptors would "see" -- in infra-red. Kind of like the way the alien Predator in the movie "Predator" sees, I imagine.

Have you seen the movie "Pitch Black" with Van Diesel? I think it gives us a good idea of why we fear the dark, and what the advantage would be if we, like Diesel, had implants that enabled us to see in the dark.

Fear of the dark is species specific, and it probably is in our genes to learn to fear the dark easily so we wouldn't make the mistake as children of getting up at night and wandering around. But today our technology may make it possible to live without fear of the dark, for as you know, there is nothing in the dark that isn't there in the light -- its just the inability to perceive it that makes it so scary.

Perhaps soon we won't have to carry flashlights into dark places, but will be simply able to turn on our "night vision eyes."

Imagine a world with no unsightly street lights and car headlights - a world in which we don't have to modify our environment because we have the ability to modify ourselves instead. Wouldn't that be the ultimate in coping and adaptation?

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