A growing body of evidence indicates that light — in this instance artificial light — acts as a drug on the body. Light isn’t a drug, but it affects circadian rhythms and influences certain hormones.

All light wavelengths are involved, but especially blue wavelengths. That’s important because blue wavelengths are emphasized in the light emitted by many electronic devices and energy-efficient lamps. Blue wavelengths, in turn, are especially able to adversely affect the production of the hormone melatonin in our bodies.

Melatonin promotes sleep and alerts a variety of biological processes one is generally aware of. Light hitting the retina of our eyes suppresses the production of melatonin and messes with your sleep pattern.

How much light may affect circadian rhythms or if it can affect your health is being studied. Artificial light was invented only about 130 years ago. Not that long ago. (Firelight doesn’t seem to have been studied but probably contains more red wavelengths than blue ones.)

Investigators feel that any kind of light late in the evening can have broad health affects, aside from sleep disruptions. Blue light may improve cognitive abilities. Well, sleep rhythm concerns will not be forgotten. A whole slew of research opportunities opens up.

Artificial light won’t go away either, one assumes. How can modulation alter our lives? What effects are being seen in domestic and wild animals?

Something to keep an eye on.

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Local author Earle Layser sent along a clipping on light wavelengths that are invisible to us but that some other mammals (reindeer) can see. Birds are renowned for seeing in the ultraviolet range.

The article, from some unidentifiable wildlife source, notes that normal humans are able to see three primary colors, whereas many other organisms can see four or more color channels. Butterflies see five color channels and five primary colors, so presumably are able to distinguish up to 100 billion combinations.

What a wondrous world.

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Field Notes: About 5 p.m. Dec. 20, June and Michael McCollister reported a grounded great gray owl walking in a John Dodge neighborhood. Unable to fly but still hunting; when taken by the Teton Raptor Center personnel next day, it had just caught a vole. The adult female great gray had been walking for at least four days, unable to fly because of a fractured bone in her left wing. The wing was immobilized, and rehabilitation is expected to be successful. The owl will then be released. Look for an announcement. Nice to report a happy ending. The McCollisters also noted a second great gray in the vicinity on those four days.

Franz Camenzind spotted a Townsend’s solitaire taking a drink through a tiny opening in otherwise frozen Flat Creek on Friday.

Also on Friday, Sue Perkins was pleased to find a great horned owl perched in daylight only seven feet away on a railing. Reports of hundreds of rosy finches in isolated flocks, wintering Northern flickers, common redpolls, a Harris’ sparrow and various finches, and a few Clark’s nutcrackers.

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The Teton Valley, Idaho-Wyoming Christmas Bird Count was held Jan. 5. Compiler Susan Patla reports 55 species, including five hawk species; also 205 common redpolls and 47 evening grosbeaks.

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And now winter seems to be settling in. Respect our wildlife.

© Bert Raynes 2013

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Bert Raynes writes weekly on whatever suits his fancy with a dash of news on nature and its many ways.