These are the final words of Johan Eklof’s book The Darkness Manifesto, at least half of which is about light, naturally. Although it calls attention to the looming threat of light pollution to our planet’s biota, the work includes new fun facts about vision, plus the good news that this problem is easily solved, with examples of piecemeal progress.

As with many of our self-imposed crises, this one mostly affects non-human animals. Birds, bees, bats, and insects are among the creatures so dependent on natural light cycles that they literally stop mating, or fail to successfully feed, when signals from the sun, moon, and stars are blocked by artificial lights. Yes, stars. Amazing numbers of animals, most of them very, very small, rely on information from starlight to live, including the location of Polaris. Some even react to the zodiacal light.

Many plants also require a certain number of consecutive hours of dark/light to flower or set seed. The interactions among pollinators, ie all the animal types listed above, and plants, including timing coordination, are threatened on a fairly large scale, as described in the most worrisome sections of the book. Insect populations in particular have decreased by at least one-third in the last fifty years, and possibly closer to three-quarters. Kids my age, do you remember all the insect splats on the car windshield during family vacations? If you still take long distance drives, as we certainly do in the Golden State, you’ll know that’s no longer a problem, unless you just happen to encounter a Biblical event in progress.

Humans aren’t immune from the effects of decoupling our wake/sleep cycles from nature either, with sleep deprivation (duh), obesity, and some cancers already linked. An amazing hospital in Sweden with interior lighting that mimics outside light in color and intensity all day long, then at night provides minimal illumination only where needed, claims to have seen health improvements among both patients and staff. Having spent late hours in glaring ER lobbies, I believe it.

In order to take advantage of light/dark cycles, creatures have to be able to perceive and process some portion of the electromagnetic spectrum, and since the sun, moon, and stars predate all life, nature has evolved lots and lots of those systems. I thought I knew the human version pretty well, and was amazed to learn that we all have excellent greyscale vision after dark. To achieve this ultimate night vision, you have to be away from artificial light for 30-60 minutes, and the clock resets every time you peek at your phone. Some millennials living in megacities like Singapore and Hong Kong may have reached adulthood without once experiencing this.

I knew that our eyes contain rods for grey vision and cones for color vision. I did not know that while we have three cones, and birds have four, the color vision champion of the world is the mantis shrimp, with 16 cones! Humans have no way to even imagine what “colors” the mantis shrimp can see. We can do a little better guessing what animals that have ultraviolet or infrared vision might be seeing, since we have created instruments that can “look” with those spectra. Migrating birds though, may use quantum entanglement in their eyes to see–no quotes!–the Earth’s magnetic field. I imagine looking down from the window of an overnight flight at a glittering geodesic sphere enveloping the Earth.

Reducing light pollution with timers, motion detectors, downward-facing shades, and red-spectrum or reduced intensity sources are some of the current-technology fixes that could rapidly turn this problem around, and light designers, who see themselves as artists working with light and shadow, have embraced this book. Darkness is being recognized and protected around the world from national parks to city suburbs. Deep-darkness vacation destinations, from the obvious astronomical-phenomena-based ones to nighttime safaris, are now a thing.

Need another reason to read it? The chapters are short and the book is slender.

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