Think of the Earth as a giant cherry tomato with skewer running right through it. Scientists believe that while our solar system was in the process of forming something really big, another “protoplanet” hit the Earth and slapped it out of kilter. So, as most kids forget by the end of high school, the Earth spins on a skewer that is 23.5 degrees off its orbital axis. As the planet takes its yearly trek around the sun, the Northern hemisphere either receives direct light, as in summer or indirect light, as in winter -- which creates seasons that are “near perfectly calibrated to maintain life”, according to Universe Today. Thanks to that skewer, New Englanders enjoy (or loathe as the case may be) typically long, cold, and snowy winters.
As winter winds down in New England, ice and snow begin to loosen their grip on the landscape, and signs of spring begin to emerge, sometimes literally right out of the snow. By March steam pours from vents of sugar-houses as sugar-makers begin boiling maple sap down into Vermont’s signature liquid. On those same late winter days when the temps begin to push into the 50s and the streams begin to run full of snow-melt, a hiker or skier might come upon a patch of snow that looks at first like it was dusted with cinders or black sand. That black on white contrast arrests the eyes.
What at first looks like fine dirt turns out to be a little millimeter-long hexapod, the springtail, or as they're colloquially known, "snow fleas". Various springtails exist all over the planet, but they somehow manage to persist even in extreme winter climates like Antarctica and northern New England. These intrepid little snow enthusiasts turn up by the thousands per square meter, up to 10,000 of them in fact, according to legendary naturalist David Attenborough. Even at high elevations, in late winter springtails emerge from the snow in huge numbers on warm afternoons in order to feed on decomposing leaves or moss. Snow fleas represent not only the inevitable arrival of spring in the northern woods, but some of nature's amazing adaptations that allow for a specie's survival -- and perhaps has some benefits for humankind as well.
As winter winds down in New England, ice and snow begin to loosen their grip on the landscape, and signs of spring begin to emerge, sometimes literally right out of the snow. By March steam pours from vents of sugar-houses as sugar-makers begin boiling maple sap down into Vermont’s signature liquid. On those same late winter days when the temps begin to push into the 50s and the streams begin to run full of snow-melt, a hiker or skier might come upon a patch of snow that looks at first like it was dusted with cinders or black sand. That black on white contrast arrests the eyes.
What at first looks like fine dirt turns out to be a little millimeter-long hexapod, the springtail, or as they're colloquially known, "snow fleas". Various springtails exist all over the planet, but they somehow manage to persist even in extreme winter climates like Antarctica and northern New England. These intrepid little snow enthusiasts turn up by the thousands per square meter, up to 10,000 of them in fact, according to legendary naturalist David Attenborough. Even at high elevations, in late winter springtails emerge from the snow in huge numbers on warm afternoons in order to feed on decomposing leaves or moss. Snow fleas represent not only the inevitable arrival of spring in the northern woods, but some of nature's amazing adaptations that allow for a specie's survival -- and perhaps has some benefits for humankind as well.
First though, they’re not technically insects. Besides the number of body segments and the lack of compound eyes, an extra little appendage sets them apart from their taxonomic cousins: the spring tail which gives them their name. Called a “furcula” (same word root as “fork”), this adaptation seems particularly designed to allow the springtail to evade predators. The snow fleas’ exoskeleton is full of a “rubber-like protein called resilin, where a lot of the potential energy for the jump is stored,” according to an article in Wired magazine. Basically, springtails are always running around cocked and loaded. When threatened by a predator, like a spider or centipede, they deploy their ejection seat and launch 100s times their body-length -- the equivalent of a person jumping over the Eiffel Tower (Attenborough). Unfortunately for these spring-loaded little launchers, they cannot control where they land, so their jump is a sort of randomizer. Then again, when there’s a party of 1000s of snow fleas, it probably doesn’t matter where you end up -- they just hop to the other side of the fiesta.
Still, the springtail has to survive the winter to make it to these spring bacchanals, and to weather the long New England winter, even at high elevations where winter runs even colder and longer, the snow flea uses a built-in anti-freeze to make it through. Tiny peptide chains known as anti-freeze proteins (AFPs), they allow a variety of organisms, among them fish, fungi, and plants, to survive extremely cold climates. AFPs operate at the molecular level “by binding to the surfaces of ice crystals as they start to form, inhibiting further growth,” according to an article by Steve Ritter in Chemical & Engineering News. By preventing the formation of ice crystals, AFPs prevent organisms from freezing solid, thus ensuring survival.
Snow fleas have another chemical defense, this one specifically designed to deter predators: a chlorine compound called Sigillan A. Researchers in Germany have isolated something that “is unique in that it is a new class of natural products that features a chemical scaffold that could find application in insect control,” as reported in an article by Sarah Evarts in Chemical & Engineering News. Scientists were surprised to find any chlorine compounds at all produced by a land animal. “It’s not often that scientists find any halogens in natural products made by terrestrial organisms … here, there’s not just one chlorine, but five chlorines,” according to John Pickett, chemical ecologist from Rothamsted Research Station in England.
Snow fleas’ chemical adaptations, AFPs in particular, may come to help humans in a couple of ways, perhaps most importantly with organs for transplant. According to a piece in Phys.org, Drs. Laurie Graham and Peter Davis [of Queens University] “found that the potent protein produced by the fleas to protect themselves against freezing is capable of inhibiting ice growth by about six Celsius degrees.” This is significant because it would allow “organs to be stored at lower temperatures, expanding the time allowed between removal and transplant.” Moreover, snow fleas’ AFPs break down easily at higher temperatures. This is beneficial, explained Dr. Davies, Canada Research Chair in Protein Engineering, because AFPs used for organ transplant storage “will be cleared from a person’s system very quickly, reducing the possibility of harmful antibodies forming.” Thus, the potential for successful transplants increases dramatically.
Other studies show that springtail chemistry may also help bring about more effective freeze-resistant crops. But aside from their promising contributions to humanity, snow fleas are decomposers, and as such they perform an arguably more important role for humans: helping to maintain the balance and health of our northern forests by facilitating the breakdown of organic material. Decomposers maintain a healthy soil substrata on which trees and forests can thrive. And with those forests spread all over this skewed and changing planet, the humans who occupy it, for now, are still able to breathe.
Very interesting. Thanks for posting.
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