Snow fleas have been out and about this past week.
Despite their name, snow fleas bear no relation to the parasitic insects. Truth be told, snow fleas aren’t even insects! They have six legs, but aren’t divided into three body regions like insects, so instead belong to a larger grouping, the hexapods. Snow fleas are more properly called “springtails”, after the furcula, meaning “little fork” in Latin, a forked structure they use to fling themselves into the air.
Here’s a close-up video of a distantly-related springtail leaping, with a bit of an explanation of how the furcula works.
Unlike many arthropods, springtails grow to maturity faster in cool and moist conditions. Many are winter-active as well.
Similar to some of the insects I discussed in our piece on cold adaptations, many springtails have glycerol compounds in their blood, which lets them stay active in cold temperatures. Some food scientists are currently studying this blood antifreeze to make ice-cream less-susceptible to freezer damage.
Here’s a broader-field video than I was able to take of the snow fleas.
Despite being very common, and covering a vast range, very little is known about springtails. Most tend to live in the soil itself, either in woodlands or grasslands, but I’ve found them in caves and on the surface of streams before as well. Wherever there is moisture to keep springtails from drying out, as well as bacteria or mold for them to eat, there you can find springtails.