From learning to dougie to summoning rain, different types of dancing evoke a variety of emotions and are used for many distinctive purposes. For Collembola (commonly referred to as springtails), our featured bugs this week — a good dance might just find you a girlfriend.
The “Cha-Cha-Cha”dance of one species of springtail (not to be confused with our “Cha-Cha Slide”) is a dance that involves a series of head-butts (seen above) with a grand finale of two twirls. While it may seem aggressive to the human eye, this dance, when completed satisfactorily, woos a female Bourletiella hortensis into accepting a male’s sperm packet, or spermatophore. However, if she is less than impressed, the female declines his offer and eats the spermatophore instead! These sperm sacs must be nutritious, because males of the Orchesella cincta species are often seen eating the sperm sacs of other males. Scientists propose that by eating competing males’ sperm, Orchesella cinta increase the chances of their sperm packets being chosen by neighboring females instead.
As an alternative to dancing, some male springtails use the “love garden” technique, planting a series of spermatophores in an area and then coaxing a female springtail to walk through and pick up sperm along the way. Other males are much more strategic with their placement of sperm. Some use the “ring of fire” method, which involves building a fence around the female, practically forcing her to walk over a sperm packet if she wants to leave. However, some males in this Order are much more careless, haphazardly depositing their spermatophores and hoping that a female will find it. This reproductive method is known as “drop and pray.” Lastly, others use the “tug of war” technique. After laying a spermatophore, a male grabs onto a female with his antennae and forcefully brings her over to it. In species that don’t directly transfer sperm, males have to get a little creative.
In addition to their different mating rituals, springtails also exhibit other interesting behaviors. Some members of the Order can jump anywhere from 15 to 20 times their own body length when threatened, using specialized legs that are normally kept tucked against their bodies. This is equivalent to a 5’5” tall person jumping over 8 stories high. This amazing feat earned them their nickname “springtails.” To land safely after such a leap, it was once thought that Collembola had a specialized organ which allowed them stick to whatever they landed on. In fact, this is how the Order got its scientific name. The greek roots kolla, meaning glue, and embolon, meaning peg were combined into Collembola. Unfortunately, scientists made a mistake. This “glue-peg,” which is located just before the third set of legs, is actually used in transporting water in and out of the individual, not to stick to surfaces. Despite this, the name stuck and over 200 years later the bug is still known as Collembola.
Considering how Collembola are so cool, why aren’t people talking about them? They are so tiny! Even at their largest size of 6mm, you could still fit three end to end on a penny and have room to spare. These bitty bugs can be found anywhere from within soil, leaf litter, and decaying wood to the surfaces of water or snow. While they much prefer to be the one chowing down on some decaying leaves, mold, or mildew, these tiny bugs often find themselves on someone else’s dinner plate. Other insects and arthropods such as spiders, mites, flies, and pseudoscorpions perceive them as tasty snacks rather than friendly neighbors. You would think with up to 8 single eyes on each side of their head they would keep a better lookout! Regardless, if they can see you coming with their multitude of eyes, you should definitely keep your two on the ground. You never know when you might run into a leaping Collembola.
By: Kallin Lang
Feature photo by Andy Murray, Flickr.