Insects

Everybody is familiar with Grandaddy Long-Legs with the long, slender gams and little egg-shaped bodies. These fascinating little characters are related to spiders, but they are not spiders. Here is the good news--THE ARE ABSOLUTELY NOT POISONOUS and are completely harmless to humans, so we can toss that old myth right out the window. They do not have venom glands or fangs, and their grasping claws, typically very tiny, are not strong enough to break human skin. So, no need to worry any more.

The most obvious difference between spiders and Opiliones, also known as Harvestmen, is that spiders have a body divided into two parts, whereas the Opiliones' two parts have fused into one so they do not have the alluring waistline of a spider. Opiliones also have no spinnerets for making silk or webs, so if you see one in a web, it is most likely about to be food. Unlike most spiders that must liquefy their food, Opiliones can eat chunks of food. Spiders have eight eyes while Opiliones have two eyes that perch on a bump atop their head aiming outward. They have a heart that pumps blood (hemolymph) and a brain.

Opiliones and spiders are of the Animal Kingdom and both are Arachnids, but spiders are of the Order Aranaea and Opiliones are an Order all their own called, simply, Opiliones. Neither spiders nor Opiliones are insects. Opiliones are most closely related to mites, ticks, aphids, scorpions, and pseudoscorpions. It is believed that Opiliones are helpful to the environment.

Opiliones are extremely old, coming from a genealogical line going back at least 410 million years to earth's geological Silurian period. Apparently they first lived in the oceans but decided to leave the water around this period. Remarkably, the oldest fossils, which were found in Scotland, have barely discernible differences to modern Opiliones. It is an astounding achievement to have survived so long.

Opiliones have adapted to many micro-climates all over the world but they like damp forested areas the best (such as around a lake.) They are greatly diverse in size, colors and behavior adaptations. Adults usually hide during the day and begin foraging at twilight. They remain hidden throughout winter and are most commonly seen in late summer and fall, which is probably how they got their name. Many species of Opiliones tolerate their own kind and will form aggregations up to 200 or many more. This may be a protection against climate and against predators, with the effect of strength in numbers. It could also enhance their group stink bomb.

Opiliones are omnivorous and will eat plants or prey. They scavenge dead organisms or ambush those that are slower and smaller. They catch prey with their tong-like pincers (in place of fangs) near the mouth, with which they dismember their food. Opiliones eat small insects, snails, caterpillars, veggies, fungi, carrion and dung, plus juices and material from plants and fruits. This varied diet is unusual for arachnids as arachnids are usually pure predators. Opiliones, in turn, are also food for birds, spiders and others.

Unlike spiders, most Opiliones breed directly. In some species the male may guard the female after mating and some may defend territories. The female may lay eggs soon after mating, or it may not be until months later. Some lay eggs on the ground, under stones, or in crevices of wood, and some build nests. In some species only the male takes care of the eggs, cleaning them regularly, and often guarding them against egg-eating females. The eggs hatch any time after 20 days or up to six months after being laid, depending upon temperature and species. Most hatch in the Spring, looking like tiny adults, then there are usually six nymphal stages to maturity and they must moult a hardened outer covering each time (exoskeleton) in order to grow. Most Opiliones live about one year in the Northern U.S. and most die in the winter after eggs are laid.

Some of their enemies are birds, mammals, amphibians, spiders, mites and ants. Defenses depend on the species and include shaking their bodies, feigning death by becoming rigid, or gluing debris onto their bodies. Opiliones are usually agile and fast, but if grabbed by a predator, many can easily release a leg that will keep twitching, most likely to confuse the attacker while the Opilione makes his getaway. Unfortunately, the leg will not grow back. The Opiliones' wickedest and best defense is their odiferous (prosomal) stink glands that are used to deter predators, but only as a last resort as it is a high energy cost. It may also serve as an alarm pheromone for others.

There has been a lack of research on Opiliones and the information is challenging to piece together, but there is much more about them that is not included here. I started this to simply find out if Grandaddy Long-Legs really are poisonous as is popularly believed and quickly found myself up to my nose in a sea of peculiar names that are barely spellable or pronounceable. But, even after the close call with drowning in all the alien minutiae, I began to appreciate these little guys. Still, I prefer that they stay outside of my house; but I will certainly think twice before harming one now.

A computer site for excellent close-up photos is: http://www.flickriver.com/photos/tags/opilion/interesting

There is one insect, the Antarctic midge -- Belgica antarctica -- that lives on the Antarctic Peninsula. This animal takes two winters to develop through larval stages into adulthood, and survives high wind, salt water and extreme UV rays. It lives for about a week, mates, and then dies.

From its Wikipedia page: "To adapt to the cold temperatures, B.antarctica accumulates trehalose, glucose, and erythritol." These chemicals reduce the amount of ice that forms in the insect's body.