Thirteen Things You May Not Know About Spiders

Remember singing, “The Eency, Weency Spider” when you were a child? Or reciting the nursery rhyme about “Little Miss Muffet” who was frightened by a spider? How much did you actually know about spiders then? How much do you know today? Here are thirteen facts you might find interesting.

1- There are more than 40,000 species of spiders in the world. Spiders can be found on every continent except Antarctica, in habitats as diverse as mountains, deserts, woodlands, farm fields, wetlands, basements—and under the chair on which you are sitting as you read this. There are more than 2,000 species of wolf spiders alone.

2- Many spiders are helpful to human beings. They eat a lot of mosquitoes, aphids and other insects. It has been estimated that spiders are responsible for 99 percent of insect deaths. Some California rice farmers put wolf spiders in their fields to keep down the population of insects that harm their crops. A British researcher, W. S. Bristowe, concluded that spiders eat more prey than all other carnivores combined. In fact, the weight of the insects they eat each year exceeds the weight of all the human beings living in England.

3- In some parts of Asia and South America, large spiders (such as tarantulas) are on the menu. They are a good source of protein. I have not tasted them, but some people say they taste much like chicken.

Many fish, mammals and birds eat spiders. Some birds even make use of spider silk when they build their nests.

4- You probably already know that spiders (and other arachnids) have eight legs, and that their skeletons are on the outside of the body. You almost surely are aware that many spiders spin silk threads and weave them into webs. But did you know that spiders’ silk thread is as strong as steel wire of the same thickness? And that it can be made into silk fabric the same way silkworm silk can be? Did you know that many of the Asian spiders called mesothelids make burrows or holes in which to live, and line them with strands of silk? A spider web can last as long as a year. A web discovered at Lake Tawakoni State Park in Texas in 2007 stretched between trees 200 yards apart. The largest web on record, it may have been built by numerous spiders. Some spiders wrap prey in silk threads so they can snack on them later.

5-Different spiders use different tactics to capture prey. Some trap insects in their webs. Some, such as wolf spiders, wait in ambush for an insect to come along and pounce on it. Other spiders spit on, lasso, or fish for prey. The mesothelids mentioned above make trapdoors for their underground dwellings. Strands of silk lead out from the tunnel or hole. When an insect touches one of those strands, the trapdoor opens, and the spider grabs a quick snack.

6-Various spiders have different defenses, also. The tarantula, when threatened by a bird or animal, rubs its legs against some of its urticating hairs. The hairs fly off the tarantula toward the predator. If they hit the eyes, mouth or nose, they cause enough pain that the predator is likely to back off. Pirate wolf spiders build silk tubes underwater and hide in them when threatened.

7-The spider web got the name “cobweb” when spiders were called cobs.

8-Spiders are believed to have been around since the Cambrian period (which lasted from about 545 million years ago to about 530 million years ago) or soon thereafter. During the Cambrian period, all life was in the sea; plants had not yet developed. Most scientists believe the first arachnids were scorpions, because they discovered scorpion fossils with gills. Also, their legs were too small to support their bodies, which were much larger than the bodies of present-day scorpions.

9- Many of the same species of spiders exist in both North America and Europe; they probably stowed away on ships, crossing the Atlantic Ocean with people and trade goods.

10- Some spiders, including wolf spiders, are ectothermic, which means that their body temperature rises and falls with that of the environment. When the temperature falls too low, these spiders become inactive.

11- Some female spiders have a reputation as good mothers. A female wolf spider, for example, builds an egg sac, and attaches it to the spinnerets at the end her abdomen. Here she keeps her eggs safe. She has to keep her abdomen raised when she walks, so the sac doesn’t drag on the ground. When it is time for her babies to hatch, she bites the sac open. The babies climb up on the mother, who carries them around for about a week, until they are ready to live on their own. In Brazil, a funnel-web spider keeps her babies in her web for about five weeks, bringing them insects to eat.

New research shows that personality impacts the roles played by spiders, at least in some species. Docile females are good mothers, caring for the young. More aggressive spiders mend webs, catch prey, defend the colony, and sometimes kill their own young. See a report on this research at http://www.csmonitor.com/Science/2014/0617/Spiders-divide-labor-by-personality-say-scientists-video.

12- In Mexico there are spider ranches. They raise Mexican red-kneed tarantulas and other arachnids to be sold as pets.

13- The word arachnophobia refers to a fear of spiders and other members of the arachnid family (scorpions, mites, ticks, etc.). The words “arachnid” and “arachnophobia” come from the name Arachne. According to Greek mythology, Arachne bragged a bit too much about her weaving ability, proclaiming that her tapestries were better even than those of the goddess Athena. Athena took up the challenge, setting up a contest to prove her superiority. Athena’s tapestry highlighted her victory over the sea god, Poseidon. Arachne used hers to poke fun at the gods. Athena angrily destroyed Arachne’s work, and turned her into a spider, decreeing that she would spend eternity weaving.

E. B. White created Charlotte, who may be the most famous spider in American literature. In the children’s novel, Charlotte’s Web, she manages to save the life of a pig named Wilbur, who had been the runt of the litter. But you probably already knew that!

If you want to learn more about spiders, stop by Fountaindale Library in Bolingbrook. Here are three books I used in preparing this blog post:

1-Stephen Dalton, Spiders: The Ultimate Predators (Firefly Books, 2008).

2-James Emerton, The Common Spiders of the United States (Dover Publications, 1061).

3-Rebecca Stefoff, The Arachnid Class (Marshall Cavendish Benchmark, 2009). (Junior non-fiction)

Fountaindale Library also has copies of Charlotte’s Web by E. B. White and DVD’s of the movie based on the book.

© Wilda Morris