Spiders Under the Influence: What Effects Do Drugs Have on Animals and Insects?

Most people know fairly well the effects that certain types of drugs have on human behavior and habits. Alcohol makes people louder, more confident and sometimes even aggressive. Cannabis makes people relaxed, more creative, deepens the flow of thoughts and sometimes causes paranoia. Caffeine is known to have a stimulating effect and causes students and workers to stay on task. That’s all well and good, but have you ever wondered what effect these drugs have on animals? Or on spiders, to be exact? As strange as it may seem, studies have been conducted that determined the effects of certain drugs on the behavior of spiders. Scientists observed how certain drugs caused spiders to construct their webs abnormally. Below are some insights into the origins of these studies and the conclusions scientists drew from them.


In the year 1948, a man named Hans Peters conducted perhaps the very first study in which spiders were administered drugs. Peters, who happened to be a zoologist, wanted to make a documentary that would show how spiders weaved their webs. He ran into a problem, however, It turned out that spiders have a habit of weaving their webs at less desirable hours of the day. To break that problem Peters used sugar water with certain drugs in the hope that this would cause the spiders to build their webs at a different time of day. Peters asked his colleague and pharmacologist Peter Witt to make the concoctions with the drugs. Witt got to work adding a range of drugs to various amounts of sugar water including cannabis, LSD, morphine, peyote, amphetamine and scopolamine. Despite administering such a variety of drugs to different spiders, the critters continued to weave their webs in the dead of night even as they were, by all accounts, quite under the influence of all those hallucinogenic drugs. However, it was observed that the spiders constructed their webs with a different pattern depending on which drug they were administered. Curious by these results, Witt decided to conduct further research on the subject which included the use of caffeine.


After studying spiders for some time, Witt decided to focus primarily on a type of garden spider that weaves a spherical web. He found that caffeine caused spiders to weave a smaller web, while cannabis resulted in spiders being distracted and not paying attention to the inner structure of their web. Scopolamine, on the other hand, caused spiders to lose their sense of direction. A small dose of LSD seemed to encourage spiders to simply weave functional and well-designed webs. Witt’s results ultimately concluded that various drugs did indeed change the behavior of spiders.


In 1995, NASA decided to replicate Witt’s research. But they went a step further, using computer technology to determine the differences of the structure of the webs, in order to determine the degree of toxicity. During these studies, the spiders were administered cannabis, sleeping pills, amphetamine and caffeine. European garden spiders were chosen to do the job. The scientists found that the more toxic substances resulted in the spider webs looking more disturbed. The spiders under the influence of cannabis looked a little strange but they still looked like a normal web. The web under the influence of amphetamines was irregular but still manageable. However, the webs woven on caffeine and sleeping pills looked quite messy and chaotic.