1948, University of Tubingen, Germany.
Zoologist H. M. Peters was frustrated. He was conducting a photographic research on the way orb-weaver spiders build their web, but he had encountered a problem: the arachnids he was studying insisted on performing this task of astounding engineering only during the night hours, very early in the morning. This schedule, besides forcing him to get up at an ungodly hour, made photographic documentation quite hard, as the spiders preferred to move in total darkness.
One day Peters decided to call on a collegue, young pharmacologist Dr. Peter N. Witt, for assistance. Would it be possible to somehow drug the spiders, so they would change this routine and start weaving their webs when the sun was already up?
Witt had never had any experience with spiders, but he soon realized that administering tranquilizers or stimulants to the arachnids was easier than he thought: the little critters, constantly thirsty for water, quickly learned to drink from his syringe.
The results of this experiment, alas, turned out to be pretty worthless to zoologist Peters. The spiders kept on building their webs during the night, but that was not the worst part of it. After swallowing the medicine, they weren’t even able to weave a decent web: as if they were drunk, the arachnids produced a twisted mesh, unworthy of being photographed.
After this experience, a disheartened Peters abandoned his project.
In Dr. Witt’s mind, instead, something had clicked.
Common spiders (Araneidae) are all but “common” when it comes to weaving. They build a new web every morning, and if byt he end of the day no insect is trapped, they simply eat it. This way, they are able to recycle silk proteins for weeks: during the first 16 days without food, the webs look perfect. Whe nthe spider gets really hungry, it begins sparing the energy by building a wider-meshes web, suitable to catch only larger insects (the spider is in need of a substantial meal).
After all, for a spider the web isn’t just a way to gather food, but an essential instrument to relate with the surrounding world. Most of these arachnids are almost totally blind, and they use the vibrations of the strands like a radar: from the perceived movements they can understand what kind of insect just snagged itself on the web, and if it is safe for them to approach it; they can notice if even a single thread has broken, and they confidently head in the right direction to repair it; they furthermore use the web as a means of communication in mating rituals, where the male spider remains on the outer edges and rythmically pinches the strings to inform the female of its presence, in order to seduce her without being mistaken for a juicy snack.
During his experimentation with chemicals, Dr. Witt noticed that there seemed to be a significative correspondence between the administered substance and the aberrations that the spiderweb showed. He therefore began feeding the spiders different psychoactive drugs, and registering the variations in their weaving patterns.
Dr. Witt’s study, published in 1951 and revised in 1971, was limited to statistical observation, without attempting to provide further interpretations. Yet the results could lead to a fascinating if not very orthodox reading: it looked like the spiders were affected in much the same way humans react to drugs.
Under the influence of weed, they started regularly building their web, but were soon losing interest once they got to the outer rings; while on peyote or magic mushrooms, the arachnids movements became slower and heavier; after being microdosed with LSD, the web’s design became geometrically perfect (not unlike the kaleidoscopic visions reported by human users), while more massive doses completely inhibited the spiders’ abilities; lastly, caffeine produced out of control, schizoid results.

Spiderweb after high doses of LSD-25.
Clearly this “humanized” interpretation is not scientific to say the least. In fact, what really interested Witt was the possibility of using spiders to ascertain the presence of drugs in human blood or urine, as they had proved sensitive to minimal concentrations, which could not be instrumentally detected at the time. His research continued for decades, and Witt went from being a pharmacologist to being an entomology authority. He was able to recognize his little spliders one by one just by looking at their webs, and his fascination for these invertebrates never faded.
He kept on testing their skills in several other experiments, by altering their nervous system through laser stimulation, administering huge quantities of barbiturics, and even sending them in orbit. Even in the absence of gravity, in what Witt called “a masterpiece in adaptation”, after just three days in space the spiders were able to build a nearly perfect web.
Near the end of the Seventies, Witt discontinued his research. In 1984 J. A. Nathanson re-examined Witt’s data, but only in relation to the effects of caffeine.
In 1995 Witt saw his study come back to life when NASA successfully repeated it, with the help of statistic analysis software: the research showed that spiders could be used to test the toxicity of various chemicals instead of mice, a procedure that could save time and money.
Anyway, there is not much to worry regarding the fate of these invertebrates.
Spiders are among the very few animals who survived the biggest mass extinction that ever took place, and they are able to resist to atmospheric conditions which would be intolerable to the majority of insects. Real rulers of the world since millions of years, they will still be here a long time — even after our species has run its course.
Loro e gli scarafaggi…Degni eredi della nostra prosopopea !!!
😀
mi sei mancato! un articolo veramente interessante! 😀
Eh… periodo un po’ faticoso, ho avuto poco tempo di aggiornare. 🙂
Interessantissimo 😉
Articolo molto interessante 🙂 Un po’ di tempo fa mi ero già imbattuto nell’argomento con questo video che avevo trovato su youtube
https://www.youtube.com/watch?v=4m0kO30m00Y
Articolo molto interessante e di piacevole lettura. Complimenti.
Ti ringrazio.