Pesticide Poisons Spiders, Makes Them Lazy Drunks

It's not exactly an uncommon sentiment to believe that pesticides are causing a lot more environmental harm than big chemical lets on. After all, some of the most popular pesticides in agriculture, neonicotinoids, have turned out to be a driving force behind pollinator decline around the world. Now new research has revealed that the harm doest stop there. According to new research, common insecticide sprays can actually alter a spider's personality, making them exceptionally lazy.

That's at least according to a study recently published in the journal Functional Ecology, which details how pesticides have a much more insidious effect on local ecology than experts ever imagined.

"Bronze jumping spiders play an important role in orchards and fields, especially at the beginning of the agricultural season, by eating many of the pests like the oblique-banded leafroller, a moth that attacks young plants and fruit," Raphaël Royauté, who led the research, said in a statement.

"Farmers spray insecticides on the plants to get rid of these same pests, and it was thought that it had little significant effect on the spiders' behaviors," he explained. "But we now know that this isn't the case." (Scroll to read on...)

But wait a second... Spiders have personalities? As it turns out, a lot of bugs have what you could call personality, and spiders are no exception. Nature World News has previously reported how most spiders are either timid or aggressive and these traits vary even among members of the same species. As a result, some highly social spiders like Anelosimus studiosus even go as far as to assign jobs based on these traits. Aggressive females, for instance, are assigned the role of body guard even while their gentler counterparts are given the honor of raising a colony's young.

In this latest study, Royauté and his colleague determined that among bronze jumping spiders, these traits also influence hunting behavior.

"Some individuals are willing to take risks when predators are present, explore new territories faster, or capture prey more quickly," the researcher said. "But the effects of insecticides on personality types remains poorly described." (Scroll to read on...)

Spiders are Lazy Drunks

Specifically, Royauté and his colleagues assessed personality and behavior of these spiders before and after exposure to common agriculture pesticide (organophosphate insecticide phosmet). As a result, the researchers describe how the behavior of affected spiders became increasingly unpredictable - a phenomenon Royauté likens to having one too many at a bar.

"We know that drinking alcohol can make us act in weird ways, by removing some social inhibitions for example," he said in a statement. "So one of the primary question of my research became: can insecticides cause similar personality shifts in individual spiders?"

His answer was a resounding 'yes,' with many of the affected spiders growing 'lazier' than they once were - taking fewer risks and exploring very little. And just like alcohol with people, the effects of this 'drunkenness' varied with each individual, with females as-a-rule proving more vulnerable. This may be in-part due to the fact that mature male jumping spiders often outweigh females - a rarity among spiders - meaning it will take more toxin to affect them. However, the exact biological nature of the toxin's influence still needs to be investigated.

"By looking at the way that insecticides affect individual spider behaviors, rather than averaging out the effects on the spider population as a whole, as is traditionally done in scientific research, we are able to see some significant effects that we might have otherwise missed," added Chris Buddle, who co-authored the paper. "It means we can measure the effects of insecticides before any effects on the spider population as a whole are detected, and in this case, it's raising some red flags."

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