This is Scientific American 60 Second Science. I'm Suzanne Bard.

Some scientists stick to the lab, but others brave venomous snakes and down power lines. Take Jonathan Pruitt, an evolutionary

biologist at McMaster University. During last year's hurricane season he went to the

U.S. Southeast to see how extreme weather affects spiders.

The goal of this experiment was basically to figure out how rare but extreme events might sculpt the traits of animals that we see out there in the wild.

The inherent difficulties in doing this kind of work has meant little research into how

disasters can be a driving force behind natural selection.

The only way that I was able to do this was via the assistance of locals who immediately following these

storms all get into their trucks and drive around to survey the damage of their houses, but they also bring chainsaws.

And so they will be cutting their way through state roads.

And I basically just draft right behind what could be a Conga line of F-150s with chainsaws and use them to cut a path back to my study sites.

All that to survey the habits of Tanglewebs spiders, which live in colonies above bodies of water.

And they cooperate into doing prey together like a time. live in colonies above bodies of water.

And they cooperate in doing prey together

like a tiny spidery pride of lions.

The spiders come in two personality types,

docile and aggressive.

Aggressive colonies are prone to cannibalism, fight among themselves, and are quick to pounce on their prey.

Pruitt found that when aggressive colonies survived a storm, they produced more baby spiders than did their less aggressive

counterparts. But in hurricane-free areas, docile colonies had more babies.

So whether or not it's good to be an aggressive society is contingent on whether or not you're going to have a tropical cyclone strike to you or are not that year.

Pruitt thinks the difference is due to hurricanes lowering the number of insect prey flying around. He says of the aggressive spiders,

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