This is Scientific Americans 60 Second Science.

I'm Steve Mursky.

By now you may have heard about a study that came out a couple of weeks ago about spiders.

The study got a lot of attention because coverage of the research

often focused on the idea that spiders could eat every single person on the

planet in a year and still find room for a lot of cows and elephants and such. In other words, spiders need a lot of meat.

Fortunately, the food of choice for the overwhelming majority of spiders is other arthropods, mostly insects and another type of tiny critter called springtails.

Anyway, the study which never mentioned spiders eating all the world's people was done by Martin Nifelur at the University of

Basel in Switzerland and Klaus Berghofer of Lund University and Germany's Brandenburg University

of Technology, places with plenty of spiders, because most places

are places with plenty of spiders.

The right up in the April issue of the

issue concluded that the world spider population weighs some 25 million tons.

Your average spider only weighs an ity bit

so if you do the calculation you get a total worldwide population of some

11 to gazillion spiders more or less. But the 25 million tons of spiders is a real number

derived from other published studies dating as far back as 1951.

The researchers then estimated how much weight in food that much weight of spiders would

need, and they also went through many other studies

that had estimated how much spiders ate in particular habitats ranging from

tropical forests to farms. Once they crunched all those arthropods, the intrepid spider speculators reached their verdict.

Spiders snatched between 400 million and 800 million tons of meat annually. So if you see a spider and there's almost

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