With funding from the National Science Foundation, the research team traveled to bogs in British Columbia, Quebec City, and Georgiathe full extent of the plant's rangeto analyze the aquatic food webs from 60 pitcher plants. They found 35 different types of organisms inside, with a large contingent of bacteria counting as just one type. Then, says Baiser, "We wanted to know: how did we get different food webs in individual pitchers from the same species pool? What caused these food webs to form the way they did?"
A few well-established scientific models predict how food webs form based on a ranked system of ecosystem factors. For the Oikos study, Baiser and his team checked their real-world observations against those models. He explains: "Say you've got a bunch of lakes. And you've got a big bucket holding all the species that can live in those lakes. When you dump out the bucket, which creatures end up in which lake? What matters more: the size of the lake, or the fact that predator species X is there, too? Or is it random? Those models help us tease those factors apart."
According to the Oikos study, the way pitcher plant food webs assemble is not random. In fact, it seems the predator-prey interactions are of key importance. "You take out one species, and that affects everything else," says Baiser.
|Contact: Clarisse Hart|