Animals will eat each other in the struggle for resources.
Living in the Arctic spiders Pardosa lapponica can become cannibals if their population will increase substantially.
To such conclusion the American scientists in article published in the Journal of Animal Ecology.
Biologists have studied the behavior of female spiders for one summer in Alaska. As with global warming, Arctic summer lasts longer, the spiders have now more favorable conditions for reproduction. In the future their number will increase, scientists predict.
But in the fight for food the spiders will sooner or later begin to do to adjust the size of the population, eating competitors. Therefore, to adulthood living out only a small percentage.
Using isotope analysis, researchers from Washington University in Saint Louis analyzed the diet of female spiders. He showed that a pathological shift in the diet towards cannibalism occurred after the increase of population density.
But the study also showed that the spiders are cannibals live shorter lives than their relatives with more usual diet.
Anna Lysenko
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