Predator Numbers Don't Always Increase with Prey

Scientists have uncovered what seems to be an unusual law of nature that keeps big predator numbers low across vast spaces of the Earth and its oceans. Even when there are plenty of prey around for larger creatures like lions to eat, the number of lions in an area does not increase, said the findings in the journal Science. It's all a form of camouflage, right? Wrong! Trace takes a look at a few different animals in the wild that have prominent features with a weird purpose.    The same pattern holds just as true for big animals as it does for tiny sea creatures like zooplankton, which eat phytoplankton. "Where prey are abundant, there are not proportionally more predators," said the study, which analyzed data going back 50 years on plants and animals across 2,260 ecosystems in 1,512 distinct locations worldwide, including grasslands, lakes, forests and oceans. Rather than predators rising in number to match the available prey, predator populations are limited by the rate at which prey reproduce. And in crowded settings, prey reproduced less than they did in settings where there were fewer prey around, suggesting that competition for resources may be working to limit prey offspring. Continue Reading: http://news.discovery.com/animals/endangered-species/predator-numbers-dont-always-increase-with-prey-150906.htm