STANFORD, Calif., May 26 (UPI) — U.S. scientists say they’ve determined small mammals — and rest of food chain — are at a greater risk from global warming than has been thought.
Stanford University researchers say they’ve found the balance of biodiversity within North American small-mammal communities is so “out of whack” from the last episode of global warming about 12,000 years ago that the current climate change could push them past a tipping point — with repercussions all along the food chain.
The Stanford biologists said their evidence lies in fossils spanning the last 20,000 years that they excavated from a cave in Northern California.
They said although small mammals in the area suffered no extinctions as a result of the warming that occurred at the end of the Pleistocene epoch, populations of most species nonetheless experienced a significant loss of numbers and one highly adaptable species — the deer mouse — thrived on the disruptions to the environment triggered by the changing climate.
“If we only focus on extinction, we are not getting the whole story,” said Jessica Blois, lead author of the study. “There was a 30 percent decline in biodiversity due to other types of changes in the small-mammal community.”
The study, led by Professor Elizabeth Hadly, is reported in the early online edition of the journal Nature.
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