United Press International: Global warming may be the reason for a decrease in the number of caribou calves being born in West Greenland, U.S. researchers said. Biologist Eric Post said data show the timing of peak food availability no longer corresponds to the timing of caribou births, the university said Friday in release. The study, conducted in collaboration with Mads Forchhammer at the University of Aarhus in Denmark, will be published in the July issue of the Philosophical Transactions of the Royal …