redOrbit: A new University of Florida study indicates extinct carnivorous mammals shrank in size during a global warming event that occurred 55 million years ago. The study, scheduled to appear in the December print edition of the Journal of Mammalian Evolution and now available online, describes a new species that evolved to half the size of its ancestors during this period of global warming. The hyena-like animal, Palaeonictis wingi, evolved from the size of a bear to the size of a …