ScienceFossils from La Brea Tar Pits show climate change drove evolution of ice age predators Fossils from the La Brea Tar Pits in Los Angeles show climate's effect on ancient saber-toothed cats and huge, ferocious wolves. What really happened?by Jim Algar
ScienceModern day carnivorous mammals' early ancestor was a tree dwelling, squirrel-like creatureby Maryanne Moll