Subspeciation in the Meadow Mouse, Microtus pennsylvanicus, in Wyoming, Colorado, and Adjacent Areas

"Subspeciation in the Meadow Mouse, Microtus pennsylvanicus, in Wyoming, Colorado, and Adjacent Areas" by Sydney Anderson is a mid-twentieth-century scientific exploration that looks closely at the different types of meadow mice in Wyoming and Colorado. The publication examines the physical differences among these subspecies, mapping out where each lives and detailing how geography affects their distribution. Based on studying 762 specimens, three new subspecies are distinguished through comparing skull sizes, color variations, and other unique physical features, revealing the important role of local environments in shaping the evolution of these small animals.