Mexico's Pleistocene terrestrial mammal record includes 13 orders, 44 families, 147 genera and 280 species, thus is comparable to the Recent one, but shows greater ordinal and family diversity. Post-Pleistocene extinction chiefly involved meso- and megabaric species. The mammal, palynologic and paleosol records are strongly time and space biased in favor of Late Rancholabrean data from a few morphotectonic provinces; hence, only broad climatic trends could be delineated, which approximately coincide with those known for the Wisconsinan; they disclose by 25-12 ka, greater moisture and cooler temperature conditions than at present, coinciding too with a larger mammalian diversity and local faunas disharmony. Climate fluctuations impacted the fauna, causing species distribution changes and extinctions. The Recent fauna's complex biogeographic pattern reflects this; it includes tropical and temperate species associations outside their respective latitudes. Combining geologic and Recent mammal distribution data with the Pleistocene record, possible dispersal routes were detected: high and low land, southward corridors for temperate species, and low land, northward ones for tropical species. Finally, the existence of a single Mexican Rancholabrean Faunal Province is incompatible with mammal record's makeup and distribution, which calls for a multiprovince scheme to better understand Mexico's Pleistocene mammal biogeography and faunistics.