For loan of specimens and tissues relevant to this study, we thank R. S. Voss and E. Westwig (AMNH), B. D. Patterson and W. Stanley (FMNH), M. S. Hafner (LSUMZ), J. L. Patton and C. Cicero (Museum of Vertebrate Zoology, Berkeley), and R. J. Baker and H. Garner (Natural Science Research Laboratory, Texas Tech University, Lubbock). All molecular analyses were completed during the graduate studies of Solari at Texas Tech University, under guidance of R. J. Baker; we express our gratitude for facilitating use of the molecular lab. A. L. Gardner and D. E. Wilson (USNM) supported Solari during his visit to Washington, D.C. Support was provided by Texas Tech through a J. Knox Jones Memorial Fund (2004) and a Cash Family Endowment (2006). Solari was also supported by an Albert R. and Alma Shad le Fellowship (2005) and an ASM Fellowship (2006) from the American Society of Mammalogists. Figure 4 w...