applyparastyle "fig//caption/p[1]" parastyle "FigCapt" applyparastyle "fig" parastyle "Figure" Journal of Mammalogy, 100(5):1546–1563, 2019 DOI:10.1093/jmammal/gyz128 Downloaded from https://academic.oup.com/jmammal/article-abstract/100/5/1546/5571357 by University of California School Law (Boalt Hall) user on 22 October 2019 Geographic variation and evolutionary history of Dipodomys nitratoides (Rodentia: Heteromyidae), a species in severe decline James L. Patton,* Daniel F. Williams, Patrick A. Kelly, Brian L. Cypher, and Scott E. Phillips Museum of Vertebrate Zoology, University of California, 3101 Valley Life Sciences Building, Berkeley, CA 94720, USA (JLP) California State University, Stanislaus, Endangered Species Recovery Program, Department of Biological Sciences, 1 University Circle, Turlock, CA 95382, USA (DFW, PAK, BLC, SEP) * Correspondent:
[email protected] We examined geographic patterns of diversification in the highly impacted San Joaquin kangaroo rat,Dipodomys nitratoides, throughout its range in the San Joaquin Valley and adjacent basins in central California. The currently recognized subspecies were distinct by the original set of mensural and color variables used in their formal diagnoses, although the Fresno kangaroo rat (D. n. exilis) is the most strongly differentiated with sharp steps in character clines relative to the adjacent Tipton (D. n. nitratoides) and short-nosed (D. n. brevinasus) races. The latter two grade more smoothly into one another but still exhibit independent, and different, character clines within themselves. At the molecular level, as delineated by mtDNA cytochrome b sequences, most population samples retain high levels of diversity despite significant retraction in the species range and severe fragmentation of local populations in recent decades due primarily to landscape conversion for agriculture and secondarily to increased urbanization.