, Volume 85, Issue 2, pp 163–179 | Cite as

Genome evolution in pocket gophers (genus Thomomys)

II. Variation in cellular DNA content
  • Steven W. Sherwood
  • James L. Patton


Cellular DNA content (2 C-value) was measured by fluorescence flow cytometry of chromomycin-A3 stained spleen cells in 2 subgenera, 5 species, and 21 subspecies of pocket gophers (genus Thomomys). The data indicate that, in Thomomys: (1) interspecific variation is extensive but, while some congeneric species differ by as much as 230%, others are identical in C-value; (2) intraspecific differentiation can be extensive with C-values differing by as much as 35%; and (3) populations of the same subspecies with apparently similar karyotypes can differ significantly in C-value. The implications of these results for hypotheses of the “adaptive” significance of C-value variation and genome evolution are discussed.


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Copyright information

© Springer-Verlag 1982

Authors and Affiliations

  • Steven W. Sherwood
    • 1
  • James L. Patton
    • 1
  1. 1.Museum of Vertebrate ZoologyUniversity of CaliforniaBerkeleyUSA

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