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• Main Authors: G. E. Ball, D. C. Currie
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Yukon; polar desert; Tundra; Beringia
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.456.5710; http://www.biology.ualberta.ca/bsc/pdf/ball.pdf

Abstract. The Yukon ground-beetle fauna is analyzed in terms of species composition, geographical distribution, Wisconsinan and early Holocene fossils, habitat associations, and patterns of hindwing development. This analysis provides the basis for an interpretation about the development of the extant ground-beetle fauna of the Yukon Territory. In total, 209 species or subspecies of ground beetles are recorded from the Yukon Territory, of which at least 98, representing 46 % of the extant ground-beetle fauna, are hypothesized to have been present in northwestern refugia during the Wisconsinan glaciation. This figure was derived from a combination of distributional and fossil evidence. The range of habitat associations exhibited by this autochthonous component suggests that the Beringian environment may have been more complex than suggested by the “mammoth steppe ” or “polar desert ” models. Our data are most consistent with the “mosaic model”, in which a variety of habitats are hypothesized to have persisted within Beringia. The fauna associated with tundra, riparian zones, and marshes provides evidence that such habitats probably existed in Beringia during late Wisconsinan time, whereas the fauna associated with forest, grassy meadow, and other habitats shows only limited evidence of a long history in northwestern North America. This latter group is hypothesized to have been derived primarily from refugia south of Wisconsinan-age ice. The high degree of endemism in present-day tundra environments indicates long-term stability of that habitat. Analysis of the pattern of hindwing development indicates that brachyptery is most prevalent among the Beringian endemic