Genetic diversity and origin of two Queen Charlotte Islands plants: Senecio newcombei and Saxifraga taylori

• Main Author: Goertzen, Leslie R.
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/4562

Questions concerning the history and origins of two vascular plants endemic to the Queen Charlotte Islands, Senecio newcombei and Saxifraga taylori, are examined from a biosystematic and population genetics standpoint. Both species maintain levels of genetic variation lower than would be expected from their breeding system and geographic range. Historical factors such as population bottlenecks and founder events may have contributed to the genetic profiles of these species, a suggestion consistent with their hypothesized survival in Pleistocene glacial refugia. The allozyme variability of a third species, Saxifraga vespertina, was assessed to compare its genetic complement to S. taylori. Although complicated by an overall lack of variation, a low estimation (0.224) of Nei's genetic identity does not support the hypothesis of a historically recent divergence of the two species. ii