Clonal diversity in high arctic ostracodes

• Published in: Journal of Evolutionary Biology
• Main Authors: Little, T. J., Hebert, P. D. N.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Oxford University Press (OUP) 1997
• Subjects: Ecology, Evolution, Behavior and Systematics; Arctic; Igloolik
• Online Access: http://dx.doi.org/10.1046/j.1420-9101.1997.10020233.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1420-9101.1997.10020233.x; https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1420-9101.1997.10020233.x

Abstract It remains unclear why the majority of parthenogenetic lineages persist for only brief periods of evolutionary time. However, by characterizing their patterns of genetic variation, it is possible to gain insights regarding their evolutionary origin and potential. We examined clonal diversity patterns in high arctic populations of freshwater ostracodes with the goal of clarifying the factors promoting genotypic diversity. Allozyme electrophoresis showed that the three dominant ostracode species in high arctic ponds reproduce via apomictic parthenogenesis that two of these species ( Prionocypris glacialis, Candona rectangulata ) were both highly clonally diverse, and had allozyme phenotypes suggestive of polyploidy. Scanning microdensitometry confirmed that many clones of P. glacialis at Igloolik were polyploid. In contrast to most other polyploids, clones of P. glacialis seem to be autopolyploids. Although clonal variation in P. glacialis may reflect multiple transitions to parthenogenesis in an undetected sexual population, it seems likely that genomic recombination associated with polyploidy has also played a role in generating local diversity following the transition to parthenogenesis.