Genetic Variability in Natural Populations of the Moss Atrichum angustatum

An electrophoretic survey of the moss Atrichum angustatum (Brid.) B.S.G. showed varying degrees of staining activity for eight of the ten specific enzymes surveyed. Of the eight active systems, four were scoreable: acid phos- phatase, glutamate dehydrogenase, malate dehydrogenase and phosphoglucoisom- erase. Comparisons of 15 populations of A. angustatum utilizing these four enzyme systems indicated significant levels of genetic variability both within and among populations. The traditional view of bryophytes as genetically impoverished or- ganisms with severely limited potential for response to natural selection is chal- lenged by these results.