Content area
Full Text
Hydrobiologia (2012) 689:3749 DOI 10.1007/s10750-011-0741-1
POND RESEARCH AND MANAGEMENT
Colonization in action: genetic characteristics of Daphnia magna Strauss (Crustacea, Anomopoda) in two recently restored ponds
Raquel Ortells Carla Olmo Xavier Armengol
Received: 22 October 2010 / Accepted: 4 May 2011 / Published online: 18 May 2011 Springer Science+Business Media B.V. 2011
Abstract New habitats are an interesting tool to monitor colonization processes in the light of changes in genetic structure and evolutionary potential of populations. Cladocerans are cyclical parthenogens that offer the possibility to track genetic changes during the colonization process due to the alternation of sexual and asexual phases. The locally called malladas are shallow and temporary peridunal ponds in Eastern Spain that were silted in the 1960s and have been recently dug to their original basin. We here describe the colonization process in two of these newly restored ponds by the cladoceran Daphnia magna during their rst 3 years. This colonization process followed three critical steps: population founding by the initial colonists, arrival of secondary immigrants and consolidation of the population
structure. We found a low number of genotype colonists followed by the establishment of secondary immigrants and a slight decrease in gene ow with time. We discuss the importance of dispersal, founder effects, natural selection, inbreeding depression and genetic drift during the colonization process in the light of the most recent literature.
Keywords Genetic differentiation Inbreeding
depression Monopolization Hypothesis
Zooplankton
Introduction
Dispersal and colonization are processes that affect biological and genetic diversity (Bilton et al., 2001; Bohonak & Jenkins, 2003). From an ecological perspective, dispersal and hatching rates, priority effects, species sorting and biotic interactions can be crucial to understand the dynamics and composition of zooplankton communities (Morin, 1999). Additionally, a population genetic approach offers the possibility to study simultaneously analogous processes such as colonization by genotypes, founder effects, natural selection and interactions among clones. Newly created habitats represent a unique opportunity to study such processes as they are monitored from the moment of population founding thus avoiding confounding historical events. For example, much of the structure in genetic variation
Guest editors: D. Boix, B. Oertli, R. Crghino, T. Kalettka,J. Biggs & A. P. Hull / Pond Research and Management in Europe Proceedings of the 4th conference of the European Pond Conservation...