The influence of habitatsize on clonal diversity within populations and on genetic differentiation among populations, in a cyclical parthenogen: Daphnia magna
Vanoverbeke, J.; De Meester, L. (1998). The influence of habitatsize on clonal diversity within populations and on genetic differentiation among populations, in a cyclical parthenogen: Daphnia magna. Biol. Jb. Dodonaea 65: 197 In: Biologisch Jaarboek (Dodonaea). Koninklijk Natuurwetenschappelijk Genootschap Dodonaea: Gent. ISSN 0366-0818, more Also appears in:Beeckman, T.; Caemelbeke, K. (Ed.) (1998). Populations: Natural and manipulated, symposium organized by the Royal Society of Natural Sciences Dodonaea, University of Gent, 29 October 1997. Biologisch Jaarboek (Dodonaea), 65. Koninklijk Natuurwetenschappelijk Genootschap Dodonaea: Gent. 257 pp., more |
| Keywords | Biology > Genetics > Population genetics
Conferences
Habitat
Daphnia magna Straus, 1820 [WoRMS]
Fresh water |
| Abstract | During favourable conditions Daphnia reproduce parthenogenetical1y with the formation of clones. Using al1ozyme electrophoresis, we analysed the clonal structure of several natural Daphnia magna populations. Surface area of the ponds was used as a measure of habitat size and ranged from a few square meters to more than 80 ha. In general, smal1er ponds tended to have a lower clonal diversity than larger ponds. Larger ponds might indeed be expected to contain a higher diversity of microhabitats, in which differently adapted clones may survive. Furtherrnore, larger ponds wil1 include larger populations and a larger stock of resting eggs. Both a larger population size and a higher recruitment from the resting eggs wil1 slow down clonal erosion after a period of selection. When we plot genetic differentiation between populations against surface area of the habitats, a negative correlation is observed. In previous work we showed that, in cyclical parthenogenetic Daphnia, the genetic differentiation as revealed by (quasi-) neutral al1ozymes, is to a great extent determined by the clonal diversity of the populations. Populations with a smal1 clonal diversity wil1 tend to be more genetically differentiated from other populations than populations with a high clonal diversity. This is due to the enhancement of driftlike phenomenons in populations where the clonal diversity is low. As the smal1er populations, in general, have a lower clonal diversity, they indeed might be expected to be more genetical1y differentiated from other populations than the larger ones. |
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