ISSN:
1572-9753
Keywords:
dispersal
;
species abundance
;
xerothermic habitat
;
Stenobothrus lineatus
;
Stenobothrus stigmaticus
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Nature of Science, Research, Systems of Higher Education, Museum Science
Notes:
Abstract Two congeneric species of grasshopper, Stenobothrus lineatus and S. stigmaticus, are compared in an analysis of genetic structure relative to their observed mobility, and to the spatial structure of their habitat networks. The species differ in their habitat requirements, the latter being rarer and more restricted to isolated patches. We tested for different patch connectivity between the two species in an analysis of genetic variance (based on allozymes) under the assumption that, besides isolation, rarity influences the genetic parameters. Between the species we found no differences in genetic structure as estimated by FST; i.e., no isolation effects and no apparent differences between the species in the potential to move between habitat fragments on either a local or regional scale were found. However, the amount of genetic variation in the more widely distributed and less xerothermic S. lineatus was significantly higher than in S. stigmaticus. Some consistency with observed philopatry within patches was found (FIS 〉 0), but we consider regular dispersal events of medium and especially long distance to cause the habitat linking. We conclude that the connectivity between occupied patches inferred by genetic analyses can seldom be derived from low observed life-time movements recorded by conventional marking studies. Consequences of applying observed relative to indirect dispersal estimates for the examination of grasshopper metapopulations are discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1009695612760
