This paper examines the relation between chromosomal and nuclear-gene divergence in 28 wild populations of the house mouse semi-species, Mus musculus domesticus, in Western Europe and North Africa. Besides describing the karyotypes of 15 of these populations and comparing them to those of 13 populations for which such information was already known, it reports the results of an electrophoretic survey of proteins encoded by 34 nuclear loci in all 28 populations. Karyotypic variation in this taxon involves only centric (or Robertsonian) fusions which often differ in arm combination and number between chromosomal races. The electrophoretic analysis showed that the amount of genie variation within Robertsonian (Rb) populations was similar to that for allacrocentric populations, i.e. bearing the standard karyotype. Moreover, divergence between the two types of populations was extremely low. These results imply that centric fusions in mice have not modified either the level or the nature of genie variability. The genetic similarity between Rb and all-acrocentric populations is not attributed to the persistence of gene flow, since multiple fusions cause marked reproductive isolation. Rather, we attribute this extreme similarity to the very recent origin of chromosomal races in Europe. Furthermore, genie diversity measures suggest that geographically separated Rb populations have in situ and independent origins. Thus, Rb translocations are probably not unique events, but originated repeatedly. Two models are presented to explain how the rapid fixation of a series of chromosomal rearrangements can occur in a population without lowering variability in the nuclear genes. The first model assumes that chromosomal mutation rates are between 10~3 and 10~4 and that populations underwent a series of transient bottlenecks in which the effective population size did not fall below 35. In the second model, genie variability is restored following severe bottlenecks, through gene flow and recombination.

The Mound-building mouse Mus spicilegus possesses a unique behaviour amongst mice. It constructs large earthen mounds and associated nesting chambers which serve to store food for immature individuals during the winter nesting period. We have used genetic analysis of four autosomal and four X-linked microsatellite loci to determine relationships between individuals inhabiting 40 mounds in Bulgaria. We show that, in almost all cases, individuals in a mound are the product of multiple parentage. We estimate the minimum number of males and female parents contributing offspring to each mound and demonstrate that at least two male and two female parents contribute offspring to a minimum of seven mounds. Analyses of relatedness coefficients and allele sharing values demonstrate that parents of different sibships within mounds are more related than if they had been chosen at random from the population and suggest that it is the female parents that contribute this excess relatedness. These results suggest that the mechanism by which individuals congregate to build mounds is kin-based and that the evolution of mound building and communal nesting in M. spicilegus is due in part to kin selection. This study represents a novel approach to the study of mammalian behavioural ecology. We have used a genetic dataset to construct an outline of social structure in the absence of behavioural data. These inferences can now be used to direct further work on this species.

Annales de Parasitologie (Paris)1978, t. 53, n° 6, pp. 711-749. Les Phlébotomes de Tunisie Résumé.Les auteurs présentent une révision systématique, chorologique et éthologique des Phlé botomes de Tunisie. Une clé dichotomique des 15 taxums observés est proposée. Un essai de synthèse biogéographique met en évidence la liaison entre les foyers de leishmaniose viscérale et les zones couvertes par les représentants du sous-genre Larroussius. Summary.The phlebotomines of Tunisia (Diptera-Phlebotominae). A revision of the systematics, distribution and behaviour.The authors present a revision of the systematics, distribution and ethology of the phlebotomine sandflies of Tunisia. They present a dichotomous key for 15 taxa. A biogeographical analysis shows the connexion between foci of visceral leishmaniasis and the zones of distribution of the subgenus Larroussius.