It is argued that for marine organisms the genetic signatures of northern periglacial and southern refugia can be distinguished from one another, giving credence to recent climatic reconstructions with less extensive glaciation.
Blue mussels representing two nominal species were collected from 28 intertidal locations along the Pacific coast of the USA in 1990–1991 and examined for variation at 15 allozyme loci, where salinity was found to have a greater influence than temperature on the microgeographic distribution of the two species.
A comprehensively sampled, three-gene molecular phylogenetic analysis of the Valvatacea is presented, suggesting that Antarctic valvataceans may be derived from sister taxa in adjacent regions.
A hypothesis of an older fauna present in the Antarctic during the Eocene, which was succeeded by a modern Antarctic fauna that is represented by the recently derived Antarctic Asteriidae and other forcipulatacean lineages is suggested.
The distribution of several recently inserted Alu family members within representatives of diverse human groups and the isolation and characterization of additional highly dimorphic AlU family members should provide a useful tool for human population genetics.
It is concluded that C. deitersi in North America is composed of at least four separate species by the genealogical concordance, phylogenetic, and morphological-species criteria.
The methods used in this paper have generality and could be used to study the mating system in other mammals that are difficult or impossible to study by direct observation, as well as several other probable cases of monogamy among small rodents.
The genetic control of 11 electrophoretically detected allozyme polymorphisms in the oysterCrassostrea virginica was investigated and there was no evidence that heterozygosity per se had an effect on viability of offspring within a cross.
Populations of several marine bivalves exhibit significant deficiencies of heterozygotes at some allozyme loci and the possibility that the deficiencies are due to the occurrence of null (nonreactive) alleles or to other factors causing allo enzyme loci to depart from a simple codominant model of genetic control is considered.