Ever since Ernst Mayr (1942) called ring species the 'perfect demonstration of speciation', they have attracted much interest from researchers examining how two species evolve from one. In a ring species, two sympatric and reproductively isolated forms are connected by a long chain of intermediate populations that encircle a geographic barrier. Ring species have the potential to demonstrate tha...

Long-term studies of hybrid zones can provide valuable insight into a number of questions that have long attracted the attention of evolutionists. These questions range from the stability and fate of hybrid zones to the relative fitness of hybrids. In this paper we report the results of a 14-year survey of the Allonemobius fasciatus-Allonemobius socius hybrid zone. Populations were collected in...

Reproductive isolation between populations often evolves as a by-product of independent adaptation to new environments, but the selective pressures of these environments may be divergent ("ecological speciation" or uniform ("mutation-order speciation." In this study, we use an artificial life platform to directly compare the strength of reproductive isolation (specifically, postzygotic) generat...

The isolation-with-migration (IM) model is commonly used to make inferences about gene flow during speciation, using polymorphism data. However, it has been reported that the parameter estimates obtained by fitting the IM model are very sensitive to the model's assumptions-including the assumption of constant gene flow until the present. This article is concerned with the isolation-with-initial...

Theoretical and empirical research on the evolution of reproductive isolation have both indicated that the effects of sexual selection on speciation with gene flow are quite complex. As part of this special issue on the contributions of women to basic and applied evolutionary biology, I discuss my work on this question in the context of a broader assessment of the patterns of sexual selection t...

The article refers to the technique of biomagnetical separation (BS) of mRNA using "Dynabeads mRNA DIRECT". After a brief survey of RNA isolation methods authors describe a general procedure of BS as well as its concrete application for mRNA isolation from bronchoalveolar cells. Authors report results of specific experiments to assess the efficiency and accuracy of mRNA isolation by BS. The app...

Species are separated by reproductive isolation as well as by more 'ordinary' differences in morphology and behavior that play no necessary role in blocking gene flow. Although a great deal is now known about the genetics of reproductive isolation, we are only beginning to understand the genetic basis of ordinary phenotypic differences between species. I review what is known about the number of...

The extent of within-species genetic variation across the diversity of animal life is an underexplored problem in ecology and evolution. Although neutral genetic variation should scale positively with population size, mitochondrial diversity levels are believed to show little variation across animal species. Here, we report an unprecedented case of extreme mitochondrial diversity within natural...

Spore killers in fungi are selfish genetic elements that distort Mendelian segregation in their favor. It remains unclear how many species harbor them and how diverse their mechanisms are. Here, we discover two spore killers from a natural isolate of the fission yeast Schizosaccharomyces pombe. Both killers belong to the previously uncharacterized wtf gene family with 25 members in the referenc...

The aim of this study was isolation and identification fungi producing aflatoxin B1 from wheat which stored for four months in some silos Baghdad , including Al Taji Silo, Khan Bani Saad Silo Dhari Silo. Those Silos were included the agricultural plan marketing season 2020. Different types obtained. They initially identified according to cultural morphological characteristics as Alternaria spp,...