Phylogeography is experiencing a revolution brought on by next-generation sequencing methods. A historical survey of the phylogeographic literature suggests that phylogeography typically incorporates new questions, expanding on its classical domain, when new technologies offer novel or increased numbers of molecular markers. A variety of methods for subsampling genomic variation, including restriction site associated DNA sequencing (Rad-seq) and other next generation approaches, are proving exceptionally useful in helping to define major phylogeographic lineages within species as well as details of historical demography. Next-generation methods are also blurring the edges of phylogeography and related fields such as association mapping of loci under selection, and the emerging paradigm is one of simultaneously inferring both population history across geography and genomic targets of selection. However, recent examples, including some from our lab on Anolis lizards and songbirds, suggest that genome subsampling methods, while extremely powerful for the classical goals of phylogeography, may fail to allow phylogeography to fully achieve the goals of this new, expanded domain. Specifically, if genome-wide linkage disequilibrium is low, as is the case in many species with large population sizes, most genome subsampling methods will not sample densely enough to detect selected variants, or variants closely linked to them. We suggest that whole-genome resequencing methods will be essential for allowing phylogeographers to robustly identify loci involved in phenotypic divergence and speciation, while at the same time allowing free choice of molecular markers and further resolution of the demographic history of species.
s reality a ''Ready-Made World'' or an entity constructed by individuals and social activity? The concept of the environment seems to be the boundary that clearly shows how we can simultaneously adhere to our apparently contradictory intuitions— that is, those about the external and autonomous features of reality independent of human intervention, and those about its undeniably constructed character. The environment, then, seems to be a concept that shows how non-epistemic and epistemic notions of reality (i.e. respectively seeing reality as independent from and dependent on us) can be understood cohesively., Je realita ,,Ready-Made World'' nebo subjekt vytvořený jednotlivci a sociální činností? Pojem životního prostředí se zdá být hranicí, která jasně ukazuje, jak můžeme současně dodržovat naše zdánlivě protichůdné intuice - to znamená ty, které se týkají vnějších a autonomních rysů reality nezávislé na lidském zásahu, a těch, které mají nesporně postavený charakter. Zdá se tedy, že životní prostředí je pojmem, který ukazuje, jak lze soudržně chápat neepistemické a epistemické představy o realitě (tj. Vidět realitu jako nezávislou na nás a závislou na nás)., and Salvatore Italia
This article critically examines the arguments against mechanistic neo-Darwinism offered by Thomas Nagel in his recent book Mind and Cosmos. The author argues, in particular, that Nagel’s recognition of teleology in the evolutionary process should make him less sceptical towards a panpsychist understanding of nature., James Hill., and Obsahuje poznámky a bibliografii
Intraspecific variation in genome size makes it possible to study ongoing processes of genome size evolution. Although there are over 200 papers on intraspecific variation in genome size, there is still limited understanding of this phenomenon, especially as many of these papers are based on weak methodology and therefore report biased or false evidence of the extent of intraspecific variation. In this paper the recent progress in understanding the spatio-temporal dynamics of intraspecific variation in genome size caused by the gradual accumulation of mutations is reviewed. The results of the case studies on Microseris douglasii, Zea mays, Silene latifolia, Hordeum spontaneum and Lolium hybrids, and in particular that on Festuca pallens, are discussed. The variation in genome size that occurs within species is caused mainly by differences in the content of repetitive DNA, in particular it is a consequence of the dynamics of transposable elements. Variation may be induced and maintained polytopically.We assume that it is probably more frequent in groups of young radiating species. Even in the initial stages, the variation in genome size generated within a population seems to be restricted by selection, which is also important in stabilizing genome size within species. The long-term persistence of the variation within a population and its further accumulation may be enhanced by gametes with different genome sizes, produced by the segregation of unequally sized homeologous chromosomes. Over large geographical scales and across contrasting environmental gradients, the distribution of genome sizes within species may be influenced by the nucleotype effect, with smaller genomes being more successful at higher latitudes and altitudes and under stressful conditions. However, the small differences in genome size within species seem generally to be of minor importance relative to other components of plant fitness that may be selectively favourable under particular environmental or habitat conditions. The processes generating variation in genome size may be associated with phenotypic variation. While the shift in the genome size of a population through selection enables adaptive evolution of genome size in a newly arising species, the spatio-temporal variation in genome size within an ancestral species allows for a rapid multiple genome size divergence of related species through random drift in genome size (founder effect, bottleneck effect) during range fragmentation, hybridization and/or polyploidization.