Spatially continuous patterns of genetic differentiation, which are common in nature, are often poorly described by existing population genetic theory or methods that assume either panmixia or discrete, clearly definable populations. There is therefore a need for statistical approaches in population genetics that can accommodate continuous geographic structure, and that ideally use georeferenced individuals as the unit of analysis, rather than populations or subpopulations. In addition, researchers are often interested in describing the diversity of a population distributed continuously in space; this diversity is intimately linked to both the dispersal potential and the population density of the organism.
View Article and Find Full Text PDFFisher's fundamental theorem of natural selection has haunted theoretical population genetic literature since it was proposed in 1930, leading to numerous interpretations. Most of the confusion stemmed from Fisher's own obscure presentation. By the 1970s, a clearer view of Fisher's theorem had been achieved and it was found that, regardless of its utility or significance, it represents a general theorem of evolutionary biology.
View Article and Find Full Text PDFSpatially continuous patterns of genetic differentiation, which are common in nature, are often poorly described by existing population genetic theory or methods that assume panmixia or discrete, clearly definable populations. There is therefore a need for statistical approaches in population genetics that can accommodate continuous geographic structure, and that ideally use georeferenced individuals as the unit of analysis, rather than populations or subpopulations. In addition, researchers are often interested describing the diversity of a population distributed continuously in space, and this diversity is intimately linked to the dispersal potential of the organism.
View Article and Find Full Text PDFSpecies range contractions both contribute to, and result from, biological annihilation, yet do not receive the same attention as extinctions. Range contractions can lead to marked impacts on populations but are usually characterized only by reduction in extent of range. For effective conservation, it is critical to recognize that not all range contractions are the same.
View Article and Find Full Text PDFMol Phylogenet Evol
August 2022
The tendency to discretize biology permeates taxonomy and systematics, leading to models that simplify the often continuous nature of populations. Even when the assumption of panmixia is relaxed, most models still assume some degree of discrete structure. The multispecies coalescent has emerged as a powerful model in phylogenetics, but in its common implementation is entirely space-independent - what we call the "missing z-axis".
View Article and Find Full Text PDFEcosystem engineers alter, and can be influenced in turn by, the ecosystems they live in. Woodpeckers choose foraging and nesting sites based, in part, on food availability. Once abandoned, these cavities, particularly within areas of high forage, may be crucial to secondary cavity-nesting birds otherwise limited by cavities formed through decay.
View Article and Find Full Text PDFThe Modern Synthesis (or "Neo-Darwinism"), which arose out of the reconciliation of Darwin's theory of natural selection and Mendel's research on genetics, remains the foundation of evolutionary theory. However, since its inception, it has been a lightning rod for criticism, which has ranged from minor quibbles to complete dismissal. Among the most famous of the critics was Stephen Jay Gould, who, in 1980, proclaimed that the Modern Synthesis was "effectively dead.
View Article and Find Full Text PDFIsolation-by-distance is a widespread pattern in nature that describes the reduction of genetic correlation between subpopulations with increased geographic distance. In the population ancestral to modern sister species, this pattern may hypothetically inflate population divergence time estimation due to allele frequency differences in subpopulations at the ends of the ancestral population. In this study, we analyze the relationship between the time to the most recent common ancestor and the population divergence time when the ancestral population model is a linear stepping-stone.
View Article and Find Full Text PDFUndescribed species of the genus Haustorius Müller, 1775 have long been known to exist in the Gulf of Mexico. These sand-burrowing amphipods are abundant intertidal members of fine sand beaches. Two new species are here described, Haustorius galvezi sp.
View Article and Find Full Text PDF(Actiniaria: Diadumenidae) is a prolific invader of coastal environments around the world. First described from Asia, this sea anemone has only been reported once from the western Gulf of Mexico at Port Aransas, Texas. No subsequent sampling has located this species at this locality.
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