BACKGROUND In a species with a large distribution relative to its dispersal capacity, geographic variation in traits may be explained by gene flow, selection, or the combined effects of both. Studies of genetic diversity using neutral molecular markers show that patterns of isolation by distance (IBD) or barrier effect may be evident for geographic variation at the molecular level in amphibian ...

Interspecific variations in avian visual systems have been suggested to influence antipredator strategies, yet little empirical evidence exists on how morphological and ecological factors associated with visual properties can constraint predator detection. We investigated antipredator responses (predator detection probabilities and vigilance behavior) in 2 species with different visual properti...

Why organisms diversify into discrete species instead of showing a continuum of genotypic and phenotypic forms is an important yet rarely studied question in speciation biology. Does species discreteness come from adaptation to fill discrete niches or from interspecific gaps generated by reproductive isolation? We investigate the importance of reproductive isolation by comparing genetic discret...

In intercropping distance research, traditional field experiments are time-consuming and tedious, and cannot be applied to quantitative interspecific distance quickly. Therefore it has become a big concern for researchers in this field to further reduce manual operation, and more automatically and quickly get the optimal planting distance. In this paper, an optimization algorithm was applied to...

Long-distance migratory birds have relatively smaller brains than short-distance migrants or residents. Here, we test whether reduction in brain size with migration distance can be generalized across the different brain regions suggested to play key roles in orientation during migration. Based on 152 bird species, belonging to 61 avian families from six continents, we show that the sizes of bot...

in 1909, several years before the famous `organizer’ experiments of spemann and mangold, ethel browne demonstrated induction of a secondary axis in hydra by grafting a hypostome. based on this and subsequent work, in the late sixties, lewis wolpert proposed the theory of morphogen gradients and positional information. we have studied secondary axis induction by hypostome and foot tissue using t...

The species delimitation in fungi is currently in flux. A growing body of evidence shows that the morphology-based species circumscription underestimates the number of existing species. The large and ever growing number of DNA sequence data of fungi makes it possible to use these to identify potential cases of hidden species, which then need to be studied with extensive taxon samplings. We used...

East Antarctic octopods were identified by sequencing mtCOI and using four analytical approaches: Neighbor-joining by Kimura-2-Parameter-based distances, character-based, BLAST, and Bayesian Inference of Phylogeny. Although the distance-based analytical approaches identified a high proportion of the sequences (99.5% to genus and 88.1% to species level), these results are undermined by the absen...

A new species, Alopecosa koponeni sp. n., is described from the Arctic part of Manitoba. Individuals of A. koponeni most resemble those of A. pictilis (Emerton, 1885), but are smaller than the latter and differ in the epiginum and in colour pattern in both sexes. DNA barcode results show an interspecific distance of 0.93 between A. koponeni sp. n. and A. pictilis, a shallow genetic divergence t...

A key goal of invasion biology is to identify the factors that favor species invasions. One potential indicator of invasiveness is the phylogenetic distance between a nonnative species and species in the recipient community. However, predicting invasiveness using phylogenetic information relies on an untested assumption: that both biotic resistance and facilitation weaken with increasing phylog...