Somatic cell nuclei can be dedifferentiated in ooplasm from another species, and interspecies cloned embryos can be implanted into the uteri of surrogates. However, no full pregnancies have been achieved through interspecific mammalian cloning. Rat blastocysts transferred into mouse uteri provide a unique model for studying the causes of interspecific pregnancy failure. In this study, intraspec...

PREMISE OF THE STUDY Darwin first proposed that species with larger ecological breadth have greater phenotypic variation. We tested this hypothesis by comparing intraspecific variation in specific leaf area (SLA) to species' local elevational range and by assessing how external (abiotic) filters may influence observed differences in ecological breadth among species. Understanding the patterns o...

Intraspecific phenotypic variation in ecologically important traits is widespread and important for evolutionary processes, but its effects on community and ecosystem processes are poorly understood. We use life history differences among populations of alewives, Alosa pseudoharengus, to test the effects of intraspecific phenotypic variation in a predator on pelagic zooplankton community structu...

-T~~ intensity of intraspecific competition under different levels of light and nitrogen supply was assessed for the temperate zone herb, Chenopodium album. Plants were grown at two densities (one or six plants/pot) in a modified factorial design with three levels each of light and nitrogen availability. This yielded five light/nitrogen treatments which comprised two gradients, one extending fr...

Reconstructions of the human-African great ape phylogeny by using mitochondrial DNA (mtDNA) have been subject to considerable debate. One confounding factor may be the lack of data on intraspecific variation. To test this hypothesis, we examined the effect of intraspecific mtDNA diversity on the phylogenetic reconstruction of another Plio-Pleistocene radiation of higher primates, the fascicular...

Leaf Economics Spectrum (LES) trait variation underpins multiple agroecological processes and many prominent crop yield models. While there are numerous independent studies assessing trait variation in crops, to date there have been no comprehensive assessments of intraspecific trait variation (ITV) in LES traits for wheat and maize: the world's most widespread crops. Using trait databases and ...

Intraspecific gene evolution cannot always be represented by a bifurcating tree. Rather, population genealogies are often multifurcated, descendant genes coexist with persistent ancestors and recombination events produce reticulate relationships. Whereas traditional phylogenetic methods assume bifurcating trees, several networking approaches have recently been developed to estimate intraspecifi...

In macroevolutionary studies, different approaches are commonly used to measure phylogenetic signal--the tendency of related taxa to resemble one another--including the K statistic and the Mantel test. The latter was recently criticized for lacking statistical power. Using new simulations, we show that the power of the Mantel test depends on the metrics used to define trait distances and phylog...

Metacommunity ecology emphasizes the role of dispersal in linking local processes across space. Competition is one such local process that can be affected by dispersal. Dispersal can influence intraspecific trait variation, thereby affecting the strength of intraspecific competition and, consequently, the relative importance of intraversus interspecific interactions. Prior research has shown th...