We tested the hypothesis that Uniola paniculata populations are divided into eastern and western lineages, with the primary geographic break at the southern tip of Florida, as observed in codistributed animal taxa. We asked whether the geographic distribution of chloroplast DNA (cpDNA) variation in U. paniculata corresponds to 1) genetic structure in nuclear variation reported in previous studi...

One of the ongoing goals of evolutionary biology is to understand geographic variation in organism phenotypes along environmental gradients. Phenotypic differences among populations can reflect local adaptation, which results from genetic differentiation among populations, phenotypic plasticity, which results from phenotypic variation in a genotype along an environmental gradient, or, a combina...

Recent events, including the Indian Ocean tsunami, the hurricanes of the 2005 season, and the 7/7 and 9/11 terrorist attacks, have made us all acutely aware of the vulnerability of modern society. Knowing where such events have occurred and the geographic limits of their impacts is clearly important, particularly when combined with information on human populations, infrastructure, and other spa...

Morphological variation among geographic populations of the New World sand fly Lutzomyia quinquefer (Diptera, Phlebotominae) was analyzed and patterns detected that are probably associated with species emergence. This was achieved by examining the relationships of size and shape components of morphological attributes, and their correlation with geographic parameters. Quantitative and qualitativ...

High resolution mitochondrial DNA (mtDNA) restriction maps, consisting of an average of 370 sites per mtDNA map, were constructed for 119 people from 25 localities in Papua New Guinea (PNG). Comparison of these PNG restriction maps to published maps from Australian, Caucasian, Asian and African mtDNAs reveals that PNG has the lowest amount of mtDNA variation, and that PNG mtDNA lineages origina...

Small populations are more prone to extinction if the dispersal among them is not adequately maintained by ecological connections. The degree of isolation between populations could be evaluated measuring their genetic distance, which depends on the respective geographic (isolation by distance, IBD) and/or ecological (isolation by resistance, IBR) distances. The aim of this study was to assess t...

Accurate predictions regarding how climate change affects species and populations are crucial for the development of effective conservation measures. However, models forecasting the impact of climate change on natural environments do not often consider the geographic variation of an organism's life history. We examined variation in developmental plasticity to changing temperature in the pool fr...

Evolutionary changes in the seasonal timing of life-history events can alter a population's exposure to seasonally variable environmental factors. We illustrate this principle in Wyeomyia smithii by showing that: (1) geographic divergence in diapause timing reduces differences among populations in the thermal habitat experienced by nondiapause stages; and (2) the thermal habitat of the growing ...

INTRODUCTlON ,. . The foundation of most evolutionary theory rests upon inferences drawn from geographic variation or upon the verification of predictions made about it. The study of geographic variation occupies a central position in evolutionary biology. .. because geographic variation is ordinarily the smallest amount of evolution that can be detected in nature and because evolutionary theor...