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An ecological issue can best be studied by gathering original data that are specifically targeted for that issue. But ascertaining—a priori—whether a novel issue will be worth exploring can be problematic without background data. However, an issue's potential merit can sometimes be evaluated by repurposing legacy or other data that had been gathered for unrelated purposes but that are nonetheless relevant. Our present project was initially motivated by an ecological trade-off—proposed eight decades ago—involving the depth at which desert reptiles overwintered. To address those and related issues, we repurposed our five-decades-old natural history data for 18 species of Kgalagadi lizards and then explored the seasonal ecology of these lizards, emphasizing winter. Our data were not gathered for a study of seasonal ecology but nonetheless inform diverse seasonal patterns for a major community of lizards. However, repurposed data (whether recent or legacy) present challenges and ambiguities, and we suggest targeted, next-step studies of seasonal ecology that can circumvent limitations and ambiguities. [ABSTRACT FROM AUTHOR]

A method was devised to identify the variations in life history traits that are due to phylogenetic effects. First, the taxonomic level at which most of the variation is associated was evaluated by nested ANCOVAs. An intraclass correlation coefficient, which measures the differences among descendant taxa at any given level, was subsequently calculated. Finally, a network autocorrelation method was used to map the species' life history attributes onto their evolutionary relationships, thus showing variation patterns that are explainable in terms of phylogenetic interrelationships.

Presents information on a study that examined how well the thermal dependence of development time and lifetime fecundity correlate with the thermal dependence of ectotherm fitness. Methodology of the study; Results and discussion on the study.

We investigated the generality of the correlation between feeding behavior and morphology in assemblages of insectivorous passerine birds. We outlined an approach that satisfies two criteria necessary for demonstrating the concordance of ecological relationships among communities. First, we determined that ecomorphological correlations were consistently strong within assemblages under comparison by canonical-correlation analysis. Second, the similarity of the ecomorphological-distance relationships among assemblages (i.e., in analogy to the similarity of slopes in a regression analysis) was analyzed by multiple-regression analysis and analysis of covariance (ANCOVA). Our analysis was based on foraging and morphological measurements obtained from passerine birds from localities in New Hampshire, Costa Rica, and St. Kitts. Our within-assemblage analyses demonstrated a strong association between ecology and morphology for the Hubbard Brook site and for the pooled sample of Costa Rica and St. Kitts. Although the correlations were strong, the temperate and tropical localities differed in the foraging variables and morphological traits that described the relationship. These results suggest a consistent relationship between morphology and feeding behavior, but we were not able to distinguish among-locality differences. A pooled canonical analysis of all three assemblages revealed two strong, significant correlations to which species in all three localities contributed, suggesting that species in the three localities share a common ecomorphological pattern. Because canonical-correlation analysis lacks the power to distinguish the contribution of each assemblage to the overall correlation, we used an ANCOVA to test for heterogeneity in the ecomorphological association. We employed a stepwise multiple-regression procedure to reduce the number of morphological measurements used in the ANCOVA. Significant models were found only for the foraging variables summarized by the first two reciprocal-averaging axes. Two ANCOVA's were subsequently performed, revealing significant unadjusted locality effects. In both analyses, however, the locality effects vanished when adjusted for differences in the morphological covariates. With one exception, both models lacked a significant interaction term between the morphological covariates and locality. Overall, the results indicate a homogeneity in ecomorphological correlations among passerine assemblages. [ABSTRACT FROM AUTHOR]