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Long-term datasets are becoming increasingly important for assessing population- and species-level responses to a changing environment. Programs that record morphological measurements of horns, antlers, and pronghorns were established in the early- to mid-20th century to collect biological information about animals that possess large horns, antlers, or pronghorns, which could be used to assess the effectiveness of conservation efforts for large mammals in North America. The general relevance of record books has been questioned because of the minimum size requirements for inclusion in a record book, which may mask trends when changes in the population occur. We compared trends in size of antlers, horns, and pronghorns through time using records from three records programs with different minimum size requirements to evaluate the influence of entry requirements on temporal trends. We also investigated whether horn, antler, or pronghorn size affected the probability of specimens being submitted to a records program. Only two of 17 categories exhibited less-pronounced trends in the record book with the highest size requirements for entry, and in two categories trends were more pronounced. Although societal interest in submitting eligible specimens increased slightly over time in one of six categories, the probability of voluntary entry was largely random and not affected by year of harvest or size of specimen. In contrast to previous criticisms, trends in record books should not be expected to represent the size of all males within a population. Instead, our evaluation indicates that the records programs we examined can provide a useful resource for assessing long-term changes in phenotypic characteristics of ungulates, but importantly, they represent the respective range of sizes within which each program collects data. [ABSTRACT FROM AUTHOR]

Aim: Phenology, the temporal response of a population to its climate, is a crucial behavioural trait shared across life on earth. How species adapt their phenologies to climate change is poorly understood but critical in understanding how species will respond to future change. We use a group of flies (Rhaphiomidas) endemic to the North American deserts to understand how species adapt to changing climatic conditions. Here, we explore a novel approach for taxa with constrained phenologies aimed to accurately model their environmental niche and relate this to phenological and morphological adaptations in a phylogenetic context. Taxon: Insecta, Diptera, Mydidae, Rhaphiomidas. Location: North America, Mojave, Sonoran and Chihuahuan Deserts. Methods: We gathered geographical and phenological occurrence data for the entire genus Rhaphiomidas, and, estimated a time calibrated phylogeny. We compared Daymet derived temperature values for a species adult occurrence period (phenology) with those derived from WorldClim data that is partitioned by month or quarter to examine what effect using more precise data has on capturing a species' environmental niche. We then examined to what extent phylogenetic signal in phenological traits, climate tolerance and morphology can inform us about how species adapt to different environmental regimes. Results: We found that the Bioclim temperature data, which are averages across monthly intervals, poorly represent the climate windows to which adult flies are actually adapted. Using temporally relevant climate data, we show that many species use a combination of morphological and phenological changes to adapt to different climate regimes. There are also instances where species changed only phenology to track a climate type or only morphology to adapt to different environments. Main Conclusions: Without using a fine‐scale phenological data approach, identifying environmental adaptations could be misleading because the data do not represent the conditions the animals are actually experiencing. We find that fine‐scale phenological niche models are needed when assessing taxa that have a discrete phenological window that is key to their survival, accurately linking environment to morphology and phenology. Using this approach, we show that Rhaphiomidas use a combination of niche tracking and adaptation to persist in new niches. Modelling the effect of phenology on such species' niches will be critical for better predictions of how these species might respond to future climate change. [ABSTRACT FROM AUTHOR]

Abstract: The metacommunity concept underlies many explanations for spatial variation in species diversity. However, to date, there are been only vague definitions of how to empirically construct descriptions of these important phenomena. We develop methods for constructing metacommunity descriptions based on the concept that each local community has a distinct metacommunity that contributes immigrants to that community. We call the community for which a metacommunity is constructed the focal community. We discuss three criteria for constructing metacommunity descriptions based on geographic distances, environmental distances, and phylogenetic distances. We develop objective measures for constructing subsets of local communities into the “best” metacommunity description for a given focal community using each of the three criteria. We illustrate these methods using data on abundance estimates on 1393 local surveys of North America breeding birds. For each survey route measures of environmental conditions were obtained and used to calculate environmental distances among the survey routes. In addition, using a phylogenetic hypothesis describing relationships among bird families, we obtained measures of phylogenetic distances among survey routes. Metacommunities constructed using geographic distances were closely correlated with those constructed using environmental distances, however, metacommunities constructed using family level phylogenetic distances were less representative of local communities than those constructed using the other distance measures. Our results imply that it is possible to obtain empirical descriptions of metacommunities related to communities of interest that can be used to develop rigorous empirical tests of mechanisms thought to be responsible for patterns in species diversity in space and time. [Copyright &y& Elsevier]