DNA methylation predicts age and provides insight into exceptional longevity of batsExceptionally long-lived species, including many bats, rarely show overt signs of aging, making it difficult to determine why species differ in lifespan. Here, we use DNA methylation (DNAm) profiles from 712 known-age bats, representing 26 species, to identify epigenetic changes associated with age and longevity. We demonstrate that DNAm accurately predicts chronological age. Across species, longevity is negatively associated with the rate of DNAm change at age-associated sites. Furthermore, analysis of several bat genomes reveals that hypermethylated age- and longevity-associated sites are disproportionately located in promoter regions of key transcription factors (TF) and enriched for histone and chromatin features associated with transcriptional regulation. Predicted TF binding site motifs and enrichment analyses indicate that age-related methylation change is influenced by developmental processes, while longevity-related DNAm change is associated with innate immunity or tumorigenesis genes, suggesting that bat longevity results from augmented immune response and cancer suppression.
Resource Ephemerality Drives Social Foraging in BatsBiotic predictors with phenological information improve range estimates for migrating monarch butterflies in MexicoAlthough long‐standing theory suggests that biotic variables are only relevant at local scales for explaining the patterns of species' distributions, recent studies have demonstrated improvements to species distribution models (SDMs) by incorporating predictor variables informed by biotic interactions. However, some key methodological questions remain, such as which kinds of interactions are permitted to include in these models, how to incorporate the effects of multiple interacting species, and how to account for interactions that may have a temporal dependence. We addressed these questions in an effort to model the distribution of the monarch butterfly Danaus plexippus during its fall migration (September–November) through Mexico, a region with new monitoring data and uncertain range limits even for this well‐studied insect. We estimated species richness of selected nectar plants ( Asclepias spp.) and roosting trees (various highland species) for use as biotic variables in our models. To account for flowering phenology, we additionally estimated nectar plant richness of flowering species per month. We evaluated three types of models: climatic variables only (abiotic), plant richness estimates only (biotic) and combined (abiotic and biotic). We selected models with AICc and additionally determined if they performed better than random on spatially withheld data. We found that the combined models accounting for phenology performed best for all three months, and better than random for discriminatory ability but not omission rate. These combined models also produced the most ecologically realistic spatial patterns, but the modeled response for nectar plant richness matched ecological predictions for November only. These results represent the first model‐based monarch distributional estimates for the Mexican migration route and should provide foundations for future conservation work. More generally, the study demonstrates the potential benefits of using SDM‐derived richness estimates and phenological information for biotic factors affecting species distributions.
Molecular Systematics of the Fishing Bat Myotis (Pizonyx) vivesiPhylogenetic reconstructions based on molecular data have shown recurrent morphological convergence during evolution of the species-rich genus Myotis. Species or groups of species with similar feeding strategies have evolved independently several times to produce remarkable similarities in external morphology. In this context, we investigated the contentious phylogenetic position of 1 of the 2 piscivorous bat species, Myotis vivesi, which was not included in previous molecular studies. This bat, endemic to the coasts and islands of the Gulf of California, Mexico, was long classified in its own genus, Pizonyx, because of its distinctive morphology. To reconstruct its phylogenetic origins relative to other Myotis, we sequenced the mitochondrial cytochrome-b gene of 2 M. vivesi and related vespertilionids. These outgroups included Pipistrellus subflavus, a member of the subgenus Perimyotis, sometimes classified within the genus Myotis. Unexpectedly, all reconstructions placed M. vivesi within a strongly supported clade including all other typical neotropical and Nearctic Myotis. This molecular phylogeny supports an endemic radiation of New World Myotis. Other Myotis species with similar adaptations to gaffing prey from the water surface present no close phylogenetic relationships with M. vivesi, indicating that such adaptations are convergences. On the other hand, P. subflavus is genetically as distant from the genus Myotis as from other Pipistrellus species, suggesting that generic rank to Perimyotis is warranted
Biodiversidad de Chordata (Mammalia) en MéxicoLos mamíferos son uno de los grupos más conspicuos de las comunidades terrestres de vertebrados ymuestran una serie de características internas y externas que los han llevado a ser exitosos en casi todos los ecosistemasdel mundo. El objetivo de esta revisión es actualizar el estado de conocimiento de los mamíferos de México. EnMéxico los mamíferos forman un grupo altamente diverso, ubicando al país en el tercer lugar mundial con 564especies silvestres, alcanzando aproximadamente el 10% de la diversidad total. La descripción de las especies no hasido homogénea a lo largo del tiempo y tuvo un mayor auge desde mediados de 1700 hasta 1950. La distribución delos mamíferos incluye todo el territorio nacional; el 77% son especies menores a 5 kg y pertenecen, principalmente,a los órdenes Rodentia, Chiroptera y Soricomorpha. Las tendencias poblacionales están poco documentadas en lamayoría de los órdenes pero, en general, los mamíferos han visto disminuidas sus poblaciones como resultado de lasactividades antrópicas. La información analizada sugiere que a pesar de que el grupo de los mamíferos en México esuno de los más estudiados, continúa ofreciendo interesantes retos teóricos y de manejo.