bats

Frugivore traits predict plant-frugivore interactions using generalized joint attribute modeling
Under an adaptive hypothesis, the reciprocal influence between mutualistic plants and frugivores is expected to result in dispersal syndromes comprising both frugivore and plant traits that structure fruit consumption. How frugivore traits and within-species variation contribute to structuring dispersal syndromes is, however, often ignored. To address both gaps, we analyze traits for the mutualistic ecological network comprising Carollia bats that feed on and disperse Piper seeds. We used generalized joint attribute modeling (GJAM), a Bayesian modeling approach that simultaneously accounts for multiple sources of variance across trait types. In support of the adaptive hypothesis and indicating niche partitioning among Carollia bats, we find differential consumption of a suite of Piper species influenced by bat traits such as body size; however, Piper morphological traits had no effect on bat consumption. Slow evolutionary rates, dispersal by other vertebrates, and unexamined fruit traits, such as Piper chemical bouquets, may explain the lack of association between bat Piper consumption and fruit morphological traits. We have identified a potential asymmetric influence of frugivore traits on plant-frugivore interactions, providing a template for future trait analyses of plant-animal networks. As intraspecific trait variation is rarely included in studies on trait matching, this paper contributes to closing that important knowledge gap.
Newly assembled pocket gopher genomes can facilitate conservation management of biodiversity
Texas exhibits one of the richest levels of pocket gopher diversity in the United States. Three genera (Cratogeomys, Geomys, and Thomomys) and 11 species are found in Texas. It is not surprising given the diversity of the Texas landscape (ecoregions, life zones, substrates, and vegetation) that these species are further subdivided into 29 subspecies in Texas alone. Pocket gopher distributions are determined by availability of suitable soil types and therefore often occur in small, isolated populations. For some taxa, limited distribution and ultimately small deme sizes result in populations that may require attention from a regulatory and management perspective. For many Texas pocket gopher subspecies, insufficient information exists to make sound recommendations relative to conservation status and needs despite decades of research collecting and evaluating data based on morphometrics, distributions and habitat preferences, karyotypes, allozymes, and mitochondrial DNA. As such, there is precedent for elevating pocket gopher subspecies to species after evaluation of available data, as well as subsuming subspecies into a broader taxonomic group. We used genomic techniques to identify genetically defined operational taxonomic units (OTUs) of pocket gophers to improve knowledge and understanding of pocket gopher distributions within the state. Using tens of thousands of single nucleotide polymorphisms, we determined the number of OTUs in each genus to be 5 for Thomomys bottae subspecies, 8 for Geomys species, and 5 for Cratogeomys castanops subspecies in Texas. In general, these data agree with current taxonomic hypotheses regarding Geomys and C. castanops; however, many T. bottae groups present similar genetic patterns that do not merit subspecies status based on these data, suggesting a more conservative classification of T. bottae in Texas and southeastern New Mexico that could facilitate conservation efforts, should they be necessary.
Bat genomes illuminate adaptations to viral tolerance and disease resistance
Zoonoses are infectious diseases transmitted from animals to humans. Compared to other mammalian orders, bats are suggested to harbor more zoonotic viruses(Olival et al. 2017). Infections in bats are largely asymptomatic(Schlottau et al. 2020; Guito et al. 2021), suggesting limited tissue-damaging inflammation and immunopathology. To investigate the genomic basis of disease resistance, the Bat1K project generated reference-quality genomes of ten bat species, including potential viral reservoirs. A systematic analysis covering 115 mammalian genomes revealed that signatures of selection in immune genes are more prevalent in bats compared with other mammalian orders. We found an excess of immune gene adaptations in the ancestral chiropteran branch and in many descending bat lineages, highlighting viral entry and detection factors, and regulators of antiviral and inflammatory responses. ISG15, an antiviral gene contributing to hyperinflammation during COVID-19(Perng and Lenschow 2018; Munnur et al. 2021), exhibits key residue changes in rhinolophid and hipposiderid bats. Cellular infection experiments show species-specific antiviral differences and an essential role offor protein conjugation in antiviral function of bat ISG15, separate from its role in secretion and inflammation in humans. Furthermore, in contrast to human ISG15, ISG15 of most rhinolophid and hipposiderid bats has strong anti-SARS-CoV-2 activity. Our work reveals molecular mechanisms contributing to viral tolerance and disease resistance in bats.