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Under an adaptive hypothesis, the reciprocal influence between mutualistic plants and frugivores is expected to result in suites of matching frugivore and plant traits that structure fruit consumption. Recent work has suggested fruit traits can represent adaptations to broad groups of functionally similar frugivores, but the role of frugivore traits and within-species variation in structuring fruit consumption is less understood. To address these knowledge gaps, we assess the presence of reciprocal trait matching for the mutualistic ecological network comprising of 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 frugivore adaptation to their dietary composition and suggesting niche partitioning among Carollia bats, we find differential consumption of a suite of Piper species influenced by bat traits such as body size; however, the Piper morphological traits considered 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. # Data from: Frugivore traits predict plant-frugivore interactions using generalized joint attribute modeling [https://doi.org/10.5061/dryad.2v6wwpzwg](https://doi.org/10.5061/dryad.2v6wwpzwg) Bayesian models relating: 1\. head.R: relates *Carollia* traits to bite force (performance) via hierarchical ML models 2\. carollia3_0.R: relates *Carollia* traits to bite force (performance) via hierarchical Bayesian models 3\. gjam generated model of consumption relationship to traits for *Carollia* bats 4\. gjam processed model outputs 5\. piper.R: relates *Piper* traits and GJAM coefficients obtained from 3 and 4 ## Description of the data and file structure All cells marked as NA lacked data and correspond to missing data. ## Code/Software 1\. head.R: relates *Carollia* traits to bite force (performance) via hierarchical ML models. Requires data file bat_l_biteBody.csv and R library lme4. Prints results to .txt file. 2\. carollia3_0.R: relates *Carollia* traits to bite force (performance) via hierarchical Bayesian models. Requires data file bat_l_biteBody.csv, R library R2Jags, and 3 Jags files. The three Jags files are: * carollia_bf_size.txt * carollia_bf_mass.txt * carollia_bf_head.txt carollia3_0.R prints out the results of hierarchical Bayesian regressions in txt and saves an Rdata file. 3\. niche_Carollia.R: generates gjam model of consumption relationship t traits for *Carollia* bats Requires data files: * carollia_niche_xdata.csv: x or explanatory variables, bat traits * carollia_niche_ydata_trim.csv: y or response variables, bat consumption of *Piper* fruit from different species * carollia_type.csv: individual bat assignment to one of 3 species * and R libraries gjam, reshape2 and plyr plus function * bayesReg.R (which codes a function to run a Tobit and Bayesian regression from the NEON example here: [https://rstudio-pubs-static.s3.amazonaws.com/710083_480b1b43b4f0470691e95302483fdc08.html](https://rstudio-pubs-static.s3.amazonaws.com/710083_480b1b43b4f0470691e95302483fdc08.html)). This script generates the bayesian gjam model and saves an Rdata file. 4\. plot_Carollia_v2.r processes gjam model outputs. Requires data files: * models_Carollia.Rdata * and R libraries gjam, reshape2, plyr, ggplot2, MCMCvis and wesanderson This script generates the standardized summary and prints out a file called piper_medians.csv 5\. piper.R relates *Piper* traits and gjam coefficients obtained from steps 3 and 4.. Requires data files: * piper.nex: phylogeny of *Piper* plants * piper_k_traits.csv: correspondence between *Piper* traits and *Piper* species * output.csv: this is processed from piper_medians.csv to separate relate Piper species to bat trait values resulting from gjam * Requires R libraries MCMCglmm and geiger This script prints out the results of phylogenetic Bayesian regressions of gjam outputs as a function of *Piper* traits in txt and saves a Rdata file. 

Abstract This special issue of The Anatomical Record is inspired by and dedicated to Professor Kunwar P. Bhatnagar, whose lifelong interests in biology, and long career studying bats, inspired many and advanced our knowledge of the world's only flying mammals. The 15 articles included here represent a broad range of investigators, treading topics familiar to Prof. Bhatnagar, who was interested in seemingly every aspect of bat biology. Key topics include broad themes of bat development, sensory systems, and specializations related to flight and diet. These articles paint a complex picture of the fascinating adaptations of bats, such as rapid fore limb development, ear morphologies relating to echolocation, and other enhanced senses that allow bats to exploit niches in virtually every part of the world. In this introduction, we integrate and contextualize these articles within the broader story of bat ecomorphology, providing an overview of each of the key themes noted above. This special issue will serve as a springboard for future studies both in bat biology and in the broader world of mammalian comparative anatomy and ecomorphology. 

Adaptive radiations are bursts in biodiversity that generate new evolutionary lineages and phenotypes. However, because they typically occur over millions of years, it is unclear how their macroevolutionary dynamics vary through time and among groups of organisms. Phyllostomid bats radiated extensively for diverse diets-from insects to vertebrates, fruit, nectar, and blood-and we use their molars as a model system to examine the dynamics of adaptive radiations. Three-dimensional shape analyses of lower molars of Noctilionoidea (Phyllostomidae and close relatives) indicate that different diet groups exhibit distinct morphotypes. Comparative analyses further reveal that phyllostomids are a striking example of a hierarchical radiation; phyllostomids' initial, higher-level diversification involved an "early burst" in molar morphological disparity as lineages invaded new diet-affiliated adaptive zones, followed by subsequent lower-level diversifications within adaptive zones involving less dramatic morphological changes. We posit that strong selective pressures related to initial shifts to derived diets may have freed molars from morpho-functional constraints associated with the ancestral molar morphotype. Then, lineages with derived diets (frugivores and nectarivores) diversified within broad adaptive zones, likely reflecting finer-scale niche partitioning. Importantly, the observed early burst pattern is only evident when examining molar traits that are strongly linked to diet, highlighting the value of ecomorphological traits in comparative studies. Our results support the hypothesis that adaptive radiations are commonly hierarchical and involve different tempos and modes at different phylogenetic levels, with early bursts being more common at higher levels. 

Nasal turbinals, scrolled thin bones of the nasal cavity, increase surface area for conditioning inspired air or for olfaction in mammals. To assess function in Eptesicus fuscus (Big Brown Bat), we quantify surface area of respiratory and olfactory turbinals from birth to adult size, using data from microCT scans before and after iodine staining. Surface area of each turbinal is significantly correlated with postnatal age and cranial length. The surface area of the maxilloturbinal and first ethmoturbinal (ET I) grows faster, relative to skull size, than surface area of caudal ethmoturbinals or the frontoturbinal. Histological examination of selected specimens reveals ET I grows disproportionately more presumptive respiratory mucosa than olfactory mucosa, supporting the hypothesis that ET I has a dual function. Lastly, we find that distribution of olfactory mucosa in the caudal nasal cavity diminishes with age. Our findings suggest a reduction in olfactory function in E. fuscus, perhaps due to a diminished role in food acquisition by this aerial insectivore. 

Body size is often hypothesized to facilitate or constrain morphological diversity in the cranial, appendicular, and axial skeletons. However, how overall body shape scales with body size ( i.e. , body shape allometry) and whether these scaling patterns differ between ecological groups remains poorly investigated. Here, we test whether and how the relationships between body shape, body size, and limb lengths differ among species with different locomotor specializations, and describe the underlying morphological components that contribute to body shape evolution among squirrel (Sciuridae) ecotypes. We quantified the body size and shape of 87 squirrel species from osteological specimens held at museum collections. Using phylogenetic comparative methods, we first found that body shape and its underlying morphological components scale allometrically with body size, but these allometric patterns differ among squirrel ecotypes: chipmunks and gliding squirrels exhibited more elongate bodies with increasing body sizes whereas ground squirrels exhibited more robust bodies with increasing body size. Second, we found that only ground squirrels exhibit a relationship between forelimb length and body shape, where more elongate species exhibit relatively shorter forelimbs. Third, we found that the relative length of the ribs and elongation or shortening of the thoracic region contributes the most to body shape evolution across squirrels. Overall, our work contributes to the growing understanding of mammalian body shape evolution and how it is influenced by body size and locomotor ecology, in this case from robust subterranean to gracile gliding squirrels. 

Abstract Tooth classes are an innovation that has contributed to the evolutionary success of mammals. However, our understanding of the mechanisms by which tooth classes diversified remain limited. We use the evolutionary radiation of noctilionoid bats to show how the tooth developmental program evolved during the adaptation to new diet types. Combining morphological, developmental and mathematical modeling approaches, we demonstrate that tooth classes develop through independent developmental cascades that deviate from classical models. We show that the diversification of tooth number and size is driven by jaw growth rate modulation, explaining the rapid gain/loss of teeth in this clade. Finally, we mathematically model the successive appearance of tooth buds, supporting the hypothesis that growth acts as a key driver of the evolution of tooth number and size. Our work reveal how growth, by tinkering with reaction/diffusion processes, drives the diversification of tooth classes and other repeated structure during adaptive radiations. 

Abstract Natural history collections are repositories of biodiversity specimens that provide critical infrastructure for studies of mammals. Over the past 3 decades, digitization of collections has opened up the temporal and spatial properties of specimens, stimulating new data sharing, use, and training across the biodiversity sciences. These digital records are the cornerstones of an “extended specimen network,” in which the diverse data derived from specimens become digital, linked, and openly accessible for science and policy. However, still missing from most digital occurrences of mammals are their morphological, reproductive, and life-history traits. Unlocking this information will advance mammalogy, establish richer faunal baselines in an era of rapid environmental change, and contextualize other types of specimen-derived information toward new knowledge and discovery. Here, we present the Ranges Digitization Network (Ranges), a community effort to digitize specimen-level traits from all terrestrial mammals of western North America, append them to digital records, publish them openly in community repositories, and make them interoperable with complimentary data streams. Ranges is a consortium of 23 institutions with an initial focus on non-marine mammal species (both native and introduced) occurring in western Canada, the western United States, and Mexico. The project will establish trait data standards and informatics workflows that can be extended to other regions, taxa, and traits. Reconnecting mammalogists, museum professionals, and researchers for a new era of collections digitization will catalyze advances in mammalogy and create a community-curated trait resource for training and engagement with global conservation initiatives.