Exon capture museomics deciphers the nine-banded armadillo species complex and identifies a new species endemic to the Guiana Shield.

The nine-banded armadillo (Dasypus novemcinctus) is the most widespread xenarthran species across the Americas. Recent studies have suggested it is composed of four morphologically and genetically distinct lineages of uncertain taxonomic status. To address this issue, we used a museomic approach to sequence 80 complete mitogenomes and capture 997 nuclear loci for 71 Dasypus individuals sampled across the entire distribution. We carefully cleaned up potential genotyping errors and cross contaminations that could blur species boundaries by mimicking gene flow. Our results unambiguously support four distinct lineages within the D. novemcinctus complex. We found cases of mito-nuclear phylogenetic discordance but only limited contemporary gene flow confined to the margins of the lineage distributions. All available evidence including the restricted gene flow, phylogenetic reconstructions based on both mitogenomes and nuclear loci, and phylogenetic delimitation methods consistently supported the four lineages within D. novemcinctus as four distinct species. Comparable genetic differentiation values to other recognized Dasypus species further reinforced their status as valid species. Considering congruent morphological results from previous studies, we provide an integrative taxonomic view to recognise four species within the D. novemcinctus complex: D. novemcinctus, D. fenestratus, D. mexicanus, and D. guianensis sp. nov., a new species endemic of the Guiana Shield that we describe here. The two available individuals of D. mazzai and D. sabanicola were consistently nested within D. novemcinctus lineage and their status remains to be assessed. The present work offers a case study illustrating the power of museomics to reveal cryptic species diversity within a widely distributed and emblematic species of mammals.

Mammalian diversification bursts and biotic turnovers are synchronous with Cenozoic geoclimatic events in Asia.

Asia's rich species diversity has been linked to its Cenozoic geodiversity, including active mountain building and dramatic climatic changes. However, prior studies on the diversification and assembly of Asian faunas have been derived mainly from analyses at taxonomic or geographic scales too limited to offer a comprehensive view of this complex region's biotic evolution. Here, using the class Mammalia, we built historical biogeographic models drawn on phylogenies of 1,543 species occurring across Asia to investigate how and when the mammal diversity in Asian regions and mountain hotspots was assembled. We explore the roles of in situ speciation, colonization, and vicariance and geoclimatic events to explain the buildup of Asia's regional mammal diversity through time. We found that southern Asia has served as the main cradle of Asia's mammal diversity. Present-day species richness in other regions is mainly derived from colonization, but by the Miocene, in situ speciation increased in importance. The high biodiversity present in the mountain hotspots (Himalayas and Hengduan) that flank the Qinghai-Tibetan plateau is a product of high colonization instead of in situ speciation, making them important centers of lineage accumulation. Overall, Neogene was marked by great diversification and migrations across Asia and surrounding continents but Paleogene environments already hosted rich mammal assemblages. Our study revealed that synchronous diversification bursts and biotic turnovers are temporally associated with tectonic events (mountain building, continental collisions) and drastic reorganization of climate (aridification of Asian interior, intensification of Asian monsoons, sea retreat) that took place throughout the Cenozoic in Asia.

Genomic Consequences of and Demographic Response to Pervasive Hybridization Over Time in Climate-Sensitive Pikas.

Rare and geographically restricted species may be vulnerable to genetic effects from inbreeding depression in small populations or from genetic swamping through hybridization with common species, but a third possibility is that selective gene flow can restore fitness (genetic rescue). Climate-sensitive pikas (Ochotona spp.) of the Qinghai-Tibetan Plateau (QHTP) and its vicinity have been reduced to residual populations through the movement of climatic zones during the Pleistocene and recent anthropogenic disturbance, whereas the plateau pika (O. curzoniae) remains common. Population-level whole-genome sequencing (n = 142) of six closely related species in the subgenus Ochotona revealed several phases of ancient introgression, lineage replacement, and bidirectional introgression. The strength of gene flow was the greatest from the dominant O. curzoniae to ecologically distinct species in areas peripheral to the QHTP. Genetic analyses were consistent with environmental reconstructions of past population movements. Recurrent periods of introgression throughout the Pleistocene revealed an increase in genetic variation at first but subsequent loss of genetic variation in later phases. Enhanced dispersion of introgressed genomic regions apparently contributed to demographic recovery in three peripheral species that underwent range shifts following climate oscillations on the QHTP, although it failed to drive recovery of northeastern O. dauurica and geographically isolated O. sikimaria. Our findings highlight differences in timescale and environmental background to determine the consequence of hybridization and the unique role of the QHTP in conserving key evolutionary processes of sky island species.

Whole-genome sequencing reveals adaptations of hairy-footed jerboas (Dipus, Dipodidae) to diverse desert environments.

BACKGROUND: Environmental conditions vary among deserts across the world, spanning from hyper-arid to high-elevation deserts. However, prior genomic studies on desert adaptation have focused on desert and non-desert comparisons overlooking the complexity of conditions within deserts. Focusing on the adaptation mechanisms to diverse desert environments will advance our understanding of how species adapt to extreme desert environments. The hairy-footed jerboas are well adapted to diverse desert environments, inhabiting high-altitude arid regions, hyper-arid deserts, and semi-deserts, but the genetic basis of their adaptation to different deserts remains unknown. RESULTS: Here, we sequenced the whole genome of 83 hairy-footed jerboas from distinct desert zones in China to assess how they responded under contrasting conditions. Population genomics analyses reveal the existence of three species in hairy-footed jerboas distributed in China: Dipus deasyi, Dipus sagitta, and Dipus sowerbyi. Analyses of selection between high-altitude desert (elevation ≥ 3000m) and low-altitude desert (< 500m) populations identified two strongly selected genes, ATR and HIF1AN, associated with intense UV radiation and hypoxia in high-altitude environments. A number of candidate genes involved in energy and water homeostasis were detected in the comparative genomic analyses of hyper-arid desert (average annual precipitation < 70mm) and arid desert (< 200mm) populations versus semi-desert (> 360mm) populations. Hyper-arid desert animals also exhibited stronger adaptive selection in energy homeostasis, suggesting water and resource scarcity may be the main drivers of desert adaptation in hairy-footed jerboas. CONCLUSIONS: Our study challenges the view of deserts as homogeneous environments and shows that distinct genomic adaptations can be found among desert animals depending on their habitats.

Demographic History and Genomic Response to Environmental Changes in a Rapid Radiation of Wild Rats.

For organisms to survive and prosper in a harsh environment, particularly under rapid climate change, poses tremendous challenges. Recent studies have highlighted the continued loss of megafauna in terrestrial ecosystems and the subsequent surge of small mammals, such as rodents, bats, lagomorphs, and insectivores. However, the ecological partitioning of these animals will likely lead to large variation in their responses to environmental change. In the present study, we investigated the evolutionary history and genetic adaptations of white-bellied rats (Niviventer Marshall, 1976), which are widespread in the natural terrestrial ecosystems in Asia but also known as important zoonotic pathogen vectors and transmitters. The southeastern Qinghai-Tibet Plateau was inferred as the origin center of this genus, with parallel diversification in temperate and tropical niches. Demographic history analyses from mitochondrial and nuclear sequences of Niviventer demonstrated population size increases and range expansion for species in Southeast Asia, and habitat generalists elsewhere. Unexpectedly, population increases were seen in N. eha, which inhabits the highest elevation among Niviventer species. Genome scans of nuclear exons revealed that among the congeneric species, N. eha has the largest number of positively selected genes. Protein functions of these genes are mainly related to olfaction, taste, and tumor suppression. Extensive genetic modification presents a major strategy in response to global changes in these alpine species.

A multi-faceted comparative perspective on elevational beta-diversity: the patterns and their causes.

The observed patterns and underlying mechanisms of elevational beta-diversity have been explored intensively, but multi-dimensional comparative studies remain scarce. Herein, across distinct beta-diversity components, dimensions and species groups, we designed a multi-faceted comparative framework aiming to reveal the general rules in the observed patterns and underlying causes of elevational beta-diversity. We have found that: first, the turnover process dominated altitudinal patterns of species beta-diversity (ßsim > ßsne), whereas the nestedness process appeared relatively more important for elevational trait dissimilarity (ßfuncsim < ßfuncsne); second, the taxonomic turnover was relative higher than its phylogenetic and functional analogues (ßsim > ßphylosim/ßfuncsim), conversely, nestedness-resultant trait dissimilarity tended to be higher than the taxonomic and phylogenetic measures (ßfuncsne > ßsne/ßphylosne); and third, as elevational distance increased, the contradicting dynamics of environmental filtering and limiting similarity have jointly led the elevational patterns of beta-diversity, especially at taxonomic dimension. Based on these findings, we infer that the species turnover among phylogenetic relatives sharing similar functional attributes appears to be the main cause of shaping the altitudinal patterns of multi-dimensional beta-diversity. Owing to the methodological limitation in the randomization approach, currently, it remains extremely challenging to distinguish the influence of the neutral process from the offset between opposing niche-based processes. Despite the complexities and uncertainties during species assembling, with a multi-dimensional comparative perspective, this work offers us several important commonalities of elevational beta-diversity dynamics.

Ring distribution patterns-diversification or speciation? Comparative phylogeography of two small mammals in the mountains surrounding the Sichuan Basin.

Studying the genetic differentiation in a unique geographical area contributes to understanding the process of speciation. Here, we explore the spatial genetic structure and underlying formation mechanism of two congeneric small mammal species (Apodemus draco and A. chevrieri), which are mainly distributed in the mountains surrounding the lowland Sichuan Basin, southwest China. We applied a set of comparative phylogeographical analyses to determine their genetic diversification patterns, combining mitochondrial (Cytb and COI) and nuclear (microsatellite loci) markers, with dense sampling throughout the range (411 A. draco from 21 sites and 191 A. chevrieri from 22 sites). Moreover, we performed three complementary statistical methods to investigate the correlation between genotype and geographical and environmental components, and predicted the potential suitable distributional range under the present and historical climate conditions. Our results suggest that both species have experienced allopatric differentiation and admixture in historical periods, resulting in a ring-shape diversification, under the barrier effect of the Sichuan Basin. We infer that the tectonic events of the Qinghai-Tibetan Plateau and climatic oscillations during the Quaternary played an important role on the genetic divergence of the two species by providing environmental heterogeneity and geographical variation. Our study reveals a case of two sympatric small mammals following a ring-shaped diversification pattern and provides insight into the process of differentiation.

Updated and annotated checklist of recent mammals from Brazil.

An updated and annotated checklist of mammals occurring in Brazil is presented. A total of 751 native species, distributed in 249 genera, 51 families and 11 orders were recorded to the country. The Brazilian mammalian fauna shows an elevated rate of endemism (30%; 223 species). Among the species evaluated by IUCN (668 species; 90%), a total of 80 (10.6% of total mammalian fauna) are Threatened, 28 (3.9%) are considered as Near Threatened, two species (0.3%) are presumable Extinct, 96 (12.8%) are considered with Deficient Data for conservation and 462 (61.6%) are considered as Least Concern. Fifteen new species were described since the last national compilation (published in 2017), which associated to new records to the country and synonimizations resulted in an increment of 30 species. Eight non-native species were introduced to the country, including the recently established Asiatic cervids Rusa unicolor (sambar) and Axis axis (chital). Seven native species (five primates and two hystricomorph rodents) have been translocated from their areas of natural occurrence to other areas inside the country.

Research trends on bats in China: A twenty-first century review.

In this century, China has sustained unparalleled economic development, leading to exponentially growing investments in scientific research. Yet, the demand for research-funding is large and tracing the current knowledge is a key step to define priority research topics. In this same span, studies on bats in China have uncovered an overlooked diversity and revealed novelties in bats' evolutionary history and life-history aspects. All this 21st-century knowledge, however, is scattered and a large part is concealed from most of the international scientific community in Mandarin-language articles. Here, we summarize the post-millennium (2000-2017) research on bats in China and point out trends and future directions based on neglected topics, groups, and regions. In addition, we provide an up-to-date list of bat species in China. We retrieved 594 publications related to bats in China, nearly half were written in Mandarin. At least 147 bat species are present in China, which places it among the most bat-rich countries in the world. There was a significant positive trend on the number of publications, from 12.5 annual average in 2000-2005 to 46.5 in recent years, reflecting the Chinese economic-scientific development in this century. We found marked taxonomic and spatial biases. Half of the studies in this century focused on Rhinolophus, Myotis, and Hipposideros, and the southern and eastern provinces were the most studied. Systematic/taxonomy and Ecology were the predominant topics post-millennium, whereas only 10 articles have clear conservation-driven goals. Our review shows that the majority of studies were focused on the least concern, cave-dweller species, and on bat-rich provinces. Future projects should address the effects of human-modified landscapes on bat community to define proper conservation actions. We discuss some priority actions and projects that will help to enhance bat protection in China.

Distribution of tolypeutes illiger, 1811 (xenarthra: cingulata) with comments on its biogeography and conservation.

This study reviews the data available on the distribution of three-banded armadillos of the genus Tolypeutes, identifying potential geographic barriers and evaluating possible biogeographic processes that may account for the present-day distribution of the species and its conservation status. The database was derived from published records, interviews, and voucher specimens, over a timescale ranging from the fossil record to specimens collected in 2013. A total of 236 localities were recorded, with 68 attributed to Tolypeutes matacus and 168 to Tolypeutes tricinctus. The vegetation within the range of the genus is predominantly a xerophytic mosaic of grassland, savannas, open woodland, and xeric thorn forest. The marine transgressions of the Miocene and the uplifting of the Brazilian Shield may have contributed to the vicariant separation of the ancestral populations of T. matacus, to the west and south, and T. tricinctus, to the north and east. The three-banded armadillo is possibly one of the most threatened of Brazilian mammals, considering the low number of recent records and the fact that it is hunted intensively throughout its range.

Similar adaptative mechanism but divergent demographic history of four sympatric desert rodents in Eurasian inland.

Phenotypes associated with metabolism and water retention are thought to be key to the adaptation of desert species. However, knowledge on the genetic changes and selective regimes on the similar and divergent ways to desert adaptation in sympatric and phylogenetically close desert organisms remains limited. Here, we generate a chromosome level genome assembly for Northern three-toed jerboa (Dipus sagitta) and three other high-quality genome assemblies for Siberian jerboa (Orientallactaga sibirica), Midday jird (Meriones meridianus), and Desert hamster (Phodopus roborovskii). Genomic analyses unveil that desert adaptation of the four species mainly result from similar metabolic pathways, such as arachidonic acid metabolism, thermogenesis, oxidative phosphorylation, insulin related pathway, DNA repair and protein synthesis and degradation. However, the specific evolved genes in the same adaptative molecular pathway often differ in the four species. We also reveal similar niche selection but different demographic histories and sensitivity to climate changes, which may be related to the diversified genomic adaptative features. In addition, our study suggests that nocturnal rodents have evolved some specific adaptative mechanism to desert environments compared to large desert animals. Our genomic resources will provide an important foundation for further research on desert genetic adaptations.

Water Deficit at Vegetative Stage Induces Tolerance to High Temperature during Anthesis in Rice.

BACKGROUND: Crop yields have been affected by many different biotic and abiotic factors. Generally, plants experience more than one stress during their life cycle, and plants can tolerate multiple stresses and develop cross-tolerance. The expected rise in atmospheric CO2 concentration ([CO2]) can contribute to cross-tolerance. Priming is a strategy to increase yield or to maintain yield under stress conditions. Thus, our objective was to evaluate if priming the rice plants with water deficit during the vegetative stage can induce tolerance to heat stress at anthesis and to evaluate the contribution of e[CO2]. METHODS: The experiment was arranged in a completely randomized design in a factorial arrangement. Factor A consisted of the following treatments: water deficit at four-leaf stage (no-stress, and drought stress), heat at anthesis (normal temperature, high temperature), and priming with water deficit at four-leaf stage and heat stress at anthesis; and Factor B was two [CO2] treatments: a[CO2] = 400 ± 40 µmol mol-1 and e[CO2] = 700 ± 40 µmol mol-1. We assessed the effect of the treatments on plant growth, yield, biochemical, and transcriptome alterations. RESULTS: Although e[CO2] affected rice growth parameters, it did not affect the priming effect. Primed plants showed an increase in yield and number of panicles per plant. Primed plants showed upregulation of OsHSP16.9A, OsHSP70.1, and OsHSP70.6. These results showed induced cross-tolerance. CONCLUSIONS: Water deficit at the rice vegetative stage reduces the effect of heat stress at the reproductive stage. Water deficit at the vegetative stage can be used, after further testing in field conditions, to reduce the effect of heat stress during flowering in rice.

Comparative genomics of widespread and narrow-range white-bellied rats in the Niviventer niviventer species complex sheds light on invasive rodent success.

Widespread species that inhabit diverse environments possess large population sizes and exhibit a high capacity for environmental adaptation, thus enabling range expansion. In contrast, narrow-range species are confined to restricted geographical areas and are ecologically adapted to narrow environmental conditions, thus limiting their ability to expand into novel environments. However, the genomic mechanisms underlying the differentiation between closely related species with varying distribution ranges remain poorly understood. The Niviventer niviventer species complex (NNSC), consisting of highly abundant wild rats in Southeast Asia and China, offers an excellent opportunity to investigate these questions due to the presence of both widespread and narrow-range species that are phylogenetically closely related. In the present study, we combined ecological niche modeling with phylogenetic analysis, which suggested that sister species cannot be both widespread and dominant within the same geographical region. Moreover, by assessing heterozygosity, linkage disequilibrium decay, and Tajima's D analysis, we found that widespread species exhibited higher genetic diversity than narrow-range species. In addition, by exploring the "genomic islands of speciation", we identified 13 genes in highly divergent regions that were shared by the two widespread species, distinguishing them from their narrow-range counterparts. Functional annotation analysis indicated that these genes are involved in nervous system development and regulation. The adaptive evolution of these genes likely played an important role in the speciation of these widespread species.

Transcriptome analysis of pika heart tissue reveals mechanisms underlying the adaptation of a keystone species on the roof of the world.

High-altitude environments impose intense stresses on living organisms and drive striking phenotypic and genetic adaptations, such as hypoxia resistance, cold tolerance, and increases in metabolic capacity and body mass. As one of the most successful and dominant mammals on the Qinghai-Tibetan Plateau (QHTP), the plateau pika (Ochotona curzoniae) has adapted to the extreme environments of the highest altitudes of this region and exhibits tolerance to cold and hypoxia, in contrast to closely related species that inhabit the peripheral alpine bush or forests. To explore the potential genetic mechanisms underlying the adaptation of O. curzoniae to a high-altitude environment, we sequenced the heart tissue transcriptomes of adult plateau pikas (comparing specimens from sites at two different altitudes) and Gansu pikas (O. cansus). Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were used to identify differentially expressed genes (DEGs) and their primary functions. Key genes and pathways related to high-altitude adaptation were identified. In addition to the biological processes of signal transduction, energy metabolism and material transport, the identified plateau pika genes were mainly enriched in biological pathways such as the negative regulation of smooth muscle cell proliferation, the apoptosis signalling pathway, the cellular response to DNA damage stimulus, and ossification involved in bone maturation and heart development. Our results showed that the plateau pika has adapted to the extreme environments of the QHTP via protection against cardiomyopathy, tissue structure alterations and improvements in the blood circulation system and energy metabolism. These adaptations shed light on how pikas thrive on the roof of the world.

Taxonomic revision of the genus Cabassous McMurtrie, 1831 (Cingulata: Chlamyphoridae), with revalidation of Cabassous squamicaudis (Lund, 1845).

Cabassous comprises armadillos lacking a full osteoderm cover in the tail, justifying its common name naked-tailed armadillos. In the only taxonomic revision of the genus, in 1980, four living species were recognized, including a polytypic taxon with two subspecies. Recent studies have questioned this classification, but a comprehensive taxonomic review is lacking. Here, we revise the taxonomy of the genus Cabassous using complementary morphological approaches and clarify the geographical limits of naked-tailed armadillo species. Based on qualitative and quantitative analyses, we recognize five living species: C. centralis, C. chacoensis, C. squamicaudis, C. unicinctus, and C. tatouay. Most of the species can be easily differentiated using external or cranial traits, except C. centralis and C. unicinctus, which share several morphological features. The scutes pattern on the cephalic shield is an important diagnostic feature in naked-tailed armadillos and can be easily applied in field studies. Cabassous squamicaudis and C. unicinctus were previously treated as subspecies but we show they have conspicuous diagnostic traits, without mixture of characters even in closer contact. Cabassous species can be classified as open-dwellers (C. chacoensis and C. squamicaudis), forest-dwellers (C. centralis and C. unicinctus), or of more generalist habits (C. tatouay). We designate a lectotype for C. unicinctus to preserve its long-term nomenclature use.

Taxonomy of Centropomus Lacépède, 1802 (Perciformes: Centropomidae), with focus on the Atlantic species of the genus.

Centropomus Lacépède, 1802 comprises 13 species of the fishes popularly knows as snooks, distributed in both Atlantic and Pacific coasts of America. Despite several studies on the group, conflicting taxonomic classifications still exist, including overlapping diagnostic characters, rendering species diagnoses extremely difficult. Herein, we review the taxonomy of Centropomus to elucidate species identities, redefine their diagnoses and to assess interspecific relationships based on the examination of 376 specimens. The study included complementary approaches, as analyses of external morphologic characters, linear and geometric morphometrics, and molecular analyses. Forty-nine characters were used for external morphology, 17 discrete plus 32 linear measurements. Shape and size were analyzed through geometric morphometrics of 185 specimens in lateral view. Partial sequences of the gene cytochrome c oxidase I were obtained for 129 specimens representing 11 species. Based on the consistent results retrieved from the morphologic and molecular analyses, we recognized six species of Centropomus from the Atlantic coast (C. ensiferus, C. irae, C. parallelus, C. pectinatus, C. poeyi and C. undecimalis). Centropomus mexicanus is treated as a junior synonym of C. parallelus. Six species from the Pacific coast are also tentatively recognized (C. armatus, C. medius, C. nigrescens, C. robalito, C. unionensis, and C. viridis), however further studies on the Pacific species are still needed. Information on type material, diagnosis, distribution, and taxonomic comments are provided for each species. An identification key to the species of Centropomus is presented.

The role and impact of Zootaxa in mammalogy in its first 20 years.

Zootaxa came as a new and innovative publication medium for taxonomy, amidst a scenario of devaluation of this important biological science. After 20 years, it has ascertained itself as one of the main journals in animal taxonomy. However, the contribution of the journal to the taxonomy of Mammalia (mammals), one of the most studied groups of animals with a long-standing, dedicated spectrum of specialized journals (mammalogy), could have been expected as minor. All the current and former editors of the Mammalia section of Zootaxa analyzed the relative contribution of the journal to the description of new species of mammals since 2001. We also analyzed the contribution of Zootaxa by taxon, geographic origin of taxa, and geographic origin of first authors. The taxonomic methodology of authors in species description is described as well as the temporal trends in publications and publication subjects. We highlight the editors' picks and eventually, the challenges for the future. We found that Zootaxa has had a significant contribution to mammalogy, being the second journal (the first being Journal of Mammalogy) in terms of number of new species described (76; 10.6% of the new mammalian species described between 2001 and 2020). The majority of the new species were described following an integrative taxonomic approach with at least two sources of data (86%). The analysis of published taxa, their geographic origin, and the country of origin of first authors shows a wide coverage and exhaustive representation, except for the species from the Nearctic. We conclude that Zootaxa has likely responded to a repressed demand for an additional taxonomic journal in mammalogy, with as possible appeals the absence of publication fees and an established publication speed. With 246 articles published in the past 20 years, the Mammalia section of Zootaxa embraces a large spectrum of systematic subjects going beyond alpha taxonomy. The challenges for the future are to encourage publications of authors from the African continent, still poorly represented, and from the palaeontology community, as the journal has been open to palaeontology since its early days.

Elevation patterns and critical environmental drivers of the taxonomic, functional, and phylogenetic diversity of small mammals in a karst mountain area.

Understanding how biodiversity components are related under different environmental factors is a fundamental challenge for ecology studies, yet there is little knowledge of this interplay among the biotas, especially small mammals, in karst mountain areas. Here, we examine the elevation patterns of the taxonomic diversity (TD), phylogenetic diversity (PD), and functional diversity (FD) of small mammals in a karst mountain area, the Wuling Mountains, Southwest China, and compare these patterns between taxa (Rodentia and Eulipotyphla) and scales (broad- and narrow-range species). We also disentangle the impacts of the human influence index, net primary productivity (NPP), normalized difference vegetation index (NDVI), annual precipitation (AP), and annual mean temperature (AMT) on these three facets of biodiversity by using structural equation modeling. We recorded a total of 39 small mammal species, including 26 rodents and 13 species of the order Eulipotyphla. Our study shows that the facets of biodiversity are spatially incongruent. Net primary productivity has a positive effect on the three facets for most groups, while the effect of the NDVI is negative for TD and PD in most groups. AMT temperature and AP have negative effects on FD and PD, whereas TD is dependent on the species range scale. The human influence index effect on TD and PD also depends on the species range scale. These findings provide robust evidence that the ecological drivers of biodiversity differ among different biotas and different range scales, and future research should use multifacet approach to determine biodiversity conservation strategies.

Divergent selection along elevational gradients promotes genetic and phenotypic disparities among small mammal populations.

Species distributed along mountain slopes, facing contrasting habitats in short geographic scale, are of particular interest to test how ecologically based divergent selection promotes phenotypic and genetic disparities as well as to assess isolation-by-environment mechanisms. Here, we conduct the first broad comparative study of phenotypic variation along elevational gradients, integrating a large array of ecological predictors and disentangling population genetic driver processes. The skull form of nine ecologically distinct species distributed over a large altitudinal range (100-4200 m) was compared to assess whether phenotypic divergence is a common phenomenon in small mammals and whether it shows parallel patterns. We also investigated the relative contribution of biotic (competition and predation) and abiotic parameters on phenotypic divergence via mixed models. Finally, we assessed the population genetic structure of a rodent species (Niviventer confucianus) via analysis of molecular variance and FST along three mountain slopes and tested the isolation-by-environment hypothesis using Mantel test and redundancy analysis. We found a consistent phenotypic divergence and marked genetic structure along elevational gradients; however, the species showed mixed patterns of size and skull shape trends across mountain zones. Individuals living at lower altitudes differed greatly in both phenotype and genotype from those living at high elevations, while middle-elevation individuals showed more intermediate forms. The ecological parameters associated with phenotypic divergence along elevation gradients are partly related to species' ecological and evolutionary constraints. Fossorial and solitary animals are mainly affected by climatic factors, while terrestrial and more gregarious species are influenced by biotic and abiotic parameters. A novel finding of our study is that predator richness emerged as an important factor associated with the intraspecific diversification of the mammalian skull along elevational gradients, a previously overlooked parameter. Population genetic structure was mainly driven by environmental heterogeneity along mountain slopes, with no or a week spatial effect, fitting the isolation-by-environment scenario. Our study highlights the strong and multifaceted effects of heterogeneous steep habitats and ecologically based divergent selective forces in small mammal populations.

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics.

Xenarthrans-anteaters, sloths, and armadillos-have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data.