Morgan Hebard

Given the heightened vulnerability of deserts to climate change, this study aims to provide a comprehensive analysis of avian species diversity across ten global deserts to identify distinct diversity gradients and relatedness. Identify the difference from global patterns in avian migratory proportions and the underlying drivers for assessing the vulnerability and resilience of these desert ecosystems. Crowd-sourced avian diversity data of 2374 species from GBIF.org was used as a key analytical tool to study the diversity gradient across the ten major deserts. The variance in correlation patterns between avian ecological and behavioral traits across deserts were analyzed employing data of 1930 common avian species from AVONET. The analysis included comparisons of bird diversity, migratory patterns and trophic niches between Tropic of Cancer (TCan) and Tropic of Capricorn (TCap) deserts. Significant variations in bird diversity among the deserts were found. Deserts near the TCan exhibited higher bird diversity than in TCap deserts. TCan deserts had a higher prevalence of migratory species, facilitated by a broader niche breadth among sedentary species, which reduces niche competition and allows the influx of migratory invertivores. Proportion of migratory birds is higher in TCan deserts due to wider trophic niche but is significantly lower than the global average for the same latitude range. The findings highlight the need for targeted conservation strategies to protect avian diversity in the TCan deserts and mitigate extinction risks in TCap deserts, ensuring the resilience of these critical ecosystems.

Predicting global change effects poses significant challenges due to the intricate interplay between climate change and anthropogenic stressors in shaping ecological communities and their function, such as pest outbreak risk. Termites are ecosystem engineers, yet some pest species are causing worldwide economic losses. While habitat fragmentation seems to drive pest-dominated termite communities, its interaction with climate change effect remains unknown. We test whether climate and habitat fragmentation interactively alter interspecific competition that may limit pest termite risk. Leveraging global termite co-occurrence including 280 pest species, we found that competitively superior termite species (e.g., large bodied) increased in large and continuous habitats solely at high precipitation. While competitive species suppressed pest species globally, habitat fragmentation drove pest termite risk only in humid biomes. Unfortunately, hu- mid tropics have experienced vast forest fragmentation and rainfall reduction over the past decades. These stressors, if not stopped, may drive pest termite risk, potentially via competitive release.

We analysed the wild bee community sampled from 1921 to 2018 at a nature preserve in southern Michigan, USA, to study long-term community shifts in a protected area. During an intensive survey in 1972 and 1973, Francis C. Evans detected 135 bee species. In the most recent intensive surveys conducted in 2017 and 2018, we recorded 90 species. Only 58 species were recorded in both sampling periods, indicating a significant shift in the bee community. We found that the bee community diversity, species richness and evenness were all lower in recent samples. Additionally, 64% of the more common species exhibited a more than 30% decline in relative abundance. Neural network analysis of species traits revealed that extirpation from the reserve was most likely for oligolectic ground-nesting bees and kleptoparasitic bees, whereas polylectic cavity-nesting bees were more likely to persist. Having longer phenological ranges also increased the chance of persistence in polylectic species. Further analysis suggests a climate response as bees in the contemporary sampling period had a more southerly overall distribution compared to the historic community. Results exhibit the utility of both long-term data and machine learning in disentangling complex indicators of bee population trajectories.

Introduction Flower flies (Diptera: Syrphidae; also known as hoverflies) are important pollinators of wild and cultivated plants. Other pollinators such as bees have declined, and many flower flies in Europe and Chile have been documented to be threatened with extinction. The status of other flower fly faunas is currently unknown. Aims/Methods We assessed the rangewide conservation status of flower flies that occur in Northeastern North America where there is a diverse fauna of 323 native species. Over 150,000 records, drawn from a locality database compiled for a recently published field guide, additional museum records, recent field surveys, and citizen science records, informed the assessments. Results We found that a minimum of 11 species are at risk of rangewide extinction, 267 have lower extinction risk, and 45 had insufficient data to assess. Our best estimate is that 4.0% of species are at risk, assuming data-insufficient species are at risk at the same rate as data sufficient species. The range for this estimate is 3.4–17.3% at risk, assuming that none or all data-insufficient species are at risk, respectively. Discussion Factors causing extinction risk in the fauna we studied are poorly known, although habitat destruction likely explains the decline in one species. While at-risk species mostly have saprophagus or brood parasitic larvae, trophic relationships are confounded by phylogeny (the subfamilies Eristalinae and Microdontinae account for most saprophagus or brood parasitic species). The broad geographical ranges of most species likely contributed to the low rate of imperilment. Implications for insect conservation The small percentage of at-risk flower flies in northeastern North America bodes well for the health of ecosystems there. The results contrast with the situation in Europe, underscoring geographic heterogeneity in flower fly conservation status.

Abstract Ninetinae are a group of poorly known spiders that do not fit the image of ‘daddy long-legs spiders’ (Pholcidae), the family to which they belong. They are mostly short-legged, tiny and live in arid environments. The previously monotypic Andean genus Nerudia exemplifies our poor knowledge of Ninetinae: only seven adult specimens from two localities in Chile and Argentina have been reported in the literature. We found representatives of Nerudia at 24 of 52 localities visited in 2019, mostly under rocks in arid habitats, up to 4450 m a.s.l., the highest known record for Pholcidae. With now more than 400 adult specimens, we revise the genus, describing ten new species based on morphology (including SEM) and COI barcodes. We present the first karyotype data for Nerudia and for its putative sister-genus Gertschiola. These two southern South American genera share a X1X2X3Y sex chromosome system. We model the distribution of Nerudia, showing that the genus is expected to occur in the Atacama biogeographic province (no record so far) and that its environmental niche is phylogenetically conserved. This is the first comprehensive revision of any Ninetinae genus. It suggests that focused collecting may uncover a considerable diversity of these enigmatic spiders.

Our understanding of broad-scale biodiversity and functional trait patterns is largely based on plants, and relatively little information is available on soil arthropods. Here, we investigated the distribution of termite diversity globally and morphological traits and diversity across China. Our analyses showed increasing termite species richness with decreasing latitude at both the globally, and within-China. Additionally, we detected obvious latitudinal trends in the mean community value of termite morphological traits on average, with body size and leg length decreasing with increasing latitude. Furthermore, temperature, NDVI and water variables were the most important drivers controlling the variation in termite richness, and temperature and soil properties were key drivers of the geographic distribution of termite morphological traits. Our global termite richness map is one of the first high resolution maps for any arthropod group and especially given the functional importance of termites, our work provides a useful baseline for further ecological analysis.

Throughout the last century, climate change has altered the geographic distributions of many species. Insects, in particular, vary in their ability to track changing climates, and it is likely that phenology is an important determinant of how well insects can either expand or shift their geographic …

Every species experiences limits to its geographic distribution. Some evolutionary models predict that populations at range edges are less well‐adapted to their local environments due to drift, expansion load, or swamping gene flow from the range interior. Alternatively, populations near range edges…

Insects are the focus of many recent studies suggesting population declines, but even invaluable pollination service providers such as bees lack a modern distributional synthesis. Here, we combine a uniquely comprehensive checklist of bee species distributions and >5,800,000 public bee occurrence re…

We provide an annotated checklist of species recorded from caves and other subterranean habitats in the state of Georgia, USA. We report 281 species (228 invertebrates and 53 vertebrates), including 51 troglobionts (cave-obligate species), from more than 150 sites (caves, springs, and wells). Endemism is high; of the troglobionts, 17 (33 % of those known from the state) are endemic to Georgia and seven (14 %) are known from a single cave. We identified three biogeographic clusters of troglobionts. Two clusters are located in the northwestern part of the state, west of Lookout Mountain in Lookout Valley and east of Lookout Mountain in the Valley and Ridge. In addition, there is a group of troglobionts found only in the southwestern corner of the state and associated with the Upper Floridan Aquifer. At least two dozen potentially undescribed species have been collected from caves; clarifying the taxonomic status of these organisms would improve our understanding of cave biodiversity in the state. Conservation concerns related to species found in Georgia caves are significant, with fourteen species (including 13 vertebrates) considered “High Priority Species” under the Georgia State Wildlife Action Plan, many of these species have additional state or federal protections. In addition, 17 invertebrate troglobionts (33 % of those known in the state) are considered “Critically Imperiled” by NatureServe. Several biologically important caves are not protected, these are an important conservation concern. However, remarkably, around one third of all caves in the state are on protected lands, including seven of the eight caves known to host ten or more troglobionts.