Margaret K Thayer

Abstract Climate change is expected to exert varying effects on different taxa and species, affecting both their abundance and distribution ranges. Previous studies have used climate niche models (CNMs) to estimate shifts in the distribution of insects, without considering whether the effects of climate change may vary depending on their functional traits (nesting strategy, body size, and period of activity). Dung beetles, a taxonomic group characterized by using mammalian dung as their primary source of food (coprophagy), respond differently to temperature fluctuations depending on their nesting strategy and body size. In this study, we used CNMs to estimate shifts in the distribution ranges of 33 species of dung beetles under climate change scenarios (the shared socioeconomic pathways from the IPCC’s Sixth Assessment Report) for the period 2041–2060 in North America and Central America (excluding Canada due to absence of data). Additionally, we analyzed whether the effects of climate change on the distribution ranges of the studied species are significantly different depending on their functional traits. Our results showed that climate change will negatively affect the distribution range of the majority of the studied species by the middle of this century, with contrasting effects depending on their nesting strategy and body size. The smallest species and dwellers showed an increase in their occurrence probabilities and percentage of highly suitable habitats, whereas larger-bodied species and tunnelers showed a decrease in both. We found no significant differences between diurnal and nocturnal species. Our results show that by incorporating key traits related to temperature response and ecosystem function, we can analyze shifts in species distribution ranges more precisely, enabling the identification of patterns across functional categories and predictions about their future.

Protected areas (PAs) are geographical spaces intended to conserve populations, communities, and ecosystems, in which species richness must be maximized, the conserved area must be minimized, and anthropogenic pressure must be reduced. The present study analyzed the representativeness, complementarity, and degree of risk of 25 garter snake species of the genus Thamnophis in the PAs of Mexico. This study proposes that at least 17% of the potential geographic distribution (PGD) of species will be found inside PAs and in areas (Aichi Target 11) with a low human footprint (HF). The PGD of species was associated with the PAs and HF layers to identify where and which species could be at local extirpation risk by human activities. The results indicate that the federal PAs contain 85.2% of the species, while the state PAs contain 77.7% of the species. An average of 13.4% of the PGD of these species is found inside PAs, and two species are found outside. In 13 federal PAs and 10 state PAs, the Thamnophis species present high local extirpation risk from human activities. In total, 37% of species are found in PAs with a medium to very high human footprint; therefore, their persistence could be at local extirpation risk. Compared to other taxa, species of the genus Thamnophis are well represented. However, the PDG of more than half of the species achieves Aichi Target 11.

This study explores the latitudinal diversity gradient (LDG) of wild bees (Hymenoptera: Anthophila) in Chile, a region with diverse climates and geographic isolation. By examining species richness patterns, this research seeks to uncover the key factors influencing these patterns in Chilean bees.We compiled and analysed occurrence records of wild bee species from five families, evaluating species richness across latitudinal gradients. To explain the LDG, we tested hypotheses such as Rapoport's effect, the mid‐domain effect (MDE), source‐sink dynamics, and the Climatic Variability Hypothesis. Additionally, we conducted cluster analyses and beta diversity assessments to identify distinct ecoregions and understand patterns of species turnover and nestedness along these gradients.Our analysis revealed a mid‐latitudinal peak in wild bee species richness around 34° S, consistent with the global bimodal latitudinal gradient for bees. The data did not support MDE predictions, implying that geometric constraints alone cannot explain these patterns. Instead, the positive correlation between latitudinal extent and latitude supports Rapoport's effect, indicating broader environmental tolerances at higher latitudes.Beta diversity analyses showed that species turnover, not nestedness, drives diversity variation along latitudinal gradients, reflecting significant species replacement across latitudes due to changing environmental conditions. Cluster analyses identified distinct wild bee groups corresponding to Northern, Central, and Southern Chile ecoregions, reinforcing substantial shifts in species composition across latitudinal bands.Our findings emphasise the importance of stable climates in supporting high bee species richness and broader environmental tolerances at higher latitudes. Understanding these patterns is vital for predicting biodiversity responses to climate change and guiding conservation strategies, especially in Chile's biodiversity hotspots with high species richness and endemism.

Island ecosystems have significant conservation value owing to their higher endemic biotas. Moreover, studies of regional communities that compare differences in species composition (species dissimilarity) among islands and the mainland suggest that community assembly on islands is different from that on the mainland. However, the uniqueness of island biotic assembly has been little studied at the global scale, nor have phylogenetic information or alien species been considered in these patterns. We evaluate taxonomic and phylogenetic change from one community to the next, focusing on differences in species composition between mainland-mainland (M-M) pairs compared to differences between mainland-island pairs (M-I) and between island-island pairs (I-I), using herpetofauna on islands and adjacent mainland areas worldwide. Our analyses detect greater taxonomic and phylogenetic dissimilarity for M-I and I-I comparisons than predicted by M-M model, indicating different island herpetofauna assembly patterns compared with mainland counterparts across the world. However, this higher M-I dissimilarity has been significantly decreased after considering alien species. Our results provide global evidence on the importance of island biodiversity conservation from the aspect of both the taxonomic and phylogenetic uniqueness of island biotic assembly.

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 assessed changes in fundamental climate‐niche space for lizard and snake species in western North America under modeled climate scenarios to inform natural resource managers of possible shifts in species distributions. We generated eight distribution models for each of 130 snake and lizard species in western North America under six time‐by‐climate scenarios. We combined the highest‐performing models per species into a single ensemble model for each scenario. Maps were generated from the ensemble models to depict climate‐niche space for each species and scenario. Patterns of species richness based on climate suitability and niche shifts were calculated from the projections at the scale of the entire study area and individual states and provinces, from Canada to Mexico. Squamate species' climate‐niche space for the recent‐time climate scenario and published known ranges were highly correlated (r = 0.81). Overall, reptile climate‐niche space was projected to move northward in the future. Sixty‐eight percent of species were projected to expand their current climate‐niche space rather than to shift, contract, or remain stable. Only 8.5% of species were projected to lose climate‐niche space in the future, and these species primarily occurred in Mexico and the southwestern U.S. We found few species were projected to lose all suitable climate‐niche space at the state or province level, although species were often predicted to occupy novel areas, such as at higher elevations. Most squamate species were projected to increase their climate‐niche space in future climate scenarios. As climate niches move northward, species are predicted to cross administrative borders, resulting in novel conservation issues for local landowners and natural resource agencies. However, information on species dispersal abilities, landscape connectivity, biophysical tolerances, and habitat suitability is needed to contextualize predictions relative to realized future niche expansions.

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.

Species are often expected to shift their distributions either poleward or upslope to evade warming climates and colonise new suitable climatic niches. However, from 18‐years of fixed transect monitoring data on 88 species of butterfly in the midwestern United States, we show that butterflies are shifting their centroids in all directions, except towards regions that are warming the fastest (southeast).Butterflies shifted their centroids at a mean rate of 4.87 km year−1. The rate of centroid shift was significantly associated with local climate change velocity (temperature by precipitation interaction), but not with mean climate change velocity throughout the species' ranges.Species tended to shift their centroids at a faster rate towards regions that are warming at slower velocities but increasing in precipitation velocity.Surprisingly, species' thermal niche breadth (range of climates butterflies experience throughout their distribution) and wingspan (often used as metric for dispersal capability) were not correlated with the rate at which species shifted their ranges.We observed high phylogenetic signal in the direction species shifted their centroids. However, we found no phylogenetic signal in the rate species shifted their centroids, suggesting less conserved processes determine the rate of range shift than the direction species shift their ranges.This research shows important signatures of multidirectional range shifts (latitudinal and longitudinal) and uniquely shows that local climate change velocities are more important in driving range shifts than the mean climate change velocity throughout a species' entire range.

AbstractAbstract. neighboring countries. Recently, an increase in biological surveys and access to natural preserves has led to a better understanding of species distributions in Nicaragua and across Central America. Here, we provide new departmental records for three species of didelphid, 18 chiropterans (Phyllostomidae, Molossidae, Vespertilionidae), one geomyid, and one mustelid from 21 sites across the country. This work underscores the need for additional sampling across Nicaragua to fill gaps in the known distribution of many species. This information can facilitate or inform conservation actions in established and proposed preserves in Nicaragua.

Insects are the most diverse group of organisms, but their large number of species and the lack of specialists to study them have made this group particularly vulnerable to the main limitations in biological diversity, such as the Wallacean deficit. This study will contribute to the geographical knowledge of an insect trophic guild that has been widely used as an indicator group, the Scarabaeoidea and Silphidae copro-necrophagous beetles, emphasizing their geographical distribution in two Mexican national parks (Iztaccíhuatl-Popocatepetl and La Malinche) and the intermediate region, which includes sky-island ecosystems in central Mexico. Geographic records of the 32 species that have been previously recorded in the study region were compiled and used to generate potential distribution models aiming to generate potential alpha (species richness) and beta (total beta diversity, nestedness and replacement) diversity maps. The greatest predicted species richness was found between 3,000 and 3,500 m a.s.l. in the study region. Potential species richness ranged from 2 to 24 species. Total beta diversity was low in the study region (mean 0.1), while nestedness was the most important component of beta diversity (0.8). The maximum alpha and beta diversity values were predicted outside the national parks. Consequently, we consider that the studied national parks are not able to protect completely the regional alpha and beta diversities by themselves. Implications for insect conservation: Our results show that the highest alfa and beta diversity values of copro-necrophagous beetles might occur outside the national parks, and a suitable way to protect them could be the Archipelago reserve model as an alternative to protect the regional diversity.