Despite many studies showing biodiversity responses to warming, the generality of such responses across taxonomic groups remains unclear. Very few studies have tested for evidence of bryophyte community responses to warming, even though bryophytes are major contributors to diversity and functioning in many ecosystems. Here we report an empirical study comparing long-term change of bryophyte and vascular plant communities in two sites with contrasting long-term warming trends, using “legacy” botanical records as a baseline for comparison with contemporary resurveys. We hypothesized that ecological changes would be greater in sites with a stronger warming trend, and that vascular plant communities, with narrower climatic niches, would be more sensitive than bryophyte communities to climate warming. For each taxonomic group in each site, we quantified the magnitude of changes in species’ distributions along the elevation gradient, species richness, and community composition. We found contrasted temporal changes in bryophyte vs. vascular plant communities, which only partially supported the warming hypothesis. In the area with a stronger warming trend, we found a significant increase of local diversity and beta-diversity for vascular plants, but not for bryophytes. Presence absence data did not provide sufficient power to detect elevational shifts in species distributions. The patterns observed for bryophytes are in accordance with recent literature showing that local diversity can remain unchanged despite strong changes in composition. Regardless of whether one taxon is systematically more or less sensitive to environmental change than another, our results suggest that vascular plants cannot be used as a surrogate for bryophytes in terms of predicting the nature and magnitude of responses to warming. Thus, to assess overall biodiversity responses to global change, abundance data from different taxonomic groups and different community properties need to be synthesized.

Multi-level societies are complex social systems where basic core units associate in a hierarchical manner, allowing animals to adjust group size in response to local conditions. Each tier of multi-level societies may have evolved under different selective pressures and understanding the effect of temporal variation in these pressures may help determine why these types of social systems form. Our goal was to examine the degree of temporal variability in inter-unit associations in a multi-level society of Rwenzori Angolan colobus monkey (Colobus angolensis ruwenzorii), and to determine whether social or ecological factors correlated with association patterns. Using social network analyses, we described the association patterns of 12-13 core units over 21-months and investigated the effect of changes in rainfall, food availability, and inter-unit dispersals. We found that core unit networks were denser and more clustered when fruit was abundant, likely due to reduced food competition. Male dispersals also occurred more at these times, suggesting that greater band cohesion allowed males to prospect for dispersal opportunities. Within the band, we observed the formation of an all-male unit and the transfer of one core unit between clans. Our findings highlight how ecological conditions can influence association patterns, interunit relationships, and ultimately social organization.

Evolutionary theory predicts that infection by a parasite that reduces future host survival or fecundity should select for increased investment in current reproduction. In this study we use the cestode Ligula intestinalis and its intermediate fish host Engraulicypris sardella in Wissman Bay, Lake Nyasa (Tanzania) as a model system. Using data about infection of E. sardella fish hosts by L. intestinalis collected for a period of 10 years, we explored whether parasite infection affects the fecundity of the fish host E. sardella, and whether host reproductive investment has increased at the expense of somatic growth. We found that L. intestinalis had a strong negative effect on the fecundity of its intermediate fish host. For the non-infected fish we observed an increase in relative gonadal weight at maturity over the study period, while size at maturity decreased. These findings suggest that the life history of E. sardella has been shifting towards earlier reproduction. Further studies are warranted to assess whether these changes reflect plastic or evolutionary responses. We also discuss the interaction between parasite and fishery-mediated selection as a possible explanation for the decline of E. sardella stock in the lake. KEYWORDS Life history evolution; African Great Lakes; Lake Nyasa; Usipa; Lake Malawi sardine; Parasite invasion; Environmental change.

The extended phenotype of helical burrowing behavior in animals has evolved independently many times since first appearing after the Cambrian explosion (~540 million years ago). A number of hypotheses have been proposed to explain the evolution of helical burrowing in certain taxa, but no study has searched for a general explanation encompassing all taxa. We reviewed helical burrowing in both extant and extinct animals and from the trace fossil record and compiled from the literature 10 possible hypotheses for why animals construct helical burrows, including our own ideas. Of these, six were post-construction hypotheses—-benefits to the creator or offspring, realized after burrow construction—-and four were construction hypotheses reflecting direct benefits to the creator during construction. We examined the fit of these hypotheses to a total of 21 extant taxa and ichnotaxa representing 59–184 spp. Only two hypotheses—-antipredator, biomechanical advantage—-could not be rejected for any species (possible in 100% of spp.), but six of the hypotheses could not be rejected for most species (possible in 86–100 % of spp.): microclimate buffer, reduced falling sediment (soil), anticrowding, vertical patch, and the above two hypotheses. Four of these six were construction hypotheses, raising the possibility that helical burrowing might have evolved without providing post-construction benefits. Our analysis showed that increased drainage, deposit feeding, microbial farming, and offspring escape could not explain helical burrowing behavior in the majority of taxa (5–48%). Overall, the evidence does not support a general explanation for the evolution of helical burrowing in animals. The function and evolution of the helix as an extended phenotype would seem, at least in some cases, to provide different advantages for different taxa. Although direct tests of many of the hypotheses would be difficult, we nevertheless offer ways to test some of the hypotheses for selected taxa.

Changing climate and growing human impacts are resulting in globally rising temperatures and the widespread loss of habitats. How species will adapt to these changes is not well understood. The Northern Goshawk (Accipiter gentilis) can be found across the Holarctic but is coming under more intense pressure in many places. Studies of recent populations in Finland and Denmark have shown a marked decline in body size of Northern Goshawks over the past century. Here we investigate long-term changes to Norwegian populations of Northern Goshawk by including material from the Middle Ages and Viking Age. We measured 240 skeletons of modern Northern Goshawks from Norway, Sweden, Denmark and Finland, and 89 Medieval Goshawk bones. Our results show that Norwegian and Swedish female Goshawks have decreased in size over the past century, whilst males showed little decline. Medieval female Goshawks were larger than contemporary females. The Viking Age specimens showed little difference to modern populations but appeared smaller than specimens from the Medieval period. A decline in forest habitats and a concomitant shift towards smaller prey likely drove a shift to smaller body size in Northern Goshawks. Our study shows that significant body size changes in birds can occur over relatively short time spans in response to environmental factors, and that these effects can sometimes differ between sexes.

Species distributions are one of the fundamental factors needed for understanding and conserving wildlife. While the IUCN Red List of Threatened Species is the primary applied reference for biodiversity conservation, limitations in data availability and analyses of the distributions of some species may limit accurate threat classification assessments and conservation recommendations. Improving the accuracy of species distributions in light of growing data and analytical methods is a key step to increasing the efficacy of the Red List. In this study, we reassessed the distribution of takin (Budorcas taxicolor tibetana), a large ungulate in Sichuan Province, southwest China , classified by the IUCN as vulnerable. Using species distribution models and reported habitat requirements, we updated the takin distribution map. Our updated distribution range in the study area (79,449km2) was 61.31% of current distribution range (CDR) on the IUCN red list. This reduction was in large part due to the inclusion in the CDR of substantial areas of lowland plains, high human disturbance, and non-forest habitat, which provide no suitable habitat for takin. According to our results, suitable takin habitat covered 18.97% of the CDR, suggesting a substantially over-estimated distribution. However, there are high proportions of habitat (40%) still covered by the nature reserve network, indicating the importance of protected areas (PAs) in conservation threaten species. We recommend that experts apply the basic approach presented herein to update the Red List distributions for more species to increase the accuracy of assessments and resulting conservation applications.

1. The receiver operating characteristic (ROC) and precision-recall (PR) plots have been widely used to evaluate the performances of species distribution models. Plotting ROC/PR curves requires a traditional test set with both presence and absence data (namely PA approach), but species absence data are usually not available in reality. Plotting ROC/PR curves from presence-only data while treating background data as pseudo absence data (namely PO approach) may provide misleading results. 2. In this study we propose a new approach to calibrate the ROC/PR curves from presence and background data with user-provided information on a constant c, namely PB approach. An estimate of c can also be derived from the PB-based ROC/PR plots given that a model with good ability of discrimination is available. We used three virtual species and a real aerial photography to test the effectiveness of the proposed PB-based ROC/PR plots. Different models (or classifiers) were trained from presence and background data with various samples sizes. The ROC/PR curves plotted by PA approach were used to benchmark the curves plotted by PO and PB approaches. 3. Experimental results show that the curves and areas under curves by PB approach are more similar to that by PA approach as compared with PO approach. The PB-based ROC/PR plots also provide highly accurate estimations of c in our experiment. 4. We conclude that the proposed PB-based ROC/PR plots can provide valuable complements to existing model assessment methods, and they also provide an additional way to estimate the constant c (or species prevalence) from presence and background data.

Usually, adaptive phenotypic differentiation is paralleled by genetic divergence between locally adapted populations. However, adaptation can also happen in a scenario of non-significant genetic divergence due to intense gene flow and/or recent differentiation. While this phenomenon is rarely published, findings on incipient ecologically-driven divergence or isolation by adaptation are relatively common, which could confound our understanding about the frequency at which they actually occur in nature. Here, we explore genome-wide traces of divergence between two populations of the lacertid lizard Psammodromus algirus separated by a 600 m elevational gradient. These populations seem to be differentially adapted to their environments despite showing low levels of genetic differentiation (according to previously studies of mtDNA and microsatellite data). We performed a search for outliers (i.e. loci subject to selection) trying to identify specific loci with FST statistics significantly higher than those expected on the basis of overall, genome-wide estimates of genetic divergence. We find that local phenotypic adaptation (in terms of a wide diversity of characters) was not accompanied by genome-wide differentiation, even when we maximized the chances of unveiling such differentiation at particular loci with FST-based outlier detection tests. Instead, our analyses confirmed the lack of differentiation on the basis of more than 70,000 SNPs, which is concordant with a scenario of local adaptation without any degree of isolation by environment. Our results add evidence to previous studies in which local adaptation does not lead to any kind of isolation (or early stages of ecological speciation), but maintains phenotypic divergence despite the lack of a differentiated genomic background.

1. The use of machine learning technologies to process large quantities of remotely-collected audio data is a powerful emerging research tool in ecology and conservation. 2. We applied these methods to a field study of tinamou (Tinamidae) biology in Madre de Dios, Peru, a region expected to have high levels of interspecies competition and niche partitioning as a result of high tinamou alpha diversity. We used autonomous recording units to gather environmental audio over a period of several months at lowland rainforest sites in the Los Amigos Conservation Concession and developed a Convolutional Neural Network-based data processing pipeline to detect tinamou vocalizations in the dataset. 3. The classified acoustic event data are comparable to similar metrics derived from an ongoing camera trapping survey at the same site, and it should be possible to combine the two datasets for future explorations of the target species’ niche space parameters. 4. Here we provide an overview of the methodology used in the data collection and processing pipeline, offer general suggestions for processing large amounts of environmental audio data, and demonstrate how data collected in this manner can be used to answer questions about bird biology.

The maternally-inherited endosymbiont, Wolbachia, is known to alter the reproductive biology of its arthropod hosts for its benefit and can induce both positive and negative fitness effects in many hosts. Here we describe the effects of the maintenance of two distinct Wolbachia infections, one each from supergroups A and B, on the parasitoid host Nasonia vitripennis. We compare the effect of Wolbachia infections on various traits between the uninfected, single A infected, single B infected, and the double infected strains with their cured versions. Contrary to the previous reports, our results suggest that there is a significant cost associated with the maintenance of Wolbachia infections where traits like family size, fecundity, longevity, and rates of male copulation are compromised in Wolbachia infected strains. The double infected and supergroup B infection strains show higher Wolbachia titer than supergroup A. The double infected Wolbachia strain has the most detrimental impact on the host as compared to single infections. Moreover, there is a supergroup-specific negative impact on these wasps as the supergroup B infections elicit the most pronounced negative effects. These findings raise important questions on the mechanism of survival and maintenance of these reproductive parasites in arthropod hosts.

Ecology is broad and relies on several complementary approaches to study the mechanisms driving the distribution and abundance of organisms and their interactions. One of them is citizen science, the co-production of scientific data and knowledge by non-professional scientists, in collaboration with or under the direction of professional scientists. Citizen science has bloomed in the scientific literature over the last decade and is being incrasingly popular. We used a bibliometric analysis to study whether associating the public to ecological research changes the making of ecology and the nature of questions it asks. We analysed keywords and abstracts of 41,105 articles published the last ten years, disentangling CitSci articles (those explicitly referring to citizen science) and non-CitSci articles. Keyword co-occurrence and thematic map analyses revealed that CitSci articles primarily focused on biodiversity and climate change in a more descriptive way than non-CitSci articles which were more likely to address theoretical questions in ecology. Roughly, citizen science in ecology addressed patterns, whereas non participatory research dug further into mechanisms. Biodiversity also appeared as a more central theme in the CitSci corpus, where it was more systematically associated with other keywords. Our study indicates that should the surge of citizen science approaches in ecological scientific literature have change the type of ecological inquiry, this thematic change is marginal. Still, we provide evidence that specific research questions individualized from ecological CitSci thus supporting the view that citizen science is becoming an independent field of investigation, and not only a peculiar methodological approach to ecological research.

With global climates changing rapidly, animals must adapt to new environmental conditions with altered weather and phenology. Key to adapting to these new conditions is adjusting the timing of reproduction to maximize fitness. Using a long-term dataset on a wild population of yellow-bellied marmots (Marmota flaviventer) at the Rocky Mountain Biological Laboratory (RMBL), we investigated how the timing of reproduction changed with changing spring conditions over the past 50 years. Marmots are hibernators with a four-month active season. It is thus crucial to reproduce early enough in the season to have time to prepare for hibernation, but not too early so as snow cover prevents access to food. Importantly, climate change in this area has increased spring temperatures by 5 oC and decreased spring snowpack by 50 cm over the past 50 years. We evaluated how female marmots adjust the timing of their reproduction in response to the changing conditions and estimated the importance of both genetic variance and plasticity in the variation in this timing. We showed that, within a year, the timing of reproduction is not as tightly linked to the date a female emerges from hibernation as previously thought. We reported a positive effect of spring snowpack but not of spring temperature on the timing of reproduction. We found inter-individual variation in the timing of reproduction, including low heritability, but not in its response to changing spring conditions. There was directional selection for earlier pup emergence date since it increased the number and proportion of pups surviving their first winter. Taken together, the timing of marmot reproduction might evolve via natural selection, however, plastic changes will also be extremely important as long as plasticity is not limited. Further, future studies on the marmots should not operate under the assumption that females reproduce immediately following their emergence.

Aim: To test whether the occupancy of shorebirds has changed in the eastern Canadian Arctic, and whether these changes could indicate that shorebird distributions are shifting in response to long-term climate change Location: Foxe Basin and Rasmussen Lowlands, Nunavut, Canada Methods: We used a unique set of observations, made 25 years apart, using general linear models to test if there was a relationship between changes in shorebird species’ occupancy and their Species Temperature Index, a simple version of a species climate envelope. Results: Changes in occupancy and density varied widely across species, with some increasing and some decreasing. This is despite that overall population trends are known to be negative for all of these species, based on surveys during migration. The changes in occupancy that we observed were positively related to the Species Temperature Index, such that the warmer-breeding species appear to be moving into these regions, while colder-breeding species appear to be shifting out of the regions, likely northwards. Main Conclusions: Our results suggest that we should be concerned about declining breeding habitat availability for bird species whose current breeding ranges are centred on higher and colder latitudes.

Animals exhibit variation in their space and time use across an urban-rural gradient. As the top-down influences of apex predators wane due to human-driven declines, landscape level anthropogenic pressures are rising. Human impacts can be analogous to apex predators in that humans can drive increased mortality in both prey species and carnivores, and impact communities through indirect fear effects and food subsidies. Here, we evaluate the time use of a common mesocarnivore across an urban rural gradient, and test whether it is influenced by the intensity of use of a larger carnivore. Using multiple camera-trap surveys, we compared the temporal response of a small carnivore, the raccoon (Procyon lotor), to the larger coyote (Canis latrans) at four sites across Michigan that represented a gradient of pressure from humans. We found that raccoon time use varied by site and was most unique at the rural extreme. Raccoons consistently did not shift their activity pattern in response to coyotes at the site with the highest anthropogenic pressures despite considerable interannual variation, and instead showed the stronger responses to coyotes at more rural sites. Temporal shifts were characterized by raccoons being more diurnal in areas of high coyote activity. We conclude that raccoons do partition time to avoid coyotes. Our results highlight that the variation in raccoon time use across the entirety of the urban-rural gradient needed to be considered, as anthropogenic pressures may dominate and obscure the dynamics of this interaction. In an increasingly anthropocentric world, to understand species interactions, it is imperative that we consider the entire spectrum of human pressures that it may occur within.

Abstract. I made late breeding season (after 1 July) observations of a central California population of Wilson’s Warbler, Cardellina pusilla, over nine breeding seasons. I sighted males in definitive prebasic molt from 4 July in 2007 through 1 September in 1999. Possibly all territorial males molted on their breeding territories, and molt lasted a maximum of 46 days. Following prebasic molt, territorial males engaged in subdued “post molt singing,” which lasted 14 days in one male, but usually no more than seven days, and was last heard on 6 September in 1999. I sighted no female in definitive prebasic molt, nor in bright basic plumage, during the study. Of 12 color-banded females sighted after 22 July, I confirmed 11 had been in late breeding season uniparental brood care. Possibly all resident females not engaged in late uniparental brood care vacated their breeding territories earlier, and before resident males. They presumably underwent prebasic molt at later times and locations not known. Remaining late nesting females must have molted much later than resident males, and likely later than early departing resident females, and at unknown locations. I last sighted uniparental brood tending females still in dull alternate plumage on 26 and 29 August respectively, whereas some males had completed prebasic molt by 13 August. Three unique study findings are the occurrence of male post molt singing, a male/female difference in location of prebasic molt, and a likely dichotomy of prebasic molt timing between females leaving their breeding grounds early, and those remaining in uniparental brood care.

The biodiversity in mountainous ecosystems is high but is threatened by rapid environmental change. Urbanization and other anthropogenic factors in the mountains surrounding cities can affect land use and spatial fragmentation. Moreover, patterns of habitat are closely related to elevation and have a major effect on montane biodiversity. The aim of this study was to analyze the effects of spatial fragmentation on the vertical distribution pattern of bird diversity by characterizing the structure of the bird community, species diversity, and landscape factors at different altitudes. From 2016 to 2019, this study made a four-years continuous monitoring of the breeding biric belts. The result indicated Mount Tai harbored a high bird diversity. Bird richness, abundance and Shannon-Wiener index decreased with latitude in Mount Tai. Moreover, the composition of bird communities varied along altitudinal gradients and supported some special species in different elevational bands. Road density, number of habitat patches, patch density, and the percentage of forest significantly affected bird diversity. The effect of patch density was higher compared with other landscape factors. Sufficient habitat and more patches in the low-mountain belt supported higher bird diversity. The middle-mountain belt and high-mountain belt showed contrasting patterns. Our results highlight the effects of ongoing urbanization and human activities on montane biodiversity and emphasize the need for artificial habitats in the mountains surrounding cities to be managed.

This paper aims to investigate the ecological role of Merlucicius merluccius, Linnaeus, 1758, in the southern and central Tyrrhenian Sea (GSA 10, Resolution GFCM/33/2009/2 General Fisheries Commission for the Mediterranean), analysing ontogenetic diet shift, geographical variations on prey composition and feeding habits. A sample of 734 hake specimens between 6 cm and 73 cm of total length (TL) were collected in 2018. To value the ontogenetic shifts in prey composition, five size-classes were created from the sample and for each class were calculated quantitative feeding indices. The cluster and MDS analysis, based on the % IRI, resulted in three trophic groups of hake size classes. The most abundant preys for small hake (size class I) were the Euphausiids, Stylocheiron longicorne and Mysidacea, while for hake with size over 10.5 cm of TL were crustaceans and fish. Engraulis encrasicolus was the most abundant prey fish for hake, followed by Boops boops and Myctophids. The mesopelagic fauna had a relevant role in the European hake diet in the southern zone. The high presence of Euphausiids, Mysids, Myctophidae and Sternoptychidae in the gut content of juvenile hakes (6-23 cm) showed the importance of organic matter and energy flowed from the mesopelagic environment to the epipelagic. Important is also the presence of decapod crustaceans in hake with size over 36 cm TL considering that our study area includes an important Gulf for the fishing of decapod crustacea.

Aim: Selection within natural communities has mainly been studied along large abiotic gradient, while the selection of individuals within population should occur locally under the play of biotic filter. To better seize the role of the latter, we postulated that the hierarchal nature of environmental selection and the multiple dimension of species trait space needed to be accounted for. Methods: We replicated a natural species richness gradient (from 2 to 16 species) within four contrasted wetlands (bog, fen, meadow, marsh), sampling functional traits from random individuals in communities. Developing a hierarchical distributional modelling, we analyzed the variation of the mean and dispersion of functional trait space at the ecosystem, community and species levels. Key results: We found that the abiotic differences between wetlands, which shaped a plant productivity gradient, selected species in regards with their leaf nutrient conservation / acquisition strategy. Within ecosystems, plant species richness was a strong driver of trait variation among both communities and species. Among communities, it shaped the selection of individuals according to their space occupation and leaf adaptations to light conditions. Demographically, some species used intraspecific trait variation to maintain equally dense populations, while others used it to become dominant in favorable conditions. Main Conclusions: Within ecosystems, variation in biotic conditions selects individuals along functional dimensions that are independent to the ones selected across ecosystems. Because intraspecific variations of light-related traits are related to demographic responses, it offers a way to link the study of species richness and eco-evolutionary dynamics.