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.
Animals show among-individual variation in behaviours, including migration behaviours, which are often repeatable across time periods and contexts, commonly termed “personality”. These behaviours can be correlated, forming a behavioural syndrome. In this study, we assessed the repeatability and correlation of different behavioural traits i.e., boldness, exploration and sociality and the link to migration patterns in Atlantic cod juveniles. To do so, we collected repeated measurements within two short-term (three days) and two long-term (two months) intervals of these traits and genotypes of the Pan I locus, which is indirectly correlated to feeding migration patterns in this species. We found that mainly exploration behaviour was repeatable in the short- and long-term intervals, and a trend for the relationship between exploration and the Pan I locus. Boldness and sociality were only repeatable in the second short-term interval indicating a possible development of stability over time and did not show a relation with the Pan I locus. We found no indication of behavioural syndromes among the studied traits. Although we were unable to identify the existence of a migration syndrome for the migratory genotype (Pan IBB), this study is the first one to highlight the existence of a possible link between the personality trait exploration and the migration-linked Pan I locus. This supports the need for further research that should focus on the effect of exploration tendency and other personality traits on cod movement, including the migratory (frontal) ecotype, to develop management strategies based on behavioural units, rather than treating the population as a single homogeneous stock.
Ant societies are primarily composed of females, whereby labor is divided into reproductive and non-reproductive, worker, castes. Workers and reproductive queens can differ greatly in behavior, longevity, physiology, and morphology, but their differences are usually modest relative to the differences relative to males. Males are short-lived, typically do not provide the colony with labor, often look like a different species, and only occur seasonally. It is these differences that have historically led to their neglect in social insect research, but also why they may facilitate novel phenotypic variation – by increasing the phenotypic variability that is available for selection. In this study, worker variation along a size-shape axis corresponded with variation in male-queen size and shape. As worker variation increased within species, so did sexual variation. Across species in two independent genera, sexual size dimorphism correlated with worker polymorphism regardless of whether the ancestral condition was large or small worker/sexual dimorphism. These results, along with mounting molecular data showing that process of queen-worker caste determination has co-opted many genes/pathways from sex determination, lead to the hypothesis that sexual selection and selection on colony-level traits are non-independent and that sexual dimorphism may even have facilitated the evolution of the distinct worker caste.
Interference competition has the potential to alter avian assemblages at long-lasting arid zone waterholes, particularly in a warming world, as more potentially aggressive species frequent these sites to drink. We used camera traps and observational surveys to investigate interference competition between terrestrial avian species at six long-lasting waterholes across three sampling seasons (two summers and one winter) within the MacDonnell Ranges Bioregion in central Australia. The proportion of individuals drinking for each of four dietary classes (granivores, nectarivores, omnivores, and insectivores) was modelled in relation to their abundance in the immediate waterhole habitat, which informed the potential for competition in each season. We then used the temporal overlap estimators to quantify the degree of competition between species at waterholes with species grouped into families (Meliphagidae, Ptilonorhynchidae, Estrildidae, and Rhipiduridae). We found the proportion of individuals drinking at waterholes was greatest during hot and dry periods, suggesting the potential for interference competition is greatest during these times. This was particularly the case for nectarivores where, in hot and dry conditions, the proportion of drinking individuals increased significantly as their abundance also increased in the waterhole habitat. We predicted that subordinate species would alter their activity periods to avoid competitive interactions with meliphagids (honeyeaters), however, we found there was a high degree of temporal overlap between all families sampled across all seasons. These results suggest subordinate species are unlikely to be excluded from long-lasting waterholes by potentially aggressive species, such as honeyeaters. However, some species may face trade-offs between foraging and accessing waterholes to stay hydrated as they shift their activity to avoid the hottest parts of the day during the summer months. Under global warming, extended hot and dry periods will likely create conditions where balancing energy and hydration requirements becomes increasing difficult and results in the loss of body condition.
The evolution of body size, both within and between species, has been long predicted to be influenced by multifarious environmental factors. However, the specific drivers of body size variation have remained difficult to understand because of the wide range of proximate factors that consistently covary with ectotherm body sizes across populations with varying local environmental conditions. Here, we used a widely distributed lizard (Eremias argus) collected from different populations situated across China to assess how climatic conditions and/or available resources at different altitudes shape the geographical patterns of lizard body size across populations. We used body size data from locations differing in altitudes across China to construct linear mixed models to test the relationship between lizard body size and ecological and climate conditions across altitudes. Lizard populations showed significant differences in body size across altitudes. Furthermore, we found that variation in body size among populations was also explained by climatic and seasonal changes along the altitudinal gradient. Specifically, body size decreased with colder and drier environmental conditions at high altitudes, resulting in a reversal of Bergmann’s rule. Limited resources at high altitudes, as measured by net primary productivity, may also constrain body size. Therefore, our study demonstrates that the intraspecific variation in female lizards’ body size may be strongly influenced by multifarious local environments as adaptive plasticity for female organisms to possibly maximise reproductive ecology along geographic clines.
Texas horned lizards (Phrynosoma cornutum) have disappeared from many areas in Texas, especially from urbanized areas, probably in large part due to loss of suitable habitat. Our previous studies have found that horned lizards persist and occur at high densities in some small towns in southern Texas. Nevertheless, this species has continued to decline and disappear from these towns. Long-term data from Kenedy and Karnes City indicate that when study sites experienced significant shrub and vegetation removal horned lizards declined by 79%. We hypothesize this may in part be due to the degradation of the thermal landscape for these lizards. We determined the preferred temperature range (Tset25 −Tset75) of lizards at our study sites and took field measurements of body temperature (Tb). Temperature loggers were also placed in three microhabitats across our study sites. Shrubs and vegetation provided the highest quality thermal environment, especially for about 5 hours midday when temperatures in the open and buried under the surface exceeded the lizards’ critical maximum temperature (CTmax) or were above their preferred temperature range. Horned lizard density was positively related to the thermal quality of the habitat across our sites. Texas horned lizards in these towns require a heterogenous mix of closely spaced microhabitats and especially thermal refugia, such as shrubs and vegetation along fence lines and in open fields. Maintaining thermal refugia is one of the most important and practical conservation actions that can be taken to help small ectotherms persist in human modified landscapes and cope with increasing temperatures due to climate change.
In the Flora of China account (Pan et al. 2001) of Saxifraga mengtzeana Engl. & Irmsch., eight synonyms were attributed to it and one variant, recognised as S. epiphylla Gornall & Ohba, was split from it. This study re-evaluates the taxonomic status of some of the synonyms and of the segregated species in the light of new evidence presented here. Morphological and molecular evidence demonstrate that populations from north-western Yunnan and Sichuan are genetically differentiated from those in south-eastern Yunnan and neighbouring Guangxi. Observations in the field and in cultivation show that the peltate petiole attachment diagnostic of S. mengtzeana var. peltifolia Engl. & Irmsch. is developmentally labile. Similar observations combined with molecular data show that viviparous phenotypes, formerly treated as S. epiphylla, although largely under genetic control, occur sporadically throughout the ranges of both northern and southern taxa. Populations from north-western Yunnan and Sichuan are best recognised as S. geifolia Balf.f., whereas those from south-eastern Yunnan and neighbouring Guangxi are S. mengtzeana. Peltate-leaved variants of the latter are given no status and are relegated to complete synonymy. Viviparous phenotypes of S. mengtzeana are demoted to the rank of forma, as f. epiphylla; analogous phenotypes of S. geifolia are newly described as f. vivipara. Keywords China, Saxifragaceae, Phylogeny, Morphology, Taxonomy
Increased access to genome-wide data provides new opportunities for plant conservation. However, information on neutral genetic diversity in a small number of marker loci can still be valuable because genomic data are not available to most rare plant species. In the hope of bridging the gap between conservation science and practice, we outline how conservation practitioners can more efficiently employ population genetic information in plant conservation. We first review the current knowledge about the within-population genetic variation and among-population differentiation in neutral genetic variation (NGV) and adaptive genetic variation (AGV) in seed plants. We then introduce the estimates of among-population genetic differentiation in quantitative traits (QST) and neutral markers (FST) to plant biology and summarize conservation applications derived from QST–FST comparisons, particularly on how to capture most AGV and NGV on both in-situ and ex-situ programs. Based on a review of published studies, we found that, on average, two and four populations would be needed for woody perennials (n = 18) to capture 99% of neutral and adaptive genetic variation, respectively, whereas four populations would be needed in case of herbaceous perennials (n = 14). On average, QST is about 3.6, 1.5, and 1.1 times greater than FST in woody plants, annuals, and herbaceous perennials, respectively. We suggest using maximum QST rather than average QST among trait comparisons. Hence, conservation and management policies or suggestions based solely on inference on FST could be misleading, particularly in woody species. We recommend conservation managers and practitioners consider this when formulating further conservation and restoration plans for plant species, and for woody species in particular.
Conversion of the North American prairies to cropland remains a prominent threat to grassland bird populations. Yet, a few species nest in these vastly modified systems. The thick-billed longspur (Rhynchophanes mccownii) is an obligate grassland bird whose populations have declined 4% annually during the past 50 years. Thick-billed longspurs historically nested in recently disturbed or sparsely vegetated patches within native mixed-grass prairie, but observations of longspurs in crop fields during the breeding season suggest such fields also provide cues for habitat selection. Maladaptive selection for poor quality habitat may contribute to ongoing declines in longspur populations, but information on thick-billed longspur breeding ecology in crop fields is lacking. We hypothesized that crop fields may function as ecological traps; specifically, we expected that crop fields may provide cues for territory selection but frequent human disturbance and increased exposure to weather and predators would have negative consequences for reproduction. To address this hypothesis, we compared measures of habitat selection (settlement patterns and trends in abundance) and productivity (nest density, nest survival, and number of young fledged) between crop fields and native sites in northeastern Montana, USA. Settlement patterns were similar across site types and occupancy ranged from 0.52 ± 0.17SE to 0.99 ± 0.01 on April 7 and 30, respectively. Early season abundance differed by year and changes in abundance during the breeding season were associated with precipitation-driven vegetation conditions, rather than habitat type. Standardized nest density (0.19 ± 0.27SD nests/plot/hour), the number of young fledged per successful nest (2.9 ± 0.18SE), and nest survival (0.24 ± 0.03 SE; n=222 nests) were similar for crop and native sites. Collectively, the data did not support our hypothesis that crop fields are ecological traps: longspurs did not exhibit a clear preference for cropland and reproductive output was not significantly reduced. Our results indicate that crop fields provide alternative breeding habitat within a human-dominated landscape.
Wolf spiders are typically the most common group of arthropod predators on both lake and marine shorelines, because of the high prey availability in these habitats. However, shores are also harsh environments due to flooding and, in proximity to marine waters, to toxic salinity levels. Here, we describe the spider community, prey availabilities and spider diets between shoreline sites with different salinities, albeit with comparatively small differences (5 vs. 7‰). Despite the small environmental differences, spider communities between low and higher saline sites showed an almost complete species turnover. At the same time, differences in prey availability or spider gut contents did not match changes in spider species composition but rather changed with habitat characteristics within region, where spiders collected at sites with thick wrack beds had a different diet than sites with little wrack. These data suggest that shifts in spider communities are due to habitat characteristics rather than prey availabilities, and the most likely candidate restricting species in high salinity would be saline sensitivity. At the same time, species absences from low-saline habitats remain unresolved.
The Philippine native pig (PhNP) is a unique genetic resource with complex genetics due to multiple ancestries and hybridizations with wild pigs. No prior study has determined the population structure and genetic diversity of PhNPs on multiple islands and provinces, which is essential for establishing conservation priorities. In this study, we explore the population structure and genetic diversity of various PhNP populations in Luzon and the Visayas, Philippines, to identify conservation priorities. We analyzed 157 native pigs representing 7 populations (Benguet (B), Kalinga (K), Nueva Vizcaya, Isabela (I), Quezon (Q), Marinduque (M), and Samar (S)) and 39 pigs of transboundary distribution (Duroc, Large White, Landrace, and Berkshire). The pigs were compared against a panel of 21 ISAG–FAO recommended microsatellite markers. We tested for population structure at the island, administrative region and province levels. Strong genetic differentiation between native and transboundary breeds was confirmed by analysis of molecular variance (Frt: 0.08; F’st: 0.288-0.728), Bayesian clustering (k = 2) and Nei’s DA genetic distance (98% bootstrap support for the PhNP cluster). PhNP exhibited high heterozygosity (Ho: 0.72), a high allele count (Na: 9.24) and a low inbreeding coefficient (Fis: -0.022 to 0.150). Bayesian clustering supported genetic differentiation at the island (k = 2; North Luzon and South Luzon-Visayas cluster), administrative region (k = 4) and population (k= 9) levels. The pairwise F’st between PhNP populations ranged from 0.130 (Q and M) to 0.427 (Q and K), confirming that PhNP populations exhibited sufficient genetic distance to be considered separate populations. This study shows that the seven previously assigned PhNP populations, roughly delimited by provincial origin, are unique genetic units for conservation. Furthermore, the small effective population sizes of B, Q, I, and S (Ne: 5, 17, 24, and 26, respectively) necessitate immediate conservation actions, such as incentivizing the farming of PhNP.
During litter decomposition, part of the water-soluble components of the material dissolve (leach) rapidly into available water in the environment. Studies on litter decomposition that quantify mass-loss from litterbags integrate leaching and mineralization. In contrast to Lind et al. (2022), we believe that correcting for leaching in (terrestrial) litterbags studies such as the Tea Bag Index will result in more uncertainties than it resolves. This is mainly because leaching is a continuous process and because leached material can still be mineralized after leaching. Further, amount of material that potentially leaches from tea is comparable to other litter types. When correcting for leaching, it is key to be specific about the employed method, just like being specific about the study specific definition of decomposition.
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.
Eastern wild turkeys (Meleagris gallopavo silvestris) exhibit social hierarchies wherein dominance is established through agnostic interactions within social groups. When dominant individuals effectively monopolize reproductive opportunities, asynchronous breeding can occur, which may disproportionately influence individual fitness within social groups. For females, higher ranked individuals may witness reproductive advantages associated with earlier nesting than subordinate conspecifics. We evaluated reproductive synchrony within and between presumed social groups of GPS-tagged female eastern wild turkeys by inferring female social rank based on timing of nest initiation. We examined 30 social groups with an average of 7 females per group (range 2 - 15) during 2014-2019 in west-central Louisiana. We found that the estimated number of days between first nest initiation across females within social groups varied between 3-7 days across years, and the number of days between nest attempts was lower for successful than failed attempts. Our findings suggest that social hierarchies may influence reproductive success in female wild turkeys, and we postulate that social constraints could cause variation in timing of nest initiation for females within social groups.
Very little is known about factors determining the assemblage structure of megadiverse polyphagous-herbivore scarab chafers in the tropics (Coleoptera: Scarabaeidae). Here, we examined the composition of Sri Lankan chafer assemblages and investigated whether it is influenced more by the general ecoclimatic situation, macrohabitat, of indetermined stochastic biotic and abiotic factors of each locality. We also explored the influence of the latter on separate lineages and general body size. Based on dedicated field surveys conducted during the dry and wet seasons, we examined 4847 chafer individuals of 105 species sampled using multiple UV-light traps in 11 localities covering different forest types and altitudinal zones. Assemblages were assessed for compositional similarity, species diversity, and abundance within four major eco-spatial partitions: forest types, elevational zones, localities, and macrohabitats. Our results revealed that assemblages were shaped mainly by locality stochastics, and to a minor extent by ecoclimatic conditions. Macrohabitat had little effect on the assemblage composition. This was true for the entire chafer assemblage as well as for all single lineages or different body size classes. However, in medium and large specimens the contrasts between localities were less pronounced, which was not the case for individual lineages of the assemblage. Contrasts of assemblage similarity between localities were much more evident than those for forest types and elevation zones. Significant correlation between species composition and geographic distance was found only for the assemblage of small-bodied specimens. Seasonal change (dry-wet) in species composition was minor and only measurable in a few localities.
Diospyros (Ebenaceae) is a widely distributed genus of trees and shrubs native to tropical and subtropical regions, with numerous species valued for their fruits (persimmons), timber, and medicinal values. However, information regarding their plastomes and chloroplast evolution is scarce. The present study performed comparative genomic and evolutionary analyses on plastomes of 18 accepted Diospyros species, including three newly sequenced ones. Our study showed a highly conserved genomic structure across the species, with plastome size ranging from 157,321 bp (D. jinzaoshi) to 157,934 bp (D. deyangensis). These plastomes encoded 134–138 genes, including 89–91 protein-coding genes, 1–2 pseudogenes (Ψycf1 for all, Ψrps19 for a few), 37 tRNA genes, and 8 rRNA genes. Comparative analysis of Diospyros identified the intergenic regions (trnH-psbA, rps16-trnQ, trnT-psbD, petA-psbJ, trnL-trnF-ndhJ) as the mutational hotspots in these species. Phylogenomic analyses identified three main groups within the genus designated as the evergreen, deciduous, and island groups. The codon usage analysis identified 30 codons with relative synonymous codon usage (RSCU) values greater than 1 and 29 codons ending with A and U bases. A total of three codons (UUA, GCU, and AGA) with highest (RSCU) values were identified as the optimal codons. ENC-plot indicated the significant role of mutational pressure in shaping codon usage, while most protein-coding genes in Diospyros experienced relaxed purifying selection (Ka/Ks < 1). Additionally, the ndhG, rpoC1, and ycf3 genes showed positive selection (Ka/Ks > 1) in the island, deciduous, and both deciduous and evergreen species, respectively. Thus, the results provide a foundation for elaborating Diospyros’s genetic architecture and taxonomy, conserving genetic diversity and enriching genetic resources.
Major aridification events in Australia during the Pliocene may have had significant impact on the distribution and structure of widespread species. To explore the potential impact of Pliocene and Pleistocene climate oscillations we estimated the timing of population fragmentation and past connectivity of the currently isolated but morphologically similar subspecies of the widespread brushtail possum (Trichosurus vulpecula). We use ecological niche modelling (ENM) with the current fragmented distribution of brushtail possum to estimate the environmental envelope of this marsupial. We projected the ENM on models of past climatic conditions in Australia to infer the potential distribution of brushtail possums over six million years. D-loop haplotypes were used to describe population structure. From shotgun sequencing we assembled whole mitochondrial DNA genomes and estimated timing of intraspecific divergence. Our projections of ENMs suggest current possum populations were unlikely to have been in contact during the Pleistocene. Although lowered sea level during glacial periods enabled colonisation of Tasmania, climate fluctuation during this time would not have facilitated gene flow. The most recent common ancestor of sampled intraspecific diversity dates to the early Pliocene when continental aridification caused significant changes to Australian ecology and Trichosurus vulpecula distribution was likely fragmented. Phylogenetic analysis revealed that the subspecies T. v. hypoleucus (koomal; southwest), T. v. arnhemensis (langkurr; north) and T. v. vulpecula (bilda; southeast) correspond to distinct mitochondrial lineages. Despite little phenotypic differentiation, Trichosurus vulpecula populations probably experienced little gene flow with one another since the Pliocene, supporting the recognition of several subspecies and explaining their adaptations to the regional plant assemblages on which they feed.