Range Of Body Sizes Research Articles

Long‐term tracking reveals the influence of body size and habitat type on the home range of Antillean manatees (Trichechus manatus manatus)

AbstractAntillean manatees (Trichechus manatus manatus) are endangered coastal, marine, and riverine megaherbivores with high environmental plasticity, constrained by tidal and seasonal water level cycles that affect access to food and fresh water. Accurate quantification of the species' habitat requirements, typically achieved through home range (HR) estimation, is required to implement area‐based conservation initiatives. In this study, we used GPS tracking data from 38 wild and captive‐rehabilitated released manatees to estimate HR using autocorrelated kernel density estimators (AKDE) and average time speed. We investigated whether body size, habitat type, sex and behavioural group influence home range size due to energy requirements, resources availability, a scramble‐competitive polygyny mating system, and adaptation to the wild. Eighteen manatees exhibited range‐resident behaviour, with a mean 95% home range of 72.96 km2 (± 218.52) and a median of 10.69 km2. The mean daily speed was estimated to be 13.47 km/day (± 4.16). Home range and body size were positively correlated, consistent with HR allometry theory. Long‐term tracked individuals showed a trend of increasing HR over time. Only four released animals (17.4%) were range‐resident, suggesting that they may need additional time to establish a home range. Individuals using only the marine environment had larger home ranges compared to mixed (marine and estuarine) and estuarine environments, probably due to freshwater availability. Our study contributes to the understanding of the factors driving manatee movement and provides more accurate estimates of area requirements, which can inform the establishment and zoning of marine protected areas.

Body size as a metric for the affordable world

The physical body of an organism serves as a vital interface for interactions with its environment. Here, we investigated the impact of human body size on the perception of action possibilities (affordances) offered by the environment. We found that the body size delineated a distinct boundary on affordances, dividing objects of continuous real-world sizes into two discrete categories with each affording distinct action sets. Additionally, the boundary shifted with imagined body sizes, suggesting a causal link between body size and affordance perception. Intriguingly, ChatGPT, a large language model lacking physical embodiment, exhibited a modest yet comparable affordance boundary at the scale of human body size, suggesting the boundary is not exclusively derived from organism-environment interactions. A subsequent fMRI experiment offered preliminary evidence of affordance processing exclusively for objects within the body size range, but not for those beyond. This suggests that only objects capable of being manipulated are the objects capable of offering affordance in the eyes of an organism. In summary, our study suggests a novel definition of object-ness in an affordance-based context, advocating the concept of embodied cognition in understanding the emergence of intelligence constrained by an organism’s physical attributes.

Body size as a metric for the affordable world.

The physical body of an organism serves as a vital interface for interactions with its environment. Here, we investigated the impact of human body size on the perception of action possibilities (affordances) offered by the environment. We found that the body size delineated a distinct boundary on affordances, dividing objects of continuous real-world sizes into two discrete categories with each affording distinct action sets. Additionally, the boundary shifted with imagined body sizes, suggesting a causal link between body size and affordance perception. Intriguingly, ChatGPT, a large language model lacking physical embodiment, exhibited a modest yet comparable affordance boundary at the scale of human body size, suggesting the boundary is not exclusively derived from organism-environment interactions. A subsequent fMRI experiment offered preliminary evidence of affordance processing exclusively for objects within the body size range, but not for those beyond. This suggests that only objects capable of being manipulated are the objects capable of offering affordance in the eyes of an organism. In summary, our study suggests a novel definition of object-ness in an affordance-based context, advocating the concept of embodied cognition in understanding the emergence of intelligence constrained by an organism's physical attributes.

Geographic differences in body size distributions underlie food web connectance of tropical forest mammals

Understanding variation in food web structure over large spatial scales is an emerging research agenda in food web ecology. The density of predator–prey links in a food web (i.e., connectance) is a key measure of network complexity that describes the mean proportional dietary breadth of species within a food web. Connectance is a critical component of food web robustness to species loss: food webs with lower connectance have been shown to be more susceptible to secondary extinctions. Identifying geographic variation in food web connectance and its drivers may provide insight into community robustness to species loss. We investigated the food web connectance of ground-dwelling tropical forest mammal communities in multiple biogeographic regions to test for differences among regions in food web connectance and to test three potential drivers: primary productivity, contemporary anthropogenic pressure, and variation in mammal body mass distributions reflective of historical extinctions. Mammal communities from fifteen protected forests throughout the Neo-, Afro-, and Asian tropics were identified from systematic camera trap arrays. Predator–prey interaction data were collected from published literature, and we calculated connectance for each community as the number of observed predator–prey links relative to the number of possible predator–prey links. We used generalized linear models to test for differences among regions and to identify the site level characteristics that best predicted connectance. We found that mammal food web connectance varied significantly among continents and that body size range was the only significant predictor. More possible predator–prey links were observed in communities with smaller ranges in body size and therefore sites with smaller body size ranges had higher mean proportional dietary breadth. Specifically, mammal communities in the Neotropics and in Madagascar had significantly higher connectance than mammal communities in Africa. This geographic variation in contemporary mammalian food web structure may be the product of historical extinctions in the Late Quaternary, which led to greater losses of large-bodied species in the Neotropics and Madagascar thus contributing to higher average proportional dietary breadth among the remaining smaller bodied species in these regions.

Description of Saccocoelioides miguelmontesi n. sp. (Digenea: Haploporidae) from characid fishes in the Iguazu River Basin based on morphological and molecular evidence.

Here we describe a new species of the genus Saccocoelioides found parasitizing Astyanax dissimilis Garavello & Sampaio, Psalidodon bifasciatus (Garavello and Sampaio) and Bryconamericus ikaa Casciotta, Almirón & Azpelicueta from the Iguazu National Park, Misiones province, Argentina. Saccocoelioides miguelmontesi n. sp. was studied based on morphological and molecular (28S rDNA and COI mtDNA sequences) data. The COI mtDNA tree indicated that the specimens collected from the three fish hosts are conspecific, with an intragroup p-distance of 0%. The new species shows an intermediate morphological configuration between the diminutive and robust forms described for Saccocoelioides by Curran (2018). Although, in the 28S rDNA tree, it is placed in a well-supported clade with the two robust species analysed (S. elongatus and S. magnus; p-distance of 1 and 2%, respectively), it differs from the robust group by the range of body size, mature egg size, oral and ventral sucker size, sucker ratio, oral sucker to pharynx ratio, and post-cecal or post-testis/body length percentage. Our results led us to redefine the robust group as having eggs shorter or equal in length to the pharynx. Saccocoelioides miguelmontesi n. sp. the 10th species reported from Argentina and the 7th species within the robust group.

Macroecological correlates of richness, body size, and species range size in terrestrial vertebrates across the world

Macroecological correlates of richness, body size, and species range size in terrestrial vertebrates across the world

Geographic gradients in a functional trait: Drivers of body size and size diversity of ground invertebrate communities

AbstractBody size is a key functional trait governing how an animal community transforms resources and conditions into performance, abundance, and fitness. Here we use the National Ecological Observatory Network of pitfall traps to explore how an ecosystem's plant productivity, temperature, and growing season length accounts for the range of body size across 99 ground invertebrate communities. The 19‐fold continental variation in mean body size failed to covary with latitude, while common ordinal subtaxa grew smaller (e.g., myriapods) to larger (e.g., acari) from Puerto Rico to Alaska. Communities with a larger mean size arose when winters were longer and gross primary productivity was high. The diversity of body sizes in a community (measured as the CV) varied ninefold and decreased with latitude (r2 = 0.24) consistently across common orders. Size‐diverse communities were less likely in ecosystems with long winters (suggesting constraints on the time to build, r2 = 0.34) and those with high invertebrate activity (and hence trap catch, r2 = 0.12). Body size distributions thus appeared to arise from conflicting combinations of constraint (i.e., the ability to build large bodies) and performance (utility of large size in surviving long winters). As warming promotes growing season length, populations of larger, rarer individuals may benefit.

Pediatric phantom library constructed from ICRP mesh-type reference computational phantoms (MRCPs)

International Commission on Radiological Protection (ICRP) recently developed the adult and pediatric mesh-type reference computational phantoms (MRCPs) in high-quality/fidelity mesh format, featuring high deformability into various body sizes and poses. Utilizing this feature, the adult MRCPs-based body-size-dependent phantom library was developed for individualized dosimetry. To complete the full phantom library set, the present study produced the pediatric-MRCPs-based body-size-dependent pediatric phantom library. The library comprises a total of 637 phantoms (356 males and 281 females) with varying standing heights and body weights, covering a wide range of body sizes (i.e., including from 1st to 99th percentile height and weight values) for infants, children, and adolescents, offering a realistic representation of body shapes by reflecting ten secondary anthropometric parameters. The phantoms were automatically constructed utilizing automatic deformation program. The dosimetric impact of the library was investigated by calculating organ doses for external exposures to broad parallel photon beams in anterior-posterior direction. Compared with the values of the pediatric MRCPs, significant differences were observed at energies <0.05 MeV, showing larger values for underweight phantom and smaller values for obese phantom. The results highlight the importance of using the pediatric phantom library for accurate dose estimates of individual children with various body sizes.

Characterization of viscerofugal neurons in human colon by retrograde tracing and multi-layer immunohistochemistry.

Viscerofugal neurons (VFNs) have cell bodies in the myenteric plexus and axons that project to sympathetic prevertebral ganglia. In animals they activate sympathetic motility reflexes and may modulate glucose metabolism and feeding. We used rapid retrograde tracing from colonic nerves to identify VFNs in human colon for the first time, using ex vivo preparations with multi-layer immunohistochemistry. Colonic nerves were identified in isolated preparations of human colon and set up for axonal tracing with biotinamide. After fixation, labeled VFN cell bodies were subjected to multiplexed immunohistochemistry for 12 established nerve cell body markers. Biotinamide tracing filled 903 viscerofugal nerve cell bodies (n = 23), most of which (85%) had axons projecting orally before entering colonic nerves. Morphologically, 97% of VFNs were uni-axonal. Of 215 VFNs studied in detail, 89% expressed ChAT, 13% NOS, 13% calbindin, 9% enkephalin, 7% substance P and 0 of 123 VFNs expressed CART. Few VFNs contained calretinin, VIP, 5HT, CGRP, or NPY. VFNs were often surrounded by dense baskets of axonal varicosities, probably reflecting patterns of connectivity; VAChT+ (cholinergic), SP+ and ENK+ varicosities were most abundant around them. Human VFNs were diverse; showing 27 combinations of immunohistochemical markers, 4 morphological types and a wide range of cell body sizes. However, 69% showed chemical coding, axonal projections, soma-dendritic morphology and connectivity similar to enteric excitatory motor neurons. Viscerofugal neurons are present in human colon and show very diverse combinations of features. High proportions express ChAT, consistent with cholinergic synaptic outputs onto postganglionic sympathetic neurons in prevertebral ganglia.

Evaluating immobilisation thresholds and suitability of conductive glove electrodes for largemouth bass electroanaesthesia

Although electroanaesthesia (immobilising fish with weak currents and direct electrode contact for short-term handling and surgeries) is becoming more common, detailed data on electroanaesthesia immobilisation thresholds and potential morphological predictors of such thresholds remain sparse. We administered electroanaesthesia to largemouth bass (Micropterus nigricans) over a large range of body sizes using conductive mesh gloves connected to a power supply with fine-scale current control and real-time output display, noting current strengths at which tetany occurred. We also investigated whether a range of morphological indices were correlated with the currents required to induce tetany as a proxy for electroanaesthesia. Larger fish required stronger currents before tetany was observed, and larger fish were also more likely to fail to reach tetany before the maximum output on the apparatus (30 V) was reached, a finding that was slightly offset by increasing condition factor. Body length was a suitable predictor of the current required to induce tetany; no other morphometric indices examined were superior to length in this regard. However, there was very high variability in current strengths required to induce electroanaesthesia, likely attributable to consistency challenges associated with the use of conductive mesh gloves as electrodes (e.g., location of contact, wear-and-tear on gloves). We explore the implications of our results for applications of electroanaesthesia in the field, and make recommendations for the development and implementation of novel technologies and best practices when using electroanaesthesia on fish.

Feeding Habits and Reproductive Biology of Newly Discovered Endemic Glassfish, Parambassis waikhomi Geetakumari &amp; Basudha, 2012 of Manipur

Parambassis waikhomi Geetakumari &amp; Basudha, 2012, locally called Ngamhai in Manipuri dialect, is carnivorous in nature, mainly feeds on zooplankton, larvae, nymph etc. The alimentary canal of P. waikhomi is short with well demarcated stomach, and villiform teeth in both the jaws. The values of relative gut length (RGL) ranges from 0.44–0.5 for the specimens whose gut length ranges from 24.12–30.6 mm and body size range from 50–70 mm in total length of body. The maximum values of Gonado-somatic index (GSI) for males and females were observed in April i.e., 1.9439 and 10.2976 respectively. The absolute fecundity determined in the size range of 43.52–63.15 mm in total length and 1.51–4.95 g in body weight ranged from 16860 eggs for ovary weight of 0.15g to 55076 eggs for ovary weight of 0.49g. The species generally breed on pre-monsoon (March). These findings will be helpful for aquaculturist and fisheries resource management strategies as this is an endemic potential ornamental species which can be introduced in ornamental fish industries and its popularization to the rest of the world.

3D printed models are an accurate, cost-effective, and reproducible tool for quantifying terrestrial thermal environments

Predicting ecological responses to rapid environmental change has become one of the greatest challenges of modern biology. One of the major hurdles in forecasting these responses is accurately quantifying the thermal environments that organisms experience. The distribution of temperatures available within an organism's habitat is typically measured using data loggers called operative temperature models (OTMs) that are designed to mimic certain properties of heat exchange in the focal organism. The gold standard for OTM construction in studies of terrestrial ectotherms has been the use of copper electroforming which creates anatomically accurate models that equilibrate quickly to ambient thermal conditions. However, electroformed models require the use of caustic chemicals, are often brittle, and their production is expensive and time intensive. This has resulted in many researchers resorting to the use of simplified OTMs that can yield substantial measurement errors. 3D printing offers the prospect of robust, easily replicated, morphologically accurate, and cost-effective OTMs that capture the benefits but alleviate the problems associated with electroforming. Here, we validate the use of OTMs that were 3D printed using several materials across eight lizard species of different body sizes and living in habitats ranging from deserts to tropical forests. We show that 3D printed OTMs have low thermal inertia and predict the live animal's equilibration temperature with high accuracy across a wide range of body sizes and microhabitats. Finally, we developed a free online repository and database of 3D scans (https://www.3dotm.org/) to increase the accessibility of this tool to researchers around the world and facilitate ease of production of 3D printed models. 3D printing of OTMs is generalizable to taxa beyond lizards. If widely adopted, this approach promises greater accuracy and reproducibility in studies of terrestrial thermal ecology and should lead to improved forecasts of the biological impacts of climate change.

Myrmecophagy in lizards: evolutionary and ecological implications

Abstract Myrmecophagy is one of the most common dietary specializations among vertebrates. Ants are an important food resource for many lizard species. Here, we use a large dataset on ant consumption by lizards (345 species, 33 families) to explore evolutionary and ecological correlates of myrmecophagy across the evolutionary history of lizards. Based on literature and previous empirical work, we develop and test the following hypotheses about myrmecophagy: (i) it does not occur randomly across Squamata; it is correlated with (ii) foraging mode, (iii) habitat, (iv) body size, (v) aridity, and/or (vi) species range size. We found that ant ingestion is not distributed randomly in the phylogeny, with higher ingestion concentrated in some Iguania. Myrmecophagy also evolved in Lacertoidea and it is a derived trait with relatively recent origin. Foraging mode, habitat, body size, and aridity do not influence ant ingestion. Species with smaller range sizes show high variability in ant ingestion, whereas lizards with larger ranges tend to eat a lower proportion of ants. This result confirms the general ecological pattern that specialization is more common in narrowly distributed species. We suggest that future studies should also explore dietary specialization more broadly and provide a better taxonomic resolution of ant species in the diet of lizards.

Development of a Novel Artificial Intelligence Tool to Measure Psoas Volumes in Patients with Diffuse Large B Cell Lymphoma

Introduction Sarcopenia is associated with poor outcomes in cancer patients. However, it is poorly defined, and its clinical assessment can be tedious. Studies have shown psoas muscle volume (PV), measured on computed tomography (CT) scans, correlate with validated measures of frailty and clinical outcomes (Yamada Y., et al. 2023), with better predictive value than another frequently used radiological surrogate - the psoas muscle area measured on a single axial cut at the L3 vertebral level. The labor-intensive nature of PV measurement, lack of validated reference ranges, and inter-observer variability has limited its adoption as a marker of sarcopenia. We hence aim to investigate if an artificial intelligence (AI) model can be developed and trained to automate the measurement of PV in patients with diffuse large B cell lymphoma (DLBCL). Methods This was a retrospective cohort study. Consecutive patients with DLBCL treated at our center from 2010 to 2018 were included. For inclusion, patients had to have at least one contrast-enhanced CT scan performed after diagnosis. Patients who only had positron electron tomography (PET) scans were excluded. The CT scan temporally closest to diagnosis was selected for segmentation. Manual full PV segmentation (Figure 1) was performed on axial CT images using a cloud-based annotation tool (https://darwin.v7labs.com/) by two radiologists, encompassing the entire muscle from origin to insertion. The segmentation data from the first 10 patients (650 images) were then used to train an AI model (Ultralytics YOLOv8) to automatically segment the psoas muscles (Figure 1). Segmented psoas muscles on CT imaging were converted to volume measurements using a code. This was calculated for every patient using the metadata of pixel area and slice thickness contained within each unique CT image. Muscle volumes for the entire patient cohort were generated using this machine learning model and correlated with patient age, height, weight, body mass index (BMI), lean body weight (LBW) (Janmahasatian S., et al. 2005) and body surface area (BSA) determined by the Mosteller formula. Correlation was determined using Pearson's correlation coefficient. Results Data from 123 patients were available for analysis. The median age was 62 years (IQR 53.0 - 70.0), with 89 (72.4%) males. 83 (67.5%) patients were Chinese and 27 (22.0%) were Malay. 111 (90.2%) patients had an Eastern Cooperative Oncology Group (ECOG) performance status of ≤1, and 9 (7.3%) patients had a body mass index (BMI) &amp;lt;18kg/m 2. The median weight was 62.6kg (IQR 54.1 - 72.8), median BMI 23.5kg/m 2 (IQR 20.8 - 26.1), median LBW 48.5kg (IQR 40.2 - 54.3) and median BSA 1.69m 2 (IQR 1.53 - 1.83). 7 (7.4%), 18 (19.1%), 8 (8.5%) and 61 (64.9%) patients were stages 1, 2, 3 and 4 at diagnosis, respectively. 56 (45.6%) of patients had an International Prognostic Index (IPI) of ≥3. Psoas volumes for our population were successfully generated using our deep learning model. The model was able to accurately identify the psoas muscle and distinguish it from other intra-abdominal and intra-pelvic tissue, across a range of body and psoas muscle sizes. It was also able to distinguish the psoas from the iliacus within the pelvis. The median PV was 158.27ml (IQR 105.10 -190.71). There were positive correlations between PV and all physical measures analyzed including height (r = 0.60, p &amp;lt; 0.001), weight (r = 0.47, p &amp;lt; 0.001), BMI (r = 0.28, p 0.002), LBW (r = 0.66, p &amp;lt; 0.001), and BSA (r = 0.55, p = &amp;lt;0.001), and a negative correlation between PV and age (r = -0.22, p = 0.015). Conclusion We have developed a novel AI tool that can identify and distinguish the psoas muscle from other tissue on CT scans. The volumes measured by our AI correlate, as expected, positively with all physical indices analyzed, and negatively with age. Further work is required to determine the accuracy and quantify the efficiency of the AI model compared with trained radiologists, as well as to assess if AI-measured PV changes temporally or predicts clinical outcome.

Scaling of fast-start performance and its thermal dependence in mummichog Fundulus heteroclitus.

Fast-start predator-escape performance and its sensitivity to temperature (24, 30, and 36°C) were evaluated in mummichog Fundulus heteroclitus across a range of body sizes spanning YOY to adult (35-68 mm standard length). Mummichogs exhibit isometry of body dimensions and areas of the dorsal and anal fins but negative allometry of the caudal fin area. These scaling relationships are consistent with observed decreases in fast-start angular velocities with increasing body size. Linear velocity, on the contrary, does not vary with size, and both large and small mummichogs are capable of traversing similar distances in a given amount of time. In addition, temperature influences fast-start performance in similar ways over the size range, though the magnitude of the effect varies with size for some performance measures. In general, fast-start performance increases with test temperature, but mummichogs acclimated to warmer temperatures exhibit lower performance at each test temperature. Altogether, our results suggest that mummichogs across the adult size range may suffer decreases in their predator-escape performance as increasing sea temperatures combine with short-term temperature fluctuations in the estuaries these fish occupy.

Revolutionizing the Garment Industry 5.0: Embracing Closed-Loop Design, E-Libraries, and Digital Twins

This study presents an innovative approach for modernizing the garment industry through the fusion of digital human modeling (DHM), virtual modeling for fit sizing, ergonomic body-size data, and e-library resources. The integration of these elements empowers manufacturers to revolutionize their clothing design and production methods, leading to the delivery of unparalleled fit, comfort, and personalization for a wide range of body shapes and sizes. DHM, known for its precision in representing human bodies virtually and integrating anthropometric data, including ergonomic measurements, enhances the shopping experience by providing valuable insights. Consumers gain access to the knowledge necessary for making tailored clothing choices, thereby enhancing the personalization and satisfaction of their shopping experience. The incorporation of e-library resources takes the garment design approach to a data-driven and customer-centric level. Manufacturers can draw upon a wealth of information regarding body-size diversity, fashion trends, and customer preferences, all sourced from e-libraries. This knowledge supports the creation of a diverse range of sizes and styles, promoting inclusivity and relevance. Beyond improving garment fit, this comprehensive integration streamlines design and production processes by reducing the reliance on physical prototypes. This not only enhances efficiency but also contributes to environmental responsibility, fostering a more sustainable and eco-friendly future for the garment industry and embracing the future of fashion, where technology and data converge to create clothing that authentically fits, resonates with consumers, and aligns with the principles of sustainability. This study developed the mobile application integrating with the information in cloud database in order to present the best-suited garment for the user.

Prey body size generates bias for human and avian agents: Cautions for interpreting small game assemblages

Identifying the accumulating agent(s) of small animal assemblages at archaeological sites is challenging given the range of behaviors, skeletal plans, and body sizes of prey species as well as the range of potential predators. Although mammalian carnivores, raptors, and humans are considered typical predators of small game, there are many contexts—especially in island ecosystems—where humans and raptors are the primary agents for small animal assemblages in the absence of mammalian carnivores. Moreover, smaller animals tend to range in body sizes in these geographically restricted ecosystems. This study aims to broadly explore: 1) how small animal body size affects the taphonomic signature(s) of human and avian predation; and 2) how human and avian-generated small game assemblages compare with one another. To investigate these questions, this study compared the resulting taphonomic patterns of small animal predation by raptors and humans using data collected during a controlled-feeding experiment and an observational study, respectively. In the controlled-feeding experiment, deceased laboratory rats (Rattus norvegicus domestica) (50–500 g) were fed to two Milky Eagle Owls (Ketupa lacteus), one King Vulture (Sarcoramphus papa), and two Lappet-Faced Vultures (Torgos tracheliotos). In the observational study, we explored how humans processed various species of small prey ranging in body mass (80–5000 g) by analyzing anthropogenic modifications (i.e., cutmarks, tooth marks, burning). The resulting small animal assemblages were analyzed post-consumption for skeletal element representation, fragmentation and breakage patterns, and bone surface modifications. Results show that small prey body size significantly affects pre-depositional patterning in terms of skeletal element survival, butchering intensities, and cutmark frequencies. Furthermore, our experimentally generated assemblages show that breakage, fragmentation, and element relative abundance patterns can be used to distinguish between human and avian-accumulated assemblages in the archaeological record.

Biological invasions alter the structure of a tropical freshwater food web.

Biological invasions are expected to alter food web structure, but there are limited empirical data directly comparing invaded versus uninvaded food webs, particularly in species-rich, tropical systems. We characterize for the first time the food web of Lake Gatun-a diverse and highly invaded tropical freshwater lake within the Panama Canal. We used stable isotope analysis to reconstruct the trophic structure of the fish community of Lake Gatun and to compare it to that of a minimally invaded reference lake, Lake Bayano. We found significant differences between the trophic structures of these two Neotropical lakes, notably that Lake Gatun's fish community was characterized by a longer food chain, greater isotopic diversity, a broader range of trophic positions and body sizes, and shifts in the isotopic positions of several native taxa relative to Lake Bayano. The degree of isotopic overlap between native and non-native trophic guilds in Lake Gatun was variable, with herbivores exhibiting the lowest (20%-29%) overlap and carnivores the greatest (81%-100%). Overall, our results provide some of the first empirical evidence for the ways in which multiple introduced and native species may partition isotopic space in a species-rich tropical freshwater food web.

Optimizing anidulafungin exposure across a wide adult body size range.

Echinocandins like anidulafungin are first-line therapies for candidemia and invasive candidiasis, but their dosing may be suboptimal in obese patients. Our objective was to quantify anidulafungin exposure in a cohort of adults across a wide body size range to test if body size affects anidulafungin pharmacokinetics (PK). We enrolled 20 adults between the ages of 18 and 80 years, with an equal distribution of patients above and below a body mass index of 30 kg/m2. A single 100-mg dose of anidulafungin was administered, followed by intensive sampling over 72 h. Population PK analysis was used to identify and compare covariates of anidulafungin PK parameters. Monte Carlo simulations were performed to compute the probability of target attainment (PTA) based on alternative dosing regimens. Participants (45% males) had a median (range) age of 45 (21-78) years and a median (range) weight of 82.7 (42.4-208.3) kg. The observed median (range) of AUC0-∞ was 106.4 (51.9, 138.4) mg∙h/L. Lean body weight (LBW) and adjusted body weight (AdjBW) were more influential than weight as covariates of anidulafungin PK parameters. The conventional 100 mg daily maintenance is predicted to have a PTA below 90% in adults with an LBW > 55 kg or an AdjBW > 75 kg. A daily maintenance dose of 150-200 mg is predicted in these heavier adults. Anidulafungin AUC0-∞ declines with increasing body size. A higher maintenance dose will increase the PTA compared to the current approach in obese patients.

Climate change affects the distribution of diversity across marine food webs.

Many studies predict shifts in species distributions and community size composition in response to climate change, yet few have demonstrated how these changes will be distributed across marine food webs. We use Bayesian Additive Regression Trees to model how climate change will affect the habitat suitability of marine fish species across a range of body sizes and belonging to different feeding guilds, each with different habitat and feeding requirements in the northeast Atlantic shelf seas. Contrasting effects of climate change are predicted for feeding guilds, with spatially extensive decreases in the species richness of consumers lower in the food web (planktivores) but increases for those higher up (piscivores). Changing spatial patterns in predator-prey mass ratios and fish species size composition are also predicted for feeding guilds and across the fish assemblage. In combination, these changes could influence nutrient uptake and transformation, transfer efficiency and food web stability, and thus profoundly alter ecosystem structure and functioning.