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Data from: Predicting optimal outcomes in cognitive therapy or interpersonal psychotherapy for depressed individuals using the Personalized Advantage Index approach
Introduction: Although psychotherapies for depression produce equivalent outcomes, individual patients respond differently to different therapies. Predictors of outcome have been identified in the context of randomized trials, but this information has not been used to predict which treatment works best for the depressed individual. In this paper, we aim to replicate a recently developed treatment selection method, using data from an RCT comparing the effects of cognitive therapy (CT) and interpersonal psychotherapy (IPT). Methods: 134 depressed patients completed the pre- and post-treatment BDI-II assessment. First, we identified baseline predictors and moderators. Secondly, individual treatment recommendations were generated by combining the identified predictors and moderators in an algorithm that produces the Personalized Advantage Index (PAI), a measure of the predicted advantage in one therapy compared to the other, using standard regression analyses and the leave-one-out cross-validation approach. Results: We found five predictors (gender, employment status, anxiety, personality disorder and quality of life) and six moderators (somatic complaints, cognitive problems, paranoid symptoms, interpersonal self-sacrificing, attributional style and number of life events) of treatment outcome. The mean average PAI value was 8.9 BDI points, and 63% of the sample was predicted to have a clinically meaningful advantage in one of the therapies. Those who were randomized to their predicted optimal treatment (either CT or IPT) had an observed mean end-BDI of 11.8, while those who received their predicted non-optimal treatment had an end-BDI of 17.8 (effect size for the difference = 0.51). Discussion: Depressed patients who were randomized to their predicted optimal treatment fared much better than those randomized to their predicted non-optimal treatment. The PAI provides a great opportunity for formal decision-making to improve individual patient outcomes in depression. Although the utility of the PAI approach will need to be evaluated in prospective research, this study promotes the development of a treatment selection approach that can be used in regular mental health care, advancing the goals of personalized medicine.
Data from: Large-scale genotyping of highly polymorphic loci by next generation sequencing: how to overcome the challenges to reliably genotype individuals?
Studying the different roles of adaptive genes is still a challenge in evolutionary ecology and requires reliable genotyping of large numbers of individuals. Next-generation sequencing (NGS) techniques enable such large-scale sequencing, but stringent data processing is required. Here, we develop an easy to use methodology to process amplicon-based NGS data and we apply this methodology to reliably genotype four major histocompatibility complex (MHC) loci belonging to MHC class I and II of Alpine marmots (Marmota marmota). Our post-processing methodology allowed us to increase the number of retained reads. The quality of genotype assignment was further assessed using three independent validation procedures. A total of 3069 high-quality MHC genotypes were obtained at four MHC loci for 863 Alpine marmots with a genotype assignment error rate estimated as 0.21%. The proposed methodology could be applied to any genetic system and any organism, except when extensive copy-number variation occurs (that is, genes with a variable number of copies in the genotype of an individual). Our results highlight the potential of amplicon-based NGS techniques combined with adequate post-processing to obtain the large-scale highly reliable genotypes needed to understand the evolution of highly polymorphic functional genes.
Data from: Individual variation, population-specific behaviours, and stochastic processes shape marine migration phenologies
1. The phenology of long distance migrations can influence individual fitness, moderate population dynamics, and regulate the availability of ecosystem services to other trophic levels. Phenology varies within and among populations, and can be influenced by conditions individuals experience both prior to departure and encounter en route. 2. Assessing how intrinsic and extrinsic factors (e.g. individual physical condition vs. environmental conditions) interact to influence variation in migratory phenologies across ecological scales is often limited due to logistical constraints associated with tracking large numbers of individuals from multiple populations simultaneously. 3. We used two natural tags, DNA and otolith microstructure analysis, to estimate the relative influence of individual traits (life history strategy, body size at departure, and growth during migration), population-specific strategies, and interannual variability on the phenology of marine migrations in juvenile sockeye salmon Oncorhynchus nerka. 4. We show that the timing and duration of juvenile sockeye salmon migrations were correlated with both life history strategy and body size, while migration duration was also correlated with departure timing and growth rates during migration. Even after accounting for the effect of individual traits, several populations exhibited distinct migration phenologies. Finally, we observed substantial interannual and residual variation, suggesting stochastic environmental conditions moderate the influence of carry-over effects that develop prior to departure, as well as population-specific strategies. 5. Migratory phenologies are shaped by complex interactions between drivers acting at multiple ecological and temporal scales. Given evidence that intraspecific diversity can stabilize ecological systems, conservation efforts should seek to maintain migratory variation among populations and preserve locally adapted phenotypes; however, variation within populations, which may buffer systems from environmental stochasticity, should also be regularly assessed and preserved.
Data from: Quantifying individual heterogeneity and its influence on life-history trajectories: different methods for different questions and contexts
Heterogeneity among individuals influences the life-history trajectories we observe at the population level because viability selection, selective immigration and emigration processes, and ontogeny change the proportion of individuals with specific trait values with increasing age. Here, we review the two main approaches that have been proposed to account for these processes in life-history trajectories, contrasting how they quantify ontogeny and selection, and proposing ways to overcome some of their limitations. Nearly all existing approaches to model individual heterogeneity assume either a single normal distribution or a priori known groups of individuals. Ontogenetic processes, however, can vary across individuals through variation in life-history tactics. We show the usefulness of describing ontogenetic processes by modelling trajectories with a mixture model that focuses on heterogeneity in life-history tactics. Additionally, most methods examine individual heterogeneity in a single trait, ignoring potential correlations among multiple traits caused by latent common sources of individual heterogeneity. We illustrate the value of using a joint modelling approach to assess the presence of a shared latent correlation and its influence on life-history trajectories. We contrast the strengths and limitations of different methods for different research questions, and we exemplify the differences among methods using empirical data from long-term studies of ungulates.
Data from: Neuromechanical coupling within the human triceps surae and its consequence on individual force sharing strategies
Little is known about the factors that influence the coordination of synergist muscles that act across the same joint, even during single-joint isometric tasks. The overall aim of this study was to determine the nature of the relationship between the distribution of activation and the distribution of force-generating capacity among the three heads of the triceps surae (soleus [SOL], gastrocnemius medialis [GM] and lateralis [GL]). Twenty volunteers performed isometric plantarflexions during which the activation of GM, GL and SOL was estimated using electromyography (EMG). Functional muscle physiological cross-sectional area (PCSA) was estimated using imaging techniques and was considered as an index of muscle-force generating capacity. The distribution of activation and PCSA among the three muscles varied greatly between participants. A significant positive correlation between the distribution of activation and the distribution of PCSA was observed when considering the two bi-articular muscles at intensities ≤50% of the maximal contraction (0.51
Data from: Exploring photosymbiotic ecology of planktic foraminifers from chamber-by-chamber isotopic history of individual foraminifers
Evolution of photosymbiotic ecology is an important adaptation for planktic foraminifers that enhances the ecological advantage of living in oligotrophic oceans. Therefore, detecting photosymbiotic ecology in fossil species is one of the keys to understanding the paleobiodiversity dynamics of planktic foraminifers. Because foraminiferal tests record the ontogenetic history of ecological information in geochemical signatures, analyzing individual geochemical profiles with growth can reveal a species' ecology. This study examined chamber-by-chamber stable isotopes (δ13C and δ18O) of foraminiferal individuals to identify photosymbiotic signals. We observed an ontogenetic δ13C increase of up to 2.4‰, accompanied by relatively stable, negative δ18O, in the symbiotic species Globigerinoides conglobatus and Globigerinoides sacculifer. In contrast, δ13C and δ18O showed significant positive correlation during ontogeny in the asymbiotic species Globorotalia truncatulinoides. These two ecological groups produce contrasting isotopic profiles, thereby allowing us to use our ontogenetic isotopic analyses of individual specimens to identify algal photosymbiosis in fossil foraminifers. The chamber-by-chamber isotope analyses with individual ontogeny have great advantages in analyzing rare species because only one individual is required to describe ontogenetic isotopic history. In addition to photosymbiotic identification, our methods hold great potential to provide new insight into species paleoecological studies such as the ontogenetic history of calcification depth.
Individual and synergistic effects of male external genital traits in sexual selection
Male genital traits exhibit extraordinary inter-specific phenotypic variation. This remarkable and general evolutionary trend is widely considered to be the result of sexual selection. However, we still do not have a good understanding of whether or how individual genital traits function in different competitive arenas (episodes of sexual selection), or how different genital traits may interact to influence competitive outcomes. Here, we use an experimental approach based on high-precision laser phenotypic engineering to address these outstanding questions, focusing on three distinct sets of micron-scale external (non-intromittent) genital spines in male Drosophila kikkawai Burla (Diptera: Drosophilidae). Elimination of the large pair of spines on the male secondary claspers sharply reduced male ability to copulate, yet elimination of the other sets of spines on the primary and secondary claspers had no significant effects on copulation probability. Intriguingly, both the large spines on the secondary claspers and the cluster of spines on the primary claspers were found to independently promote male competitive fertilization success. Moreover, when large and small secondary clasper spines were simultaneously shortened in individual males, these males suffered greater reductions in fertilization success relative to males whose traits were altered individually, providing evidence for synergistic effects of external genital traits on fertilization success. Overall, the results are significant in demonstrating that a given genital trait (the large spines on the secondary claspers) can function in different episodes of sexual selection, and distinct genital traits may interact in sexual selection. The results offer an important contribution to evolutionary biology by demonstrating an understudied selective mechanism, operating via subtle trait interactions in a post-insemination context, by which genital traits may be co-evolving.
Data from: Individual-based analyses reveal limited functional overlap in a coral reef fish community.
1.Detailed knowledge of a species' functional niche is crucial for the study of ecological communities and processes. The extent of niche overlap, functional redundancy and functional complementarity are of particular importance if we are to understand ecosystem processes and their vulnerability to disturbances. 2.Coral reefs are among the most threatened marine systems, and anthropogenic activity is changing the functional composition of reefs. The loss of herbivorous fishes is particularly concerning as the removal of algae is crucial for the growth and survival of corals. Yet, the foraging patterns of the various herbivorous fish species are poorly understood. 3.Using a multidimensional framework, we present novel individual-based analyses of species' realized functional niches, which we apply to a herbivorous coral reef fish community. In calculating niche volumes for 21 species, based on their microhabitat utilization patterns during foraging, and computing functional overlaps, we provide a measurement of functional redundancy or complementarity. Complementarity is the inverse of redundancy and is defined as less than 50% overlap in niche volumes. 4.The analyses reveal extensive complementarity with an average functional overlap of just 15.2%. Furthermore, the analyses divide herbivorous reef fishes into two broad groups. The first group (predominantly surgeonfishes and parrotfishes) comprises species feeding on exposed surfaces and predominantly open reef matrix or sandy substrata, resulting in small niche volumes and extensive complementarity. In contrast, the second group consists of species (predominantly rabbitfishes) that feed over a wider range of microhabitats, penetrating the reef matrix to exploit concealed surfaces of various substratum types. These species show high variation among individuals, leading to large niche volumes, more overlap and less complementarity. 5.These results may have crucial consequences for our understanding of herbivorous processes on coral reefs, as algal removal appears to depend strongly on species-specific microhabitat utilization patterns of herbivores. Furthermore, the results emphasize the capacity of the individual-based analyses to reveal variation in the functional niches of species, even in high diversity systems such as coral reefs, demonstrating its potential applicability to other high-diversity ecosystems.
Data from: Individual and group performance suffers from social niche disruption
<p>The associated article has been retracted over concerns relating to irregularities found in the raw data. Concerns relating to the data can be found in the retraction notice: <a href="https://www.journals.uchicago.edu/doi/abs/10.1086/708066">https://www.journals.uchicago.edu/doi/abs/10.1086/708066</a> </p> <p>The social niche specialization hypothesis predicts that animal personalities emerge as a result of individuals occupying different social niches within a group. Here we track individual personality and performance, and collective performance among groups of social spiders where we manipulated the familiarity of the group members. We show that individual personalities, as measured by consistent individual differences in boldness behavior, strengthen with increasing familiarity, and that these personalities can be disrupted by a change in group membership. Changing group membership negatively impacted both individual and group performance. Individuals in less familiar groups lost weight, and these groups were less successful at performing vital collective tasks. These results provide a mechanism for the evolution of stable social groups by demonstrating that social niche re-establishment carries a steep cost to both individuals and groups. Social niche specialization may therefore provide a potential first step on the path towards more organized social systems.</p>
Data from: Demographic variability and heterogeneity among individuals within and among clonal bacteria strains
Identifying what drives individual heterogeneity has been of long interest to ecologists, evolutionary biologists and biodemographers, because only such identification provides deeper understanding of ecological and evolutionary population dynamics. In natural populations one is challenged to accurately decompose the drivers of heterogeneity among individuals as genetically fixed or selectively neutral. Rather than working on wild populations we present here data from a simple bacterial system in the lab, Escherichia coli. Our system, based on cutting-edge microfluidic techniques, provides high control over the genotype and the environment. It therefore allows to unambiguously decompose and quantify fixed genetic variability and dynamic stochastic variability among individuals. We show that within clonal individual variability (dynamic heterogeneity) in lifespan and lifetime reproduction is dominating at about 82–88%, over the 12–18% genetically (adaptive fixed) driven differences. The genetic differences among the clonal strains still lead to substantial variability in population growth rates (fitness), but, as well understood based on foundational work in population genetics, the within strain neutral variability slows adaptive change, by enhancing genetic drift, and lowering overall population growth. We also revealed a surprising diversity in senescence patterns among the clonal strains, which indicates diverse underlying cell-intrinsic processes that shape these demographic patterns. Such diversity is surprising since all cells belong to the same bacteria species, E. coli, and still exhibit patterns such as classical senescence, non-senescence, or negative senescence. We end by discussing whether similar levels of non-genetic variability might be detected in other systems and close by stating the open questions how such heterogeneity is maintained, how it has evolved, and whether it is adaptive.
Data from: Using a robotic fish to investigate individual differences in social responsiveness in the guppy
Responding towards the actions of others is one of the most important behavioral traits whenever animals of the same species interact. Mutual influences among interacting individuals may modulate the social responsiveness seen and thus makes it often difficult to study the level and individual variation in responsiveness. Here, open-loop biomimetic robots that provide standardized, non-interactive social cues can be a useful tool. These robots are not affected by the live animal's actions but are assumed to still represent valuable and biologically relevant social cues. As this assumption is crucial for the use of biomimetic robots in behavioral studies, we hypothesized (a) that meaningful social interactions can be assumed if live animals maintain individual differences in responsiveness both when interacting with a biomimetic robot and a live partner. Furthermore, to study the level of individual variation in social responsiveness, we hypothesized (b) that individual differences should be maintained over the course of multiple tests with the robot. We investigated the response of live guppies (Poecilia reticulata) when allowed to interact either with a biomimetic open-loop controlled fish robot – 'Robofish' – or a live companion. Furthermore we investigated the responses of live guppies when tested three times with Robofish. We found that live guppies' responses towards Robofish were weaker compared to a live companion, most likely as a result of the non-interactive open-loop behavior of Robofish. Guppies, however, were consistent in their individual responses between a live companion and Robofish and similar individual differences in response towards Robofish were maintained over repeated testing even though habituation to the test environment was detectable. Biomimetic robots like Robofish are therefore a useful tool for the study of social responsiveness in guppies and possibly other small fish species.
Data from: Individual versus pseudo-repeatability in behaviour: lessons from translocation experiments in a wild insect
1. Repeatability represents a key parameter in ecological and evolutionary research. Repeatability is underpinned by developmental plasticity and genetic variation but may become biased upwards by repeatable differences in environments to which individuals respond plastically. The extent of upward bias caused by the latter mechanism (causing "pseudo-repeatability") is important yet rarely investigated in ecological research. 2. We repeatedly assayed a key behaviour (flight initiation distance) affecting longevity in a wild cricket population (Gryllus campestris). We used naturally moving, translocated, and forced-stationary individuals to study bias in repeatability caused by spatial variability in environmental conditions. 3. Our experiments acknowledged that translocations might themselves bias repeatability estimates if animals respond to handling procedures (a necessary component of translocations). Individuals were therefore either (i) repeatedly translocated and assayed, or (ii) assayed at multiple burrows as part of natural movements. This enabled estimation of behavioural variance attributable to individual, burrow, and residual components within each treatment; comparison across treatments addressed whether translocations caused bias. We also calculated repeatability for individuals that forced to be stationary to investigate whether this led to upward biases of repeatability. 4. For adult crickets, individual explained 17.8% versus 17.2%, and burrow 8.7% versus 10.3%, of the behavioural variance in translocated versus natural-movement treatments. Repeatability for forced-stationary adults was 31.1%, thereby demonstrating experimentally that certain study designs bias repeatability upwards. For translocated juveniles, individual explained 10.0% and burrow 6.0% of the variance while in the natural-movement treatment those components could not be separated as juveniles do not switch burrows. Translocations did not lead to detectable biases in behavioural mean or variance. 5. Repeatability was not biased for adults subjected to the natural-movement treatment because individuals were assayed under many different environments, facilitating the separation of individual from burrow effects. Upward bias would have occurred with less optimal sampling schemes: if individuals had been assayed repeatedly at the same burrow. We therefore recommend that translocation experiments are more commonly applied, particularly in stationary species, to ensure the unbiased estimation of repeatability.
Data from: Age-dependent trait variation: the relative contribution of within-individual change, selective appearance and disappearance in a long-lived seabird
1. Within populations, the expression of phenotypic traits typically varies with age. Such age-dependent trait variation can be caused by within-individual change (improvement, senescence, terminal effects) and/or selective (dis)appearance of certain phenotypes among older age classes. 2. In this study we applied two methods (decomposition and mixed-modelling) to attribute age-dependent variation in seven phenological and reproductive traits to within-individual change and selective (dis)appearance, in a long-lived seabird, the common tern (Sterna hirundo). 3. At the population level, all traits, except the probability to breed, improved with age (i.e., phenology advanced and reproductive output increased). Both methods identified within-individual change as the main responsible process, and within individuals, performance improved until age 6-13, before levelling off. In contrast, within individuals, breeding probability decreased to age 10, then levelled off. 4. Effects of selective appearance and disappearance were small, but showed that longer-lived individuals had a higher breeding probability and bred earlier, and that younger recruits performed better throughout life than older recruits in terms of both phenology and reproductive performance. In the year prior to death, individuals advanced reproduction, suggesting terminal investment. 5. The decomposition method attributed more age-dependent trait variation to selective disappearance than the mixed-modelling method: 14-36% versus 0-8%, respectively, which we identify to be due to covariance between rates of within-individual change and selective (dis)appearance leading to biased results from the decomposition method. 6. We conclude that the decomposition method is ideal for visualising processes underlying population change in performance from one age class to the next, but that a mixed-modelling method is required to investigate the significance and relative contribution of age-effects. 7. Considerable variation in the contribution of the different age-processes between the seven phenotypic traits studied, as well as notable differences between species in patterns of age-dependent trait expression, calls for better predictions regarding optimal allocation strategies with age.
Data from: Personality and gonadal development as sources of individual variation in response to GnRH challenge in female great tits
Seasonal timing of reproduction is a key life-history trait, but we know little about the mechanisms underlying individual variation in female endocrine profiles associated with reproduction. In birds, 17β-estradiol is a key reproductive hormone that links brain neuroendocrine mechanisms, involved in information processing and decision making, to downstream mechanisms in the liver, where egg-yolk is produced. Here we test, using a simulated induction of the reproductive system through a GnRH-challenge, whether the ovary of pre-breeding female great tits responds to a brain stimulation by increasing estradiol. We also assess how this response is modified by individual-specific traits like age, ovarian follicle size and personality, using females from lines artificially selected for divergent levels of exploratory behaviour. We show that a GnRH injection leads to a rapid increase in circulating concentrations of estradiol but responses varied among individuals. Females with more developed ovarian follicles showed stronger responses and females from lines selected for fast exploratory behaviour showed stronger increases compared to females from the slow line, indicating a heritable component. This study shows that the response of the ovary to a reproductive stimulation from the brain greatly varies among individuals and that this variation can be attributed to several commonly measured individual traits, which sheds light on the mechanisms shaping heritable endocrine phenotypes.
Data from: Positioning behavior according to individual color variation improves camouflage in novel habitats
Behavior can play a key role in adaptation, especially in novel environments. Here we study how ground-perching grasshoppers that colonized street pavements as novel habitats behaviorally manage their detection rates by predators. We found that grasshoppers positioned themselves aligned with the spaces between adjacent bricks more than expected by chance. By performing a virtual predation experiment, we confirmed that this positioning behavior decreases predation rate. Surprisingly, individuals with a poorer cryptic coloration made greater use of this positioning behavior, while individuals with a better cryptic coloration relied more on background color matching. Additionally, positioning behavior interacted with other anti-predation behaviors: individuals who were positioned on the space between bricks allowed potential predators to get closer before fleeing. These results indicate that these grasshoppers showed adaptive flexibility in camouflage and escape behaviors as a function of both individual and environmental variation. Such behavioral flexibility should allow organisms to cope better with novel environments, which deserves more study especially in the current context of global change.
Data from: Lifetime fitness in wild baboons: tradeoffs and individual heterogeneity in quality
Understanding the evolution of life histories requires information on how life histories vary among individuals, and how such variation predicts individual fitness. Using complete life histories for females in a well-studied population of wild baboons, we tested two non-exclusive hypotheses about the relationships among survival, reproduction, and fitness: the quality hypothesis, which predicts positive correlations between life history traits, mediated by variation in resource acquisition, and the tradeoff hypothesis, which predicts negative correlations between life history traits, mediated by tradeoffs in resource allocation. In support of the quality hypothesis, we found that females with higher rates of offspring survival were themselves better at surviving. Further, after statistically controlling for variation in female quality, we found evidence for two types of tradeoffs: females who produced surviving offspring at a slower rate had longer lifespans than those who produced surviving offspring at a faster rate, and females who produced surviving offspring at a slower rate had a higher overall proportion of offspring survive infancy than females who produced surviving offspring at a faster rate. Importantly, these tradeoffs were evident even when accounting for: (i) the influence of offspring survival on maternal birth rate, (ii) the dependence of offspring survival on maternal survival, and (iii) potential age-related changes in birth rate and/or offspring survival. Our results shed light on why tradeoffs are evident in some populations, while variation in individual quality masks tradeoffs in others.
Data from: We happy few: using structured population models to identify the decisive events in the lives of exceptional individuals
In any population, some individuals make it big: they are among the few that produce many offspring, grow to large size, and so on. What distinguishes the lives of these happy few? We present three approaches for identifying what factors distinguish those "lucky" individuals who come to dominate reproduction in a population without fixed differences between individuals (genotype, site quality, etc.): comparing life-history trajectories for lucky and unlucky individuals and calculating the elasticity of the probability of becoming lucky to perturbations in demographic rates at a given size or a given age. As examples we consider published size-structured integral projection models for the tropical tree Dacrydium elatum and the semiarid shrub Artemisia ordosica and an age-size-structured matrix model for the tropical tree Cedrela ordosica. We find that good fortune (e.g., rapid growth) when small and young matters much more than good fortune when older and larger. Becoming lucky is primarily a matter of surviving while others die. For species with more variable growth (such as Cedrela and Ordosica), it is also a matter of growing fast. We focus on reproductive skew, but our methods are broadly applicable and can be used to investigate how individuals come to be exceptional in any aspect.
Data from: Is telomere length a molecular marker of individual quality? insights from a long-lived bird
1. In wild vertebrates, some individuals survive and reproduce better than others and this has led to the concept of individual quality. Despite its importance when studying ecological processes and life-history trade-offs, measuring individual quality is complex because individuals must be followed during a large part of their life. 2. Recently, telomere biology has been successfully brought into ecology and telomere length has been suggested to be a promising molecular tool to evaluate individual quality in wild vertebrates ('the telomere – individual quality hypothesis'). 3. In this study, we tested this hypothesis in a long-lived species, the Black-browed albatross (Thalassarche melanophrys) by simultaneously measuring telomere length and several potential complementary phenotypic proxies of individual quality in a single year. In addition, we followed the return rate and the reproductive performance of these same albatrosses for a decade. 4. We found that long telomeres were associated with several markers of high individual quality (foraging behaviour, body size, and stress hormone levels). Furthermore, we found that a single measure of telomere length could predict future offspring productivity, for at least several years following telomere measurement (better productivity being associated with longer telomeres). 5. Altogether, these results support the 'telomere – individual quality hypothesis' and suggest that telomere length can be useful to estimate individual quality in long-lived seabirds.
Data from: Reproductive success is driven by local site fidelity despite stronger specialisation by individuals for large scale habitat preference
1. There is widespread evidence that within populations, specialists and generalists can coexist and this is particularly prevalent in marine ecosystems, where foraging specialisations are evident. 2. While individuals may limit niche overlap by consistently foraging in specific areas, site fidelity may also emerge as an artefact of habitat choice but both drivers and fitness consequences of site fidelity are poorly understood. 3. Here we examine an individual metric of site and habitat fidelity, using tracking data collected over 11 years for black-browed albatrosses (Thalassarche melanophris). Fidelity was calculated as the similarity between pairs of foraging zones, quantifying measures for within and between years. Foraging areas were identified using area restricted search, defined as periods during which birds decrease speed and increase turning. 4. Our results demonstrate that birds were considerably more specialised in the habitat in which they forage than the exact location they use within years, and there was a similar pattern between years. However, despite this, it was site fidelity that explained reproductive success. Within a single year, females which were more faithful to a specific location had higher reproductive success than non-specialists and between years there was tendency for both sexes. 5. Our results suggest that black-browed albatrosses are highly faithful in their foraging habitat but it is rather site fidelity that is more clearly associated with reproductive success.
Data from: Individual objective and subjective fixation disparity in near vision
Binocular vision refers to the integration of images in the two eyes for improved visual performance and depth perception. One aspect of binocular vision is the fixation disparity, which is a suboptimal condition in individuals with respect to binocular eye movement control and subsequent neural processing. The objective fixation disparity refers to the vergence angle between the visual axes, which is measured with eye trackers. Subjective fixation disparity is tested with two monocular nonius lines which indicate the physical nonius separation required for perceived alignment. Subjective and objective fixation disparity represent the different physiological mechanisms of motor and sensory fusion, but the precise relation between these two is still unclear. This study measures both types of fixation disparity at viewing distances of 40, 30, and 24 cm while observers fixated a central stationary fusion target. 20 young adult subjects with normal binocular vision were tested repeatedly to investigate individual differences. For heterophoria and subjective fixation disparity, this study replicated that the binocular system does not properly adjust to near targets: outward (exo) deviations typically increase as the viewing distance is shortened. This exo proximity effect—however—was not found for objective fixation disparity, which–on the average–was zero. But individuals can have reliable outward (exo) or inward (eso) vergence errors. Cases with eso objective fixation disparity tend to have less exo states of subjective fixation disparity and heterophoria. In summary, the two types of fixation disparity seem to respond in a different way when the viewing distance is shortened. Motor and sensory fusion–as reflected by objective and subjective fixation disparity–exhibit complex interactions that may differ between individuals (eso versus exo) and vary with viewing distance (far versus near vision).
ScienceDex guides
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These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.