Find research datasets worth reusing
Search datasets from major research repositories and use ShareScore to quickly assess how well each record supports discovery, access, and reuse.
37
datasets available to search
ShareScore release 0.9.0
Dataset results
37 results for “biased sex ratio”
Data from: Sex-biased dispersal is independent of sex ratio in a semiaquatic insect
Open the record for dataset details and reuse information.
Data from: Slower senescence in a wild insect population in years with a more female-biased sex ratio
Open the record for dataset details and reuse information.
Data from: Male biased sex ratio reduces the fecundity of one of three female morphs in a polymorphic damselfly
Open the record for dataset details and reuse information.
Causes and consequences of an unusually male-biased adult sex ratio in an unmanaged feral horse population
Open the record for dataset details and reuse information.
Data from: Replicated origin of female biased adult sex ratio in introduced populations of the Trinidadian guppy (Poecilia reticulata).
Open the record for dataset details and reuse information.
Data for: Female-biased sex ratios in urban centres create a fertility trap in post war Finland
<p>Because sex ratios are a key factor regulating mating success and subsequent fitness both across and within species, there is widespread interest in how population-wide sex ratio imbalances affect marriage markets and the formation of families in human societies. Although most modern cities have more women than men and suffer from low fertility rates, the effects of female-biased sex ratios have garnered less attention than male-biased ratios. Here, we analyze how sex ratios are linked to marriages, reproductive histories, dispersal and urbanization by taking advantage of a natural experiment in which an entire population was forcibly displaced during World War II to other local Finnish populations of varying sizes and sex ratios. Using a discrete time-event generalised linear mixed-effects model, and including factors that change across time, such as annual sex ratio, we show how sex ratios, reproduction, and migration are connected in a female-dominated environment. Young childless women migrated toward urban centers where work was available to women, and away from male-biased rural areas. In such areas where there were more females, women were less likely to start reproduction. Despite this constraint, women showed little flexibility in mate choice, with no evidence for an increase in partner age difference in female-biased areas. We propose that together these behaviours and conditions combine to generate an 'urban fertility trap' which may have important consequences for our understanding of the fertility dynamics of today including the current fertility decline across the developed world.</p>
Data from: Population structure leads to male-biased population sex ratios under environmental sex determination
Spatial structure has been shown to favor female-biased sex allocation, but current theory fails to explain male biases seen in many taxa, particularly those with environmental sex determination (ESD). We present a theory and accompanying individual-based simulation model that demonstrates how population structure leads to male-biased population sex ratios under ESD. Our simulations agree with earlier work showing that the high productivity of female-producing habitats creates a net influx of sex-determining alleles into male-producing habitats, causing larger sex ratio biases and lower productivity in male-producing environments (Harts et al. 2014). In contrast to previous findings, we show that male-biasing habitats disproportionately impact the global sex ratio, resulting in stable male-biased population sex ratios under ESD. The failure to detect a male bias in earlier work can be attributed to small subpopulation sizes leading to local mate competition, a condition unlikely to be met in most ESD systems. Simulations revealed that consistent male biases are expected over a wide range of population structures, environmental conditions, and genetic architectures of sex determination, with male excesses as large as 30 percent under some conditions. Given the ubiquity of genetic structure in natural populations, we predict that modest, enduring male biased allocation should be common in ESD species, a pattern consistent with reviews of ESD sex ratios.
Effects of biases in adult sex ratio and male body condition on the alternative reproductive tactics of a gift-giving spider
<p>This dataset contains raw data from the manuscript entitled "<span>Adult sex ratio and male body condition affect alternative reproductive tactics in a spider", from </span>Daniel Heimerl, Pavla Dudová, Karoline Wacker, Elisa Schenkel, Garance Despréaux, Cristina Tuni, accepted for publication in the journal Behavioral Ecology<span>, </span></p> <p>The study investigates how biases in adult sex ratios can affect mating tactics in a spider. Sex ratio variation can alter the intensity of sexual selection by enhancing competition for mates. Under intense competition males increase their investment in behaviors to outcompete rivals (e.g., fighting). Yet, given that in male-biased environments mating opportunities are rare males may alternatively reduce costly courtship and/or adopt alternative reproductive tactics (ARTs). Males of the spider <i>Pisaura mirabilis</i> adopt different mating tactics, offering females genuine nuptial gifts (prey), nutritionally worthless gifts (prey leftovers) or no gifts.</p> <p>To test whether behavioral shifts between gift tactics are triggered by changes in the competitive environment, we established replicate spider populations under natural conditions (field enclosures) at varying adult sex ratios (male-biased, female-biased and equal) and sampled gift tactics (no gift, genuine and worthless gifts) repeatedly over time. We additionally explored how male individual traits, such as body size and condition, affect the expression of ARTs.</p> <p>In male-biased populations males produced more gifts but of low quality, suggesting competition to trigger increased mating effort to ensure mate acquisition and fertilizations, but through a worthless gift tactic. Production of gifts and of genuine gifts was favored by high body condition, pointing to energetic limitations as being central for male reproductive capacity. We hence highlight two co-existing mechanisms at play to explain ARTs in this system, the competitive social environment where expression of gift tactics is based on optimal-decision making to overcome competition, and a conditional strategy linked to the individual's energetic state.</p>
Data from: Persistence of an extreme male-biased adult sex ratio in a natural population of polyandrous bird
In a number of insects, fishes and birds the conventional sex roles are reversed: males are the main care provider whereas females focus on matings. The reversal of typical sex roles is an evolutionary puzzle, because it challenges the foundations of sex roles, sexual selection and parental investment theory. Recent theoretical models predict that biased parental care may be a response to biased adult sex ratios (ASRs). However, estimating ASR is challenging in natural populations, because males and females often have different detectabilities. Here we use demographic modelling with field data from 2101 individuals, including 579 molecularly sexed offspring, to provide evidence that ASR is strongly male-biased in a polyandrous bird with male-biased care. The model predicts 6.1 times more adult males than females (ASR = 0.860, proportion of males) in the Kentish plover Charadrius alexandrinus. The extreme male-bias is consistent between years, and concordant with experimental results showing strongly biased mating opportunity toward females. Based on these results we conjecture that parental sex role reversal may occur in populations that exhibit extreme male-biased ASR.
Data from: Persistence of an extreme male-biased adult sex ratio in a natural population of polyandrous bird
Open the record for dataset details and reuse information.
Data from: Population structure leads to male-biased population sex ratios under environmental sex determination
Open the record for dataset details and reuse information.
Data from: Artificial selection on ant female caste ratio uncovers a link between female-biased sex ratios and infection by Wolbachia endosymbionts
Open the record for dataset details and reuse information.
Effects of biases in adult sex ratio and male body condition on the alternative reproductive tactics of a gift-giving spider
Open the record for dataset details and reuse information.
Data from: Drivers of sex ratio bias in the eastern bongo: lower inbreeding increases the probability of being born male
Open the record for dataset details and reuse information.
Data for: Female-biased sex ratios in urban centres create a fertility trap in post war Finland
Open the record for dataset details and reuse information.
Data from: Multi-generational response to artificial selection for biased clutch sex ratios in Tigriopus californicus populations
Open the record for dataset details and reuse information.
Male mice lacking Teshl lncRNA exhibit inactivation of Y chromosomal multicopy genes and female distortion-biased sex ratio change in offspring
GEO Series GSE162652. Mus musculus. 6 samples. Type: Expression profiling by high throughput sequencing.
ScienceDex guides
Understand access before you commit
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.