1
|
Meta-analysis shows no consistent evidence for senescence in ejaculate traits across animals. Nat Commun 2024; 15:558. [PMID: 38228708 PMCID: PMC10791739 DOI: 10.1038/s41467-024-44768-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 01/04/2024] [Indexed: 01/18/2024] Open
Abstract
Male reproductive traits such as ejaculate size and quality, are expected to decline with advancing age due to senescence. It is however unclear whether this expectation is upheld across taxa. We perform a meta-analysis on 379 studies, to quantify the effects of advancing male age on ejaculate traits across 157 species of non-human animals. Contrary to predictions, we find no consistent pattern of age-dependent changes in ejaculate traits. This result partly reflects methodological limitations, such as studies sampling a low proportion of adult lifespan, or the inability of meta-analytical approaches to document non-linear ageing trajectories of ejaculate traits; which could potentially lead to an underestimation of senescence. Yet, we find taxon-specific differences in patterns of ejaculate senescence. For instance, older males produce less motile and slower sperm in ray-finned fishes, but larger ejaculates in insects, compared to younger males. Notably, lab rodents show senescence in most ejaculate traits measured. Our study challenges the notion of universal reproductive senescence, highlighting the need for controlled methodologies and a more nuanced understanding of reproductive senescence, cognisant of taxon-specific biology, experimental design, selection pressures, and life-history.
Collapse
|
2
|
Disentangling the causes of temporal variation in the opportunity for sexual selection. Nat Commun 2023; 14:1006. [PMID: 36813810 PMCID: PMC9947164 DOI: 10.1038/s41467-023-36536-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 02/06/2023] [Indexed: 02/24/2023] Open
Abstract
In principle, temporal fluctuations in the potential for sexual selection can be estimated as changes in intrasexual variance in reproductive success (i.e. the opportunity for selection). However, we know little about how opportunity measures vary over time, and the extent to which such dynamics are affected by stochasticity. We use published mating data from multiple species to investigate temporal variation in the opportunity for sexual selection. First, we show that the opportunity for precopulatory sexual selection typically declines over successive days in both sexes and shorter sampling periods lead to substantial overestimates. Second, by utilising randomised null models, we also find that these dynamics are largely explained by an accumulation of random matings, but that intrasexual competition may slow temporal declines. Third, using data from a red junglefowl (Gallus gallus) population, we show that declines in precopulatory measures over a breeding period were mirrored by declines in the opportunity for both postcopulatory and total sexual selection. Collectively, we show that variance-based metrics of selection change rapidly, are highly sensitive to sampling durations, and likely lead to substantial misinterpretation if used as indicators of sexual selection. However, simulations can begin to disentangle stochastic variation from biological mechanisms.
Collapse
|
3
|
Are we failing athletes with recurrent groin pain by focusing on group-level biomechanical analysis of their movement strategies? J Sci Med Sport 2022. [DOI: 10.1016/j.jsams.2022.09.067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
4
|
Movement variability in runners with a current or recent musculoskeletal injury: a systematic review. J Sci Med Sport 2022. [DOI: 10.1016/j.jsams.2022.09.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
5
|
A comparison of isometric, concentric and eccentric rotator cuff exercises in the physiotherapy management of subacromial pain syndrome: feasibility study for a randomised controlled trial. J Sci Med Sport 2022. [DOI: 10.1016/j.jsams.2022.09.090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
6
|
Gluteal muscle size and quality in professional ballet dancers compared to non-dancing athletes. J Sci Med Sport 2022. [DOI: 10.1016/j.jsams.2022.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
7
|
Game-play affects hamstring but not adductor muscle fiber mechanics in elite U20 basketball athletes. J Sci Med Sport 2022. [DOI: 10.1016/j.jsams.2022.09.061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
8
|
Hormone therapy and exercise as interventions for post-menopausal women with greater trochanteric pain syndrome. A randomised clinical trial. J Sci Med Sport 2021. [DOI: 10.1016/j.jsams.2021.09.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
9
|
Cam morphology is associated with early hip OA features in young adult football players with and without hip and groin pain. J Sci Med Sport 2021. [DOI: 10.1016/j.jsams.2021.09.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
10
|
Multi-Copy Gene Family Evolution on the Avian W Chromosome. J Hered 2021; 112:250-259. [PMID: 33758922 DOI: 10.1093/jhered/esab016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/20/2020] [Accepted: 03/19/2021] [Indexed: 12/13/2022] Open
Abstract
The sex chromosomes often follow unusual evolutionary trajectories. In particular, the sex-limited chromosomes frequently exhibit a small but unusual gene content in numerous species, where many genes have undergone massive gene amplification. The reasons for this remain elusive with a number of recent studies implicating meiotic drive, sperm competition, genetic drift, and gene conversion in the expansion of gene families. However, our understanding is primarily based on Y chromosome studies as few studies have systematically tested for copy number variation on W chromosomes. Here, we conduct a comprehensive investigation into the abundance, variability, and evolution of ampliconic genes on the avian W. First, we quantified gene copy number and variability across the duck W chromosome. We find a limited number of gene families as well as conservation in W-linked gene copy number across duck breeds, indicating that gene amplification may not be such a general feature of sex chromosome evolution as Y studies would initially suggest. Next, we investigated the evolution of HINTW, a prominent ampliconic gene family hypothesized to play a role in female reproduction and oogenesis. In particular, we investigated the factors driving the expansion of HINTW using contrasts between modern chicken and duck breeds selected for different female-specific selection regimes and their wild ancestors. Although we find the potential for selection related to fecundity in explaining small-scale gene amplification of HINTW in the chicken, purifying selection seems to be the dominant mode of evolution in the duck. Together, this challenges the assumption that HINTW is key for female fecundity across the avian phylogeny.
Collapse
|
11
|
Sexual selection and personality: Individual and group-level effects on mating behaviour in red junglefowl. J Anim Ecol 2021; 90:1288-1306. [PMID: 33630314 DOI: 10.1111/1365-2656.13454] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 02/01/2021] [Indexed: 11/28/2022]
Abstract
Despite increasing evidence of the importance of repeatable among-individual differences in behaviour (animal personality) in ecology and evolution, little remains known about the role of animal personalities in sexual selection. Here, we present an investigation of the hypothesis that the personalities of individuals and their sexual partners play a role in different episodes of sexual selection, and the extent to which these effects are modulated by the social environment. We first examined how two repeatable behaviours-exploration and boldness-are associated with pre- and postcopulatory sexual selection in male red junglefowl Gallus gallus, using replicate groups across three experimental sex ratio treatments. We further explored how the social environment modulates relationships between male personality and mating performance, and whether mating is assortative or disassortative with respect to exploration or boldness. Finally, we examined behavioural mechanisms linking personality with mating performance. Across all sex ratios, the fastest and slowest exploring males courted females proportionally less, and faster exploring males associated with females more and received more sexual solicitations. In female-biased groups, the fastest and slowest exploring males experienced the highest mating success and lowest sperm competition intensity. Faster exploring males also obtained more mates in female-biased groups when their competitors were, on average, slower exploring, and the proportion of matings obtained by fast-exploring males decreased with the proportion of fast-exploring males in a group, consistent with negative frequency-dependent sexual selection. While boldness did not predict mating performance, there was a tendency for individuals to mate disassortatively with respect to boldness. Collectively, our results suggest that male exploration can play a role in sexual selection, and that sexual selection on personality is complex and contingent on the social environment.
Collapse
|
12
|
Prevalence of early hip OA features on MRI in high-impact athletes. The femoroacetabular impingement and hip osteoarthritis cohort (FORCe) study. Osteoarthritis Cartilage 2021; 29:323-334. [PMID: 33387651 PMCID: PMC8900484 DOI: 10.1016/j.joca.2020.12.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 11/03/2020] [Accepted: 12/21/2020] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To compare early hip osteoarthritis (OA) features on magnetic resonance imaging (MRI) in high-impact athletes with and without hip and/or groin pain, and to evaluate associations between early hip OA features, the International Hip Outcome Tool (iHOT33) and Copenhagen Hip and Groin Outcome Score (HAGOS). DESIGN This case-control study evaluated data of the femoroacetabular impingement and hip osteoarthritis cohort (FORCe). One hundred and eighty-two symptomatic (hip and/or groin pain >6 months and positive flexion-adduction-internal-rotation (FADIR) test) and 55 pain-free high-impact athletes (soccer or Australian football (AF)) without definite radiographic hip OA underwent hip MRI. The Scoring Hip Osteoarthritis with MRI (SHOMRI) method quantified and graded the severity of OA features. Each participant completed the iHOT33 and HAGOS. RESULTS Hip and/or groin pain was associated with higher total SHOMRI (0-96) (mean difference 1.4, 95% CI: 0.7-2.2), labral score (adjusted incidence rate ratio (aIRR) 1.33, 95% CI: 1.1-1.6). Differences in prevalence of cartilage defects, labral tears and paralabral cysts between symptomatic and pain-free participants were inconclusive. There was a lower prevalence of effusion-synovitis in symptomatic participants when compared to pain-free participants (adjusted odds ratio (aOR) 0.46 (95% CI: 0.3-0.8). Early hip OA features were not associated with iHOT33 or HAGOS. CONCLUSIONS A complex and poorly understood relationship exists between hip and/or groin pain and early hip OA features present on MRI in high-impact athletes without radiographic OA. Hip and/or groin pain was associated with higher SHOMRI and labral scores.
Collapse
|
13
|
Temporal dynamics of competitive fertilization in social groups of red junglefowl ( Gallus gallus) shed new light on avian sperm competition. Philos Trans R Soc Lond B Biol Sci 2020; 375:20200081. [PMID: 33070718 PMCID: PMC7661449 DOI: 10.1098/rstb.2020.0081] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2020] [Indexed: 01/28/2023] Open
Abstract
Studies of birds have made a fundamental contribution to elucidating sperm competition processes, experimentally demonstrating the role of individual mechanisms in competitive fertilization. However, the relative importance of these mechanisms and the way in which they interact under natural conditions remain largely unexplored. Here, we conduct a detailed behavioural study of freely mating replicate groups of red junglefowl, Gallus gallus, to predict the probability that competing males fertilize individual eggs over the course of 10-day trials. Remating frequently with a female and mating last increased a male's probability of fertilization, but only for eggs ovulated in the last days of a trial. Conversely, older males, and those mating with more polyandrous females, had consistently lower fertilization success. Similarly, resistance to a male's mating attempts, particularly by younger females, reduced fertilization probability. After considering these factors, male social status, partner relatedness and the estimated state of male extragonadal sperm reserves did not predict sperm competition outcomes. These results shed new light on sperm competition dynamics in taxa such as birds, with prolonged female sperm storage and staggered fertilizations. This article is part of the theme issue 'Fifty years of sperm competition'.
Collapse
|
14
|
The Reproductive Microbiome: An Emerging Driver of Sexual Selection, Sexual Conflict, Mating Systems, and Reproductive Isolation: (Trends in Ecology and Evolution 35, 220-234, 2020). Trends Ecol Evol 2020; 36:98. [PMID: 33234298 DOI: 10.1016/j.tree.2020.10.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
15
|
Reproductive Microbiomes and the Sexual Transmission of Beneficial Microbes: Reply to Lombardo et al. Trends Ecol Evol 2020; 35:964-965. [DOI: 10.1016/j.tree.2020.08.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 08/26/2020] [Accepted: 08/27/2020] [Indexed: 11/17/2022]
|
16
|
Getting more from standard rotator cuff strengthening exercises. Shoulder Elbow 2020; 12:203-211. [PMID: 32565922 PMCID: PMC7285972 DOI: 10.1177/1758573219888829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 09/16/2019] [Accepted: 10/21/2019] [Indexed: 11/17/2022]
Abstract
BACKGROUND A simple modification to standard rotator cuff exercises using an additional resistance band around the scapula has been recommended in the clinical setting, postulated to encourage activation of the posterior scapular stabilisers and increase rotator cuff activation. The aim of this clinical laboratory study was to compare scapular and rotator cuff muscle activation between standard and modified exercises. METHODS Electromyographic data were collected from 10 healthy adults via surface and intramuscular electrodes from the scapular and rotator cuff muscles. Internal and external rotation exercises of the shoulder with the arm abducted to 0°, 45° and 90° were performed using one handheld resistance band (standard) or two bands with the additional band applied to the scapula (modified). RESULTS Activation of the trapezii and rhomboid muscles during the modified exercises at 0° and 45° of abduction was significantly greater when compared to the standard exercises (P < 0.05). No significant differences were found in rotator cuff muscle activation. DISCUSSION Applying resistance to the posterior scapula increases activation of some scapular stabilising muscles particularly in lower ranges of abduction. This study provides preliminary evidence that this simple modification can elicit greater scapular muscle activity, potentially producing enhanced exercise outcomes with minimal additional effort.
Collapse
|
17
|
The Reproductive Microbiome: An Emerging Driver of Sexual Selection, Sexual Conflict, Mating Systems, and Reproductive Isolation. Trends Ecol Evol 2020; 35:220-234. [DOI: 10.1016/j.tree.2019.11.004] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 11/18/2019] [Accepted: 11/19/2019] [Indexed: 01/14/2023]
|
18
|
Abstract
In recent years, the field of sexual selection has exploded, with advances in theoretical and empirical research complementing each other in exciting ways. This perspective piece is the product of a “stock-taking” workshop on sexual selection and sexual conflict. Our aim is to identify and deliberate on outstanding questions and to stimulate discussion rather than provide a comprehensive overview of the entire field. These questions are organized into four thematic sections we deem essential to the field. First we focus on the evolution of mate choice and mating systems. Variation in mate quality can generate both competition and choice in the opposite sex, with implications for the evolution of mating systems. Limitations on mate choice may dictate the importance of direct vs. indirect benefits in mating decisions and consequently, mating systems, especially with regard to polyandry. Second, we focus on how sender and receiver mechanisms shape signal design. Mediation of honest signal content likely depends on integration of temporally variable social and physiological costs that are challenging to measure. We view the neuroethology of sensory and cognitive receiver biases as the main key to signal form and the ‘aesthetic sense’ proposed by Darwin. Since a receiver bias is sufficient to both initiate and drive ornament or armament exaggeration, without a genetically correlated or even coevolving receiver, this may be the appropriate ‘null model’ of sexual selection. Thirdly, we focus on the genetic architecture of sexually selected traits. Despite advances in modern molecular techniques, the number and identity of genes underlying performance, display and secondary sexual traits remains largely unknown. In-depth investigations into the genetic basis of sexual dimorphism in the context of long-term field studies will reveal constraints and trajectories of sexually selected trait evolution. Finally, we focus on sexual selection and conflict as drivers of speciation. Population divergence and speciation are often influenced by an interplay between sexual and natural selection. The extent to which sexual selection promotes or counteracts population divergence may vary depending on the genetic architecture of traits as well as the covariance between mating competition and local adaptation. Additionally, post-copulatory processes, such as selection against heterospecific sperm, may influence the importance of sexual selection in speciation. We propose that efforts to resolve these four themes can catalyze conceptual progress in the field of sexual selection, and we offer potential avenues of research to advance this progress.
Collapse
|
19
|
Differential female sociality is linked with the fine-scale structure of sexual interactions in replicate groups of red junglefowl, Gallus gallus. Proc Biol Sci 2019; 286:20191734. [PMID: 31615354 DOI: 10.1098/rspb.2019.1734] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Recent work indicates that social structure has extensive implications for patterns of sexual selection and sexual conflict. However, little is known about the individual variation in social behaviours linking social structure to sexual interactions. Here, we use network analysis of replicate polygynandrous groups of red junglefowl (Gallus gallus) to show that the association between social structure and sexual interactions is underpinned by differential female sociality. Sexual dynamics are largely explained by a core group of highly social, younger females, which are more fecund and more polyandrous, and thus associated with more intense postcopulatory competition for males. By contrast, less fecund females from older cohorts, which tend to be socially dominant, avoid male sexual attention by clustering together and perching on branches, and preferentially reproduce with dominant males by more exclusively associating and mating with them. Collectively, these results indicate that individual females occupy subtly different social niches and demonstrate that female sociality can be an important factor underpinning the landscape of intrasexual competition and the emergent structure of animal societies.
Collapse
|
20
|
Which factors are predictive of return to play and re-injury following calf muscle strain injury? J Sci Med Sport 2019. [DOI: 10.1016/j.jsams.2019.08.167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
21
|
Does a lumbopelvic stability program improve hopping and landing measures compared to an active control? – a randomised trial. J Sci Med Sport 2019. [DOI: 10.1016/j.jsams.2019.08.209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
22
|
MRI defined intra-articular hip findings are seen in semi-elite football players with and without hip-related pain. J Sci Med Sport 2019. [DOI: 10.1016/j.jsams.2019.08.261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
23
|
Hip-related pain is not associated with bony hip morphology in male and female semi-elite football players. J Sci Med Sport 2019. [DOI: 10.1016/j.jsams.2019.08.262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
24
|
Dynamic phenotypic correlates of social status and mating effort in male and female red junglefowl, Gallus gallus. J Evol Biol 2019; 33:22-40. [PMID: 31529557 PMCID: PMC6972591 DOI: 10.1111/jeb.13541] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 09/10/2019] [Accepted: 09/11/2019] [Indexed: 11/30/2022]
Abstract
Despite widespread evidence that mating and intrasexual competition are costly, relatively little is known about how these costs dynamically change male and female phenotypes. Here, we test multiple hypotheses addressing this question in replicate flocks of red junglefowl (Gallus gallus). First, we test the interrelationships between social status, comb size (a fleshy ornament) and body mass at the onset of a mating trial. While comb size covaried positively with body mass across individuals of both sexes, comb size was positively related to social status in females but not in males. Second, we test for changes within individuals in body mass and comb size throughout the mating trial. Both body mass and comb size declined at the end of a trial in both sexes, suggesting that mating effort and exposure to the opposite sex are generally costly. Males lost more body mass if they (a) were socially subordinate, (b) were chased by other males or (c) mated frequently, indicating that subordinate status and mating are independently costly. Conversely, females lost more body mass if they were exposed to a higher frequency of coerced matings, suggesting costs associated with male sexual harassment and female resistance, although costs of mating per se could not be completely ruled out. Neither competitive nor mating interactions predicted comb size change in either sex. Collectively, these results support the notion that sex‐specific costs associated with social status and mating effort result in differential, sex‐specific dynamics of phenotypic change.
Collapse
|
25
|
Bi-Functional Chicken Immunoglobulin-Like Receptors With a Single Extracellular Domain (ChIR-AB1): Potential Framework Genes Among a Relatively Stable Number of Genes Per Haplotype. Front Immunol 2019; 10:2222. [PMID: 31620133 PMCID: PMC6760009 DOI: 10.3389/fimmu.2019.02222] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 09/02/2019] [Indexed: 11/13/2022] Open
Abstract
The leukocyte receptor complex (LRC) in humans encodes many receptors with immunoglobulin-like (Ig-like) extracellular domains, including the killer Ig-like receptors (KIRs) expressed on natural killer (NK) cells among others, the leukocyte Ig-like receptors (LILRs) expressed on myeloid and B cells, and an Fc receptor (FcR), all of which have important roles in the immune response. These highly-related genes encode activating receptors with positively-charged residues in the transmembrane region, inhibitory receptors with immuno-tyrosine based motifs (ITIMs) in the cytoplasmic tail, and bi-functional receptors with both. The related chicken Ig-like receptors (ChIRs) are almost all found together on a microchromosome, with over 100 activating (A), inhibitory (B), and bi-functional (AB) genes, bearing either one or two extracellular Ig-like domains, interspersed over 500-1,000 kB in the genome of an individual chicken. Sequencing studies have suggested rapid divergence and little overlap between ChIR haplotypes, so we wished to begin to understand their genetics. We chose to use a hybridization technique, reference strand-mediated conformational analysis (RSCA), to examine the ChIR-AB1 family, with a moderate number of genes dispersed across the microchromosome. Using fluorescently-labeled references (FLR), we found that RSCA and sequencing of ChIR-AB1 extracellular exon gave two groups of peaks with mobility correlated with sequence relationship to the FLR. We used this system to examine widely-used and well-characterized experimental chicken lines, finding only one or a few simple ChIR haplotypes for each line, with similar numbers of peaks overall. We found much more complicated patterns from a broiler line from a commercial breeder and a flock of red junglefowl, but trios of parents and offspring from another commercial chicken line show that the complicated patterns are due to heterozygosity, indicating a relatively stable number of peaks within haplotypes of these birds. Some ChIR-AB1 peaks were found in all individuals from the commercial lines, and some of these were shared with red junglefowl and the experimental lines derived originally from egg-laying chickens. Overall, this analysis suggests that there are some simple features underlying the apparent complexity of the ChIR locus.
Collapse
|
26
|
Between session reliability of intramuscular electromyography for segments of gluteus medius and minimus during gait and stepping tasks. J Electromyogr Kinesiol 2019; 47:96-104. [DOI: 10.1016/j.jelekin.2019.05.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 05/19/2019] [Accepted: 05/22/2019] [Indexed: 11/17/2022] Open
|
27
|
Sexual selection in complex communities: Integrating interspecific reproductive interference in structured populations. Evolution 2019; 73:1025-1036. [PMID: 30941751 DOI: 10.1111/evo.13726] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 03/04/2019] [Accepted: 03/12/2019] [Indexed: 01/06/2023]
Abstract
The social structure of populations plays a key role in shaping variation in sexual selection. In nature, sexual selection occurs in communities of interacting species; however, heterospecifics are rarely included in characterizations of social structure. Heterospecifics can influence the reproductive outcomes of intrasexual competition by interfering with intraspecific sexual interactions (interspecific reproductive interference [IRI]). We outline the need for studies of sexual selection to incorporate heterospecifics as part of the social environment. We use simulations to show that classic predictions for the effect of social structure on sexual selection are altered by an interaction between social structure and IRI. This interaction has wide-ranging implications for patterns of sexual conflict and kin-selected reproductive strategies in socially structured populations. Our work bridges the gap between sexual selection research on social structure and IRI, and highlights future directions to study sexual selection in interacting communities.
Collapse
|
28
|
Female novelty and male status dynamically modulate ejaculate expenditure and seminal fluid proteome over successive matings in red junglefowl. Sci Rep 2019; 9:5852. [PMID: 30971704 PMCID: PMC6458113 DOI: 10.1038/s41598-019-41336-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 03/04/2019] [Indexed: 11/16/2022] Open
Abstract
Theory predicts that males will strategically invest in ejaculates according to the value of mating opportunities. While strategic sperm allocation has been studied extensively, little is known about concomitant changes in seminal fluid (SF) and its molecular composition, despite increasing evidence that SF proteins (SFPs) are fundamental in fertility and sperm competition. Here, we show that in male red junglefowl, Gallus gallus, along with changes in sperm numbers and SF investment, SF composition changed dynamically over successive matings with a first female, immediately followed by mating with a second, sexually novel female. The SF proteome exhibited a pattern of both protein depletion and enrichment over successive matings, including progressive increases in immunity and plasma proteins. Ejaculates allocated to the second female had distinct proteomic profiles, where depletion of many SFPs was compensated by increased investment in others. This response was partly modulated by male social status: when mating with the second, novel female, subdominants (but not dominants) preferentially invested in SFPs associated with sperm composition, which may reflect status-specific differences in mating rates, sperm maturation and sperm competition. Global proteomic SF analysis thus reveals that successive matings trigger rapid, dynamic SFP changes driven by a combination of depletion and strategic allocation.
Collapse
|
29
|
Sexual selection in socially-structured, polyandrous populations: Some insights from the fowl. ADVANCES IN THE STUDY OF BEHAVIOR 2019. [DOI: 10.1016/bs.asb.2019.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
|
30
|
Variations in lumbar spine joint moments in Australian Rules Football players with a history of hamstring injury. J Sci Med Sport 2018. [DOI: 10.1016/j.jsams.2018.09.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
31
|
Calf strain injuries in elite Australian rules football: Epidemiological features, muscles injured and return to play. J Sci Med Sport 2018. [DOI: 10.1016/j.jsams.2018.09.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
32
|
High prevalence of groin pain identified in elite basketball U20s athletes and its impact on function and quality of life. J Sci Med Sport 2018. [DOI: 10.1016/j.jsams.2018.09.201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
33
|
Movement variability improved more with stability exercise than stretching: A randomised controlled trial. J Sci Med Sport 2018. [DOI: 10.1016/j.jsams.2018.09.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
34
|
Male relatedness and familiarity are required to modulate male-induced harm to females in Drosophila. Proc Biol Sci 2018; 284:rspb.2017.0441. [PMID: 28794215 PMCID: PMC5563793 DOI: 10.1098/rspb.2017.0441] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 07/10/2017] [Indexed: 11/12/2022] Open
Abstract
Males compete over mating and fertilization, and often harm females in the process. Inclusive fitness theory predicts that increasing relatedness within groups of males may relax competition and discourage male harm of females as males gain indirect benefits. Recent studies in Drosophila melanogaster are consistent with these predictions, and have found that within-group male relatedness increases female fitness, though others have found no effects. Importantly, these studies did not fully disentangle male genetic relatedness from larval familiarity, so the extent to which modulation of harm to females is explained by male familiarity remains unclear. Here we performed a fully factorial design, isolating the effects of male relatedness and larval familiarity on female harm. While we found no differences in male courtship or aggression, there was a significant interaction between male genetic relatedness and familiarity on female reproduction and survival. Relatedness among males increased female lifespan, reproductive lifespan and overall reproductive success, but only when males were familiar. By showing that both male relatedness and larval familiarity are required to modulate female harm, these findings reconcile previous studies, shedding light on the potential role of indirect fitness effects on sexual conflict and the mechanisms underpinning kin recognition in fly populations.
Collapse
|
35
|
Inbreeding removes sex differences in lifespan in a population of Drosophila melanogaster. Biol Lett 2017; 12:rsbl.2016.0337. [PMID: 27354712 PMCID: PMC4938057 DOI: 10.1098/rsbl.2016.0337] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 06/08/2016] [Indexed: 02/07/2023] Open
Abstract
Sex differences in ageing rates and lifespan are common in nature, and an enduring puzzle for evolutionary biology. One possibility is that sex-specific mortality rates may result from recessive deleterious alleles in ‘unguarded’ heterogametic X or Z sex chromosomes (the unguarded X hypothesis). Empirical evidence for this is, however, limited. Here, we test a fundamental prediction of the unguarded X hypothesis in Drosophila melanogaster, namely that inbreeding shortens lifespan more in females (the homogametic sex in Drosophila) than in males. To test for additional sex-specific social effects, we studied the lifespan of males and females kept in isolation, in related same-sex groups, and in unrelated same-sex groups. As expected, outbred females outlived outbred males and inbreeding shortened lifespan. However, inbreeding-mediated reductions in lifespan were stronger for females, such that lifespan was similar in inbred females and males. We also show that the social environment, independent of inbreeding, affected male, but not female lifespan. In conjunction with recent studies, the present results suggest that asymmetric inheritance mechanisms may play an important role in the evolution of sex-specific lifespan and that social effects must be considered explicitly when studying these fundamental patterns.
Collapse
|
36
|
Education with exercise improves pain and dysfunction in post-menopausal women with greater trochanteric pain syndrome. J Sci Med Sport 2017. [DOI: 10.1016/j.jsams.2017.09.294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
37
|
Assessment of lumbopelvic stability: Beyond a three-point rating scale. J Sci Med Sport 2017. [DOI: 10.1016/j.jsams.2017.09.240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
38
|
Improving balance: Could it influence lumbopelvic stability? J Sci Med Sport 2017. [DOI: 10.1016/j.jsams.2017.09.241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
39
|
Inducing slight hip discomfort reduces hip extension in gait. J Sci Med Sport 2017. [DOI: 10.1016/j.jsams.2017.09.291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
40
|
|
41
|
Cryptic Female Choice: A General Phenomenon. A Reply to Eberhard. Trends Ecol Evol 2017; 32:807. [DOI: 10.1016/j.tree.2017.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 08/11/2017] [Indexed: 11/28/2022]
|
42
|
Pre- and postcopulatory sexual selection favor aggressive, young males in polyandrous groups of red junglefowl. Evolution 2017; 71:1653-1669. [PMID: 28369868 DOI: 10.1111/evo.13242] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 03/18/2017] [Indexed: 12/31/2022]
Abstract
A challenge in evolutionary biology is to understand the operation of sexual selection on males in polyandrous groups, where sexual selection occurs before and after mating. Here, we combine fine-grained behavioral information (>41,000 interactions) with molecular parentage data to study sexual selection in replicated, age-structured groups of polyandrous red junglefowl, Gallus gallus. Male reproductive success was determined by the number of females mated (precopulatory sexual selection) and his paternity share, which was driven by the polyandry of his female partners (postcopulatory sexual selection). Pre- and postcopulatory components of male reproductive success covaried positively; males with high mating success also had high paternity share. Two male phenotypes affected male pre- and postcopulatory performance: average aggressiveness toward rival males and age. Aggressive males mated with more females and more often with individual females, resulting in higher sexual exclusivity. Similarly, younger males mated with more females and more often with individual females, suffering less intense sperm competition than older males. Older males had a lower paternity share even allowing for their limited sexual exclusivity, indicating they may produce less competitive ejaculates. These results show that-in these populations-postcopulatory sexual selection reinforces precopulatory sexual selection, consistently promoting younger and more aggressive males.
Collapse
|
43
|
The contrasting role of male relatedness in different mechanisms of sexual selection in red junglefowl. Evolution 2017; 71:403-420. [PMID: 27925168 PMCID: PMC5324671 DOI: 10.1111/evo.13145] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 11/08/2016] [Indexed: 12/25/2022]
Abstract
In structured populations, competition for reproductive opportunities should be relaxed among related males. The few tests of this prediction often neglect the fact that sexual selection acts through multiple mechanisms, both before and after mating. We performed experiments to study the role of within-group male relatedness across pre- and postcopulatory mechanisms of sexual selection in social groups of red junglefowl, Gallus gallus, in which two related males and one unrelated male competed over females unrelated to all the males. We confirm theoretical expectations that, after controlling for male social status, competition over mating was reduced among related males. However, this effect was contrasted by other sexual selection mechanisms. First, females biased male mating in favor of the unrelated male, and might also favor his inseminations after mating. Second, males invested more-rather than fewer-sperm in postcopulatory competition with relatives. A number of factors may contribute to explain this counterintuitive pattern of sperm allocation, including trade-offs between male investment in pre- versus postcopulatory competition, differences in the relative relatedness of pre- versus postcopulatory competitors, and female bias in sperm utilization in response to male relatedness. Collectively, these results reveal that within-group male relatedness may have contrasting effects in different mechanisms of sexual selection.
Collapse
|
44
|
|
45
|
The efficacy of interventions for improving shoulder proprioception in people with shoulder instability – A systematic review. J Sci Med Sport 2017. [DOI: 10.1016/j.jsams.2017.01.125] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
46
|
Gluteus medius, gluteus minimus and tensor fascia latae are overactive during gait in post-menopausal women with greater trochanteric pain syndrome. J Sci Med Sport 2017. [DOI: 10.1016/j.jsams.2017.01.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
47
|
Gluteal muscle atrophy and fatty deposits increase with advancing hip osteoarthritis. J Sci Med Sport 2017. [DOI: 10.1016/j.jsams.2016.12.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
48
|
The effect of rehabilitation programs on multidirectional instability of the shoulder: A randomized controlled trial. J Sci Med Sport 2017. [DOI: 10.1016/j.jsams.2017.01.222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
49
|
What is the role of isokinetic strength assessment in identifying hamstring muscle strain injury risk in sport? A systematic review and meta-analysis. J Sci Med Sport 2017. [DOI: 10.1016/j.jsams.2017.01.219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
50
|
The Seminal fluid proteome of the polyandrous Red junglefowl offers insights into the molecular basis of fertility, reproductive ageing and domestication. Sci Rep 2016; 6:35864. [PMID: 27804984 PMCID: PMC5090203 DOI: 10.1038/srep35864] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 10/06/2016] [Indexed: 02/03/2023] Open
Abstract
Seminal fluid proteins (SFPs) are emerging as fundamental contributors to sexual selection given their role in post-mating reproductive events, particularly in polyandrous species where the ejaculates of different males compete for fertilisation. SFP identification however remains taxonomically limited and little is known about avian SFPs, despite extensive work on sexual selection in birds. We characterize the SF proteome of the polyandrous Red junglefowl, Gallus gallus, the wild species that gave rise to the domestic chicken. We identify 1,141 SFPs, including proteins involved in immunity and antimicrobial defences, sperm maturation, and fertilisation, revealing a functionally complex SF proteome. This includes a predominant contribution of blood plasma proteins that is conserved with human SF. By comparing the proteome of young and old males with fast or slow sperm velocity in a balanced design, we identify proteins associated with ageing and sperm velocity, and show that old males that retain high sperm velocity have distinct proteome characteristics. SFP comparisons with domestic chickens revealed both qualitative and quantitative differences likely associated with domestication and artificial selection. Collectively, these results shed light onto the functional complexity of avian SF, and provide a platform for molecular studies of fertility, reproductive ageing, and domestication.
Collapse
|