The effects of inbreeding on sperm morphometry of captive-bred endangered mammals

Canadian Journal of Zoology, Journal Year: 2017, Volume and Issue: 95(8), P. 599 - 606

Published: June 7, 2017

Captive breeding is used for the conservation of endangered species, but inbreeding can result when a small number founders are to establish populations. Inbreeding reduce proportion normal sperm in an ejaculate, may also have effects on size and shape (morphometry). We investigated morphometry black-footed ferrets (Mustela nigripes (Audubon Bachman, 1851)) red wolves (Canis rufus Audubon 1851) from captive programs determine if more inbred males produced poor quality (bulky head, midpiece, short tail). measured head length, width, midpiece tail length 10 each male both species. A negative relationship between variation coefficient (f) was found ferret, suggesting that individuals will reduced genetic phenotypic variation. Analyses indicated width f positive wolf, could faster sperm. These results indicate affects functionally important aspects morphometry, these not be entirely negative.

Language: Английский

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Intramale variation in sperm size: functional significance in a polygynous mammal

PeerJ, Journal Year: 2015, Volume and Issue: 3, P. e1478 - e1478

Published: Dec. 8, 2015

Studies concerning the relationships between sperm size and velocity at intraspecific level are quite limited often yielded contradictory results across animal kingdom. Intramale variation in may represent a meaningful factor to predict velocity, due its relationship with of competition among related taxa. Because phenotype is under post-copulatory sexual selection, we hypothesized that reduced intramale associated competitiveness red deer. Our show low strongly high normal morphology, which turn good predictors male fertility this species. Furthermore, it well known deer variability testicular mass but there knowledge significance phenomenon level, even though reveal interesting processes selection. Thereby, as preliminary result, found absolute testes negatively size. findings suggest strong selective force leading increase function efficiency, new insights into selection mechanisms.

Language: Английский

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Sperm Numbers as a Paternity Guard in a Wild Bird

Cells, Journal Year: 2022, Volume and Issue: 11(2), P. 231 - 231

Published: Jan. 11, 2022

Sperm competition is thought to impose strong selection on males produce competitive ejaculates outcompete rival under mating conditions. Our understanding of how different sperm traits influence fertilization success, however, remains limited, especially in wild populations. Recent literature highlights the importance incorporating multiple ejaculate and pre-copulatory sexually selected analyses aimed at acts traits. However, variation a male's ability gain success may also depend upon range social ecological factors that determine opportunity for events both within outside pair-bond. Here, we test an effect quantity size male reproductive red-back fairy-wren (Malurus melanocephalus) while simultaneously accounting sexual potential socio-ecological correlates success. We found number (i.e., cloacal protuberance volume), but not morphology, was associated with red-backed fairy-wrens. Most notably, large numbers available copulation achieved greater within-pair paternity results suggest use as defensive strategy guard system where there high risk female control copulation. Finally, our work opportunities when examining role determining

Language: Английский

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Selection on sperm size in response to promiscuity and variation in female sperm storage organs

Journal of Evolutionary Biology, Journal Year: 2022, Volume and Issue: 36(1), P. 131 - 143

Published: Nov. 10, 2022

Abstract Sperm cells are exceptionally morphologically diverse across taxa. However, morphology can be quite uniform within species, particularly for species where females copulate with many males per reproductive bout. Strong sexual selection in these promiscuous is widely hypothesized to reduce intraspecific sperm variation. Conversely, we hypothesize that size variation may maintained by high among‐female the of storage organs, assuming paternity success improves when compatible organ. We use individual‐based simulations and an analytical model evaluate how on depends promiscuity level organ (hereafter, female preference variation). Simulations (10 mates female) showed stabilizing was low, disruptive high, consistent results. With low (2–3 female), all levels simulations, contrasting model. Promiscuity level, or mate sampling, thus has a strong impact resulting from preferences. Furthermore, male traits will occur under much more limited circumstances (i.e. only higher variation) than previous models suggest. Variation organs likely implications highly but does not explain differences less

Language: Английский

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Measuring Pre- and Post-Copulatory Sexual Selection and Their Interaction in Socially Monogamous Species with Extra-Pair Paternity

Cells, Journal Year: 2021, Volume and Issue: 10(3), P. 620 - 620

Published: March 11, 2021

When females copulate with multiple males, pre- and post-copulatory sexual selection may interact synergistically or in opposition. Studying this interaction wild populations is complex potentially biased, because copulation fertilization success are often inferred from offspring parentage rather than being directly measured. Here, I simulated 15 species of socially monogamous birds varying levels extra-pair paternity, where could independently cause a male secondary trait to improve success, sperm success. By the degree correlation between traits, show that several common statistical approaches, including univariate gradients paired t-tests comparing males within-pair they cuckolded, can give highly biased results for traits. These tests should therefore be avoided traits unless known uncorrelated trait(s) impacting In contrast, multivariate analysis regression proportion brood(s) sired on (including only broods ≥1 offspring) were unbiased, appear likely unbiased under broad range conditions mating system. addition, investigated whether occurrence pre-copulatory impacted strength selection, vice versa. found no evidence an simulated, Instead, direct each was independent other selection. Although independent, two positively correlated across both increased frequency copulations these species.

Language: Английский

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