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spermcompetition, etc ; Cyprinus carpio; Salmonidae; aquaculture; calcium; carp; chemotaxis; evolution; males; spermatozoa; Show all 10 Subjects
Abstract:
... During evolution, the fish adopted versatile spawning tactics, which allowed them to use sperm competition effectively and prevent fertilization by inappropriate male gametes. Ovarian fluid (OF) affects spermatozoa performance in several fish species, as shown mainly in salmonids, and likely contributes to their reproductive tactics. Common carps utilize different spawning behavior compared to sal ...
spermcompetition, etc ; Callosobruchus maculatus; copulation; females; males; phenotype; sexual selection; spermatophores; temperature; Show all 9 Subjects
Abstract:
... Sexual selection theory has proven to be fundamental to our understanding of the male-female (sperm-egg) interactions that characterise fertilisation. However, sexual selection does not operate in a void and abiotic environmental factors have been shown to modulate the outcome of pre-copularory sexual interactions. Environmental modulation of post-copulatory interactions are particularly likely be ...
spermcompetition, etc ; Platyhelminthes; evolution; hermaphroditism; interspecific variation; intraspecific variation; plasticity; selfing; sex allocation; spermatozoa; Show all 10 Subjects
Abstract:
... Sex allocation theory in simultaneous hermaphrodites predicts that optimal sex allocation is influenced by local sperm competition, which occurs when related sperm compete to fertilize a given set of eggs. Different factors, including the mating strategy and the ability to self‐fertilize, are predicted to affect local sperm competition and hence the optimal SA. Moreover, since the local sperm comp ...
spermcompetition, etc ; Neotropics; Rhodnius prolixus; entomology; females; hematophagous insects; males; reproductive behavior; risk; stereotyped behavior; Show all 10 Subjects
Abstract:
... Social context is a key factor affecting sexual behaviour and cannot be neglected in gregarious species, such as triatomine blood-sucking bugs. Here we study the influence of the social context on the sexual reproductive behaviour of males and females of Rhodnius prolixus Stål. Specifically, we identify and compare the frequencies and sequence of sexual behaviours exhibited by a focal pair in pres ...
spermcompetition, etc ; copulation; ecology; females; genotyping; males; paternity; polyandry; progeny; selection intensity; sexual selection; spermatozoa; spiders; Show all 13 Subjects
Abstract:
... Sperm competition drives traits that enhance fertilization success. The amount of sperm transferred relative to competitors is key for attaining paternity. Female reproductive morphology and male mating order may also influence fertilization, however the outcome for sperm precedence under intense sperm competition remains poorly understood. In the polyandrous spider Pisaura mirabilis, males offer ...
spermcompetition, etc ; Charybdis hellerii; arthropods; crabs; dehiscence; electron microscopy; females; gonadosomatic index; invasive species; males; seawater; spermatophores; spermatozoa; Show all 13 Subjects
Abstract:
... The male reproductive system in Portunoidea is voluminous in order to produce the sperm plug, avoiding sperm competition. The portunid crab, Charybdis hellerii, is a successful invasive species, and this study describes the male reproductive system under light and electron microscopy and evaluates the gonadosomatic index and spermatophore dehiscence compared to other species that produce a sperm p ...
spermcompetition, etc ; Pseudomys; cryptic species; epididymis; intraspecific variation; lipids; mammalogy; mice; monogamy; polyandry; spermatozoa; tail; Northern Territory; Queensland; Western Australia; Show all 15 Subjects
Abstract:
... The delicate mouse (Pseudomys delicatulus) ranges from Queensland to northern Western Australia. In this study the morphology of the cellular organisation of the testis and cauda epididymal spermatozoa are compared. Individuals from the mainland of the Northern Territory and Western Australia invariably have only 60–70% of the testes composed of seminiferous tubules with the interstitial tissue be ...
spermcompetition, etc ; Gryllidae; entomology; genetic variation; microsatellite repeats; transcriptome; Show all 6 Subjects
Abstract:
... Microsatellite markers have been used extensively in studies of sperm competition and the genetic diversity of organisms. In the present study, we performed transcriptome sequencing for Velarifictorus aspersus and developed simple sequence repeat markers to identify valuable markers for genetic studies. The average total length of the V. aspersus transcriptome sequence was 7.70 Gb and it contained ...
spermcompetition, etc ; animal behavior; animals; courtship; ownership; reproductive success; Show all 6 Subjects
Abstract:
... Whenever resources are limited and indivisible, fighting will evolve as a means to resolve ownership. Among such resources are mates, and individuals (usually males) of many species compete agonistically with rivals in order to gain access to potential mates. However, securing access is not necessarily enough to guarantee a mating or, if a mating is obtained, to guarantee that it is effective for ...
spermcompetition, etc ; acrosome reaction; cattle; females; follicular fluid; sperm capacitation; spermatozoa; swine; trypsin; viability; Show all 10 Subjects
Abstract:
... While follicular fluid (FF) is known to enhance the functional properties of spermatozoa, the role of FF-derived extracellular vesicles (EVs) in this respect is unknown. We hypothesized that bovine FF EVs convey signals to spermatozoa supporting sperm viability, inducing sperm capacitation and acrosome reaction. In this study, the effects of bovine FF EVs on sperm functions are evaluated. Irrespec ...
spermcompetition, etc ; corals; evolutionarily stable strategy; females; hermaphroditism; males; models; risk; sex allocation; sociobiology; Show all 10 Subjects
Abstract:
... In most sex-changing fishes in coral reefs, a dominant male and multiple females form a mating group (harem). In a few species, the subordinates are simultaneous hermaphrodites that may act as sneakers. In this paper, we ask whether the subordinates in most sex changers choose to be female or whether they are forced to give up their male function to avoid eviction by the harem holder. We consider ...
spermcompetition, etc ; DNA; chromosome segregation; ecology; eukaryotic cells; kinetochores; mammals; meiotic drive; microtubules; oocytes; phylogeny; Show all 11 Subjects
Abstract:
... Centromeres have central functions in chromosome segregation, but centromeric DNA and centromere‐binding proteins evolve rapidly in most eukaryotes. The selective pressure(s) underlying the fast evolution of centromere‐binding proteins are presently unknown. An attractive possibility is that selfish centromeres promote their preferential inclusion in the oocyte and centromeric proteins evolve to s ...
... Subsocial Cryptocercus cockroaches are the sister group to termites and considered to be socially monogamous. Because genetic monogamy is a suggested requirement for evolution of cooperative breeding/eusociality, particularly in hymenopterans, clarification of the mating biology of Cryptocercus would help illuminate evolutionary trends in eusocial insects. To investigate possible extra‐pair patern ...
spermcompetition, etc ; Bos javanicus; Bubalus depressicornis; cattle; cryopreservation; endangered species; loss of heterozygosity; monogamy; polygyny; spermatozoa; whole milk; Show all 11 Subjects
Abstract:
... Storing cryopreserved spermatozoa in a genome resource bank safeguards against the loss of heterozygosity in endangered species and provides opportunities to reincorporate genes into populations through the application of assisted reproductive technologies. The aim of this study was to demonstrate the effect of breeding strategy on ejaculate characteristics to illustrate how this information may b ...
... In species with internal fertilization, copulation is characterized by the mechanical interaction of male and female genitalia. Genital interaction during copulation stimulates the neuroendocrine system, promoting the physiological changes necessary for the initiation of pregnancy. Previous studies on mice have shown that the baculum (penis bone) influences male reproductive success under a compet ...
spermcompetition, etc ; Scaptotrigona; evolution; genetic variance; heritability; males; monogamy; phenotype; social insects; spermatozoa; stingless bees; storage time; viability; Show all 13 Subjects
Abstract:
... The influence of long-term storage on the evolution of social insect male ejaculates remains a puzzle. Here, we studied the influence of sperm storage on male ejaculates in the stingless bee Scaptotrigona aff. depilis, a species where queens mate with a single male and thus do not trigger sperm competition. We estimated quantitative genetic parameters by sampling males from six colonies and two co ...
... Theoretic and empirical studies show that social surroundings experienced by male insects during their larval or adult stage can influence their testicular investment in diverse ways. Although insect pupae do not feed and crawl, they can communicate using sex-specific and/or non-sex specific cues. Yet, it is unknown, in any insect, whether and how male pupae can fine-tune their resource allocation ...
spermcompetition, etc ; biodiversity; demography; extinction; genes; invasive species; mice; pest control; polyandry; probability; simulation models; stochastic processes; vertebrate pests; Show all 13 Subjects
Abstract:
... Invasive alien species continue to threaten global biodiversity. CRISPR‐based gene drives, which can theoretically spread through populations despite imparting a fitness cost, could be used to suppress or eradicate pest populations. We develop an individual‐based, spatially explicit, stochastic model to simulate the ability of CRISPR‐based homing and X chromosome shredding drives to eradicate popu ...
spermcompetition, etc ; females; males; sexual selection; spermatozoa; Show all 5 Subjects
Abstract:
... Ageing and sexual selection are intimately linked. There is by now compelling evidence from studies performed across diverse organisms that males allocating resources to mating competition incur substantial physiological costs, ultimately increasing ageing. However, although insightful, we argue here that to date these studies cover only part of the relationship linking sexual selection and ageing ...
spermcompetition, etc ; Gryllus bimaculatus; animal behavior; antioxidants; experimental design; males; oxidative stress; progeny; reproductive success; risk; sexual selection; spermatozoa; viability; Show all 13 Subjects
Abstract:
... Sperm competition theory predicts that males should strategically adjust the allocation of sperm in response to the level of sperm competition (i.e. the number of competing ejaculates). Predictions of sperm competition models have mostly focused on sperm numbers. However, whether males strategically adjust other important traits of their ejaculate such as sperm antioxidants in response to potentia ...