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Current sperm competition determines sperm allocation in a Tephritid Fruit Fly
(Wiley Blackwell Publishing, Inc, 2015-05)
Sperm competition (SC) occurs when the sperm of two or more males compete for the same set of ova. Theoretical models and experimental observations indicate that the presence of rival males causes focal males to adjust ...
Female nutritional condition affects ovarian fluid quality in guppies
(The Royal Society, 2018-05-30)
Male and female gametes are often embedded in fluids that are produced by gonads and other reproductive tissues. Female reproductive fluids, usually called ovarian fluid (OF), which often constitute a relevant volumetric ...
Video imaging of the sperm acrosome reaction during in vitro fertilization
(Landes Bioscience, 2011-07)
Mammalian spermatozoa become competent for fusion with oocytes while traveling through the female reproductive tract and the oocyte´s extracellular investments. Recent studies highlighted the molecular mechanism of the ...
From sperm plug formation to ovulation: Morphological and ultrastructural modifications in the seminal receptacle of the blue crab Callinectes danae
(2021-03-01)
In species of Callinectes a sperm plug is formed in the seminal receptacle (SR) during the sperm transfer, which hinders the insemination by other males. In this study, we evaluated the morphology, histochemistry, and ...
An effective sperm competition avoidance strategy in crabs drives genetic monogamy despite evidence of polyandry
(Springer, 2016)
For polyandrous species where females have sperm storage structures, males develop several strategies to avoid sperm competition and thus to maximize the number of eggs fertilized. On the other hand, females may receive ...
Ejaculate allocation in Brachyura: What do males of Metacarcinus edwardsii respond to?
(2018)
In polygynous species, the sperm economy hypothesis predicts that males can adjust the amount of their ejaculate during copulation in response to (1) individual traits of females according to potential female fecundity, ...
Differential allocation in a gift‑giving spider: males adjust their reproductive investment in response to female condition
(BMC, 2021)
Background: When males are selective, they can either reject low-quality females or adjust their reproductive investment in response to traits that indicate female quality (e.g., body size or condition). According to the ...
Male dimorphism of a neotropical arachnid: harem size, sneaker opportunities, and gonadal investment
(OXFORD UNIV PRESS INCCARY, 2012)
Serracutisoma proximum is a harvestman with alternative male morphs. Large males use sexually dimorphic second legs in fights for the possession of territories on the vegetation, where females oviposit. Small males have ...
Male age and strain affect ejaculate quality in the Mexican fruit fly
(Wiley Blackwell Publishing, Inc, 2017-04)
Aging in all organisms is inevitable. Male age can have profound effects on mating success and female reproduction, yet relatively little is known on the effects of male age on different components of the ejaculate. ...
Integrative depiction of the male reproductive system of the commercial purple crab Homalaspis plana (Platyxanthidae): Structure and function
(2019-01-01)
The information available on structures and function of reproductive systems are female-biased in many animal groups and crabs are not an exception. However, knowledge about the male reproductive system can help us to ...