... of Western Australia, professor Boomsma studied sperm competition in sister species of ants and bees ... and moths have two kinds of sperm in the 1970's." Similar sperm competition systems appear to have evolved ...
... term sperm competition can be used in two ways. In the broad sense, it involves a large range of morphological ... ’s the father). In the narrow sense, which is the focus of this article, sperm competition is used to denote the physiological processes occurring ...
... extreme cases involving sexual selection and sperm competition. However, by looking at data on a wide range of spiders, Wilder and Rypstra discovered that the size ...
... have hampered our progress in understanding the processes mediating sperm competition. It is commonly believed that selection for increased ... , one cannot attribute the evolution of longer sperm to any competitive advantage that length alone gives ...
... factor does indeed count. “The competition among sperms to fertilize a female’s eggs is an extremely ... a strong link between the degree of sperm competition and the size and speed of the sperms. Males with promiscuous females ...
... don't have Jenna Jameson?) so there's sperm competition but there are also other factors having to do with the internal workings of the female body (i.e. that magical place ...
... competes with that of other males in a process known as 'sperm competition'. Since males have finite resources to allocate ... mate with many males, so males are subject to sperm competition. However, the attractiveness of a male is determined ...
... can discriminate between their brethren and the competing sperm from other males, clustering with the closest relatives to swim faster in the race ... to be present only in some promiscuous species, where it affords an individual’s sperm a competitive advantage over that of other males.read ...
... goal with these flies was to tackle the mechanisms underlying sperm competition," says Pitnick. "Whenever a female mates ... in nature—there are conflicts between the sexes over paternity, as well as competition between rival ejaculates to fertilize eggs. Such postcopulatory ...
... quality under inbreeding is only detectable when sperm competition is invoked. "One limitation to this study is that the ancestral laboratory ... that female beetles use multiple mating to generate sperm competition and thereby avoid inbreeding depression ...
... actively choose more diverse MHC males or whether other factors like male-male competition or sperm competition play a role ...
... at the University of Sheffield. His research on promiscuity and sperm competition in birds helped to re-shape current understanding of bird mating systems. His ...
... . "But at least two hypotheses could account for this pattern – sperm competition on the one hand and male mating rate ... ejaculate and thereby provide males with an advantage in sperm competition (when males are vying for the fertilisation of the female ...
... from approaching females. "In the absence of male-to-male competition, we found that females will almost always choose a red ... , including male dominance, sneak behavior, and sperm competition." A forthcoming study will focus on how blue ...
... to ensure some degree of reproductive success by preventing sperm competition from subsequent males," says Grant, noting males tailor sperm expenditure according to how many competitors they face. Males are also more likely ...
