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Sperm speed cooperation

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A change in social status can quickly lead to a change in the quality of the seminal fluid produced by a male Chinook salmon as he responds to increased reproductive competition from higher-status males. Males compete fiercely with other males for access to reproductive partners Darwin, However, females often mate with multiple males, which means that the ejaculates of the males have to compete with each other in a process known as sperm competition Parker, Competition between males can also be modulated by social hierarchy: dominant males can monopolise access to females, reducing the risk of sperm competition, and making subordinate males much more likely to face sperm competition whenever they manage to mate. Theory predicts that males facing higher levels of sperm competition should preferentially invest in the production of competitive ejaculates, and there is substantial empirical support for this Parker and Pizzari,
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How fast do sperm swim and how do they find the egg?

Sperm speed cooperation
Sperm speed cooperation
Sperm speed cooperation
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How fast do sperm swim and how do they find the egg? | Questions | Naked Scientists

Log in Advanced Search. Sperm cells swim very efficiently when moving upstream against a current and may cooperate whilst doing so, scientists have observed. Researchers found that when sperm cells are faced with a current, they swim in a spiralling motion, rather than in a straight line, and move towards where the current is slowest. This causes the cells to accumulate in groups, swimming in shoals. This challenges the commonly held belief that sperm cells compete to reach the egg cell first.
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Sperm competition, cooperation

Journal of Plant Research. Sperm are ubiquitous and yet unique. Genes involved in sexual reproduction are more divergent than most genes expressed in non-reproductive tissues. It has been argued that sperm have been altered during evolution more than any somatic cell. Profound variations are found at the level of morphology, motility, search strategy for the egg, and the underlying signalling mechanisms.
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In the closing paragraph of on the origin of species Darwin famously said that nature was a war in which individuals struggle against each other and the environment for survival. However, while survival may be important from an individuals point of view, from an evolutionary perspective mere survival is not enough. Of course, survival is important too, but only when it leads to reproduction. In most species the reproductive success of females is limited by the rate at which they can produce offspring.
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