LivingIn sperm, size is not important
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In sperm, size is not important

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espermaThe length of the tail of thespermatozoonit does not always determine how fast you can move. This is indicated by a new research, published in the journalBMC Evolutionary Biology, which shows that in the counterintuitive microscopic world in which sperm move,streamlined design and large sizes are not always synonymous with speed.

The researchers, led by Stuart Humphries of the University of Sheffield, have studied the link between the shape of sperm and the speed at which they move. And they have concluded thatthe length of the head and tail or their set does not provide any advantage to the sperm in their race to the ovule. In fact, according to Humphries, the evolution of longer sperm cannot be attributed to any competitive advantage. On a microscopic scale, although a longer tail allows the sperm to generate more momentum, the resistance created by the sperm head is often sufficient to counteract any increase in speed. “Actually, the goal of evolution is the relative lengths of the sperm parts versus their total length,” says the researcher.

“Regardless of whether the length of the tail, the head or the total is taken into account,any attempt to associate a single measure of length with velocity is probably futile“Humphries adds. Instead, consider theBalancebetween the resistance of the head and the impulse of the tail of the sperm. With the conclusions of this work they couldimprove male sterility treatments, as well as fertilizationin vitro.

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