Dark-field microscopy of individual sperm at 200 frames per second in media with varying shear rates (Scale bar is 20 micron) Sperm can modulate their energetics by regulating their flagellar waveform ...

Every time a man ejaculates about 55m sperm are released. This is equivalent to more than six times the entire population of London or New York, and more than twice the population of Shanghai city.

Karen Hopkin: This is Scientific American’s Science, Quickly. I’m Karen Hopkin. Swimming against a current can be tough. But imagine having to do it in a fluid with the consistency of corn syrup. That ...

Sperm can modulate their energetics by regulating their flagellar waveform -- how the sperm oscillate their tails -- in order to adapt to varying fluid environments, potentially optimizing their ...