Wow! Another theory disproven. Turns out, sperm don’t actually swim. Instead, “The sperm body spins at the same time that the tail rotates around the swimming direction. Sperm ‘drills’ into the fluid like a spinning top by rotating around itself whilst its tilted axis rotates around the centre.

“This is known in physics as precession, much like the precession of the equinoxes in our planet.”

Who knew? Drillers, otters, but not swimmers!

https://theprint.in/health/sperms-dont-swim-scientists-have-been-wrong-for-the-last-350-years/477006/