Soon he decided to look at his ejaculate – probably not by accident – and found tiny, swaying creatures with tails, which he dubbed “animals”.
As scientists have continued to look down on their microscopes for centuries, there is no doubt that their eyes saw and recorded on film: Sperm floats, moving its tails to the side.
Why shouldn’t we trust our eyes? So science has believed in it ever since.
It turns out that our eyes were wrong.
“If you want to see a real beating of the tail, you need to move the sperm and turn the sperm. So it’s almost like you need to make (the camera) really tiny and stick it to the head of the sperm,” said Gadela.
Gadelli’s co-authors, Gabriel Corkidi and Alberto Darson of the National Autonomous University of Mexico, created the method. Using state-of-the-art instruments, including a high-speed camera that can record more than 55,000 frames per second, the researchers were able to see that sideways movement is actually an optical illusion.
In fact, the tail of the sperm blows on one side only.
This unilateral blow should cause sperm to float in an eternal circle, Gadella said. But no, semen was smarter than that.
“Human sperm have found out if they are rolling while swimming, like playful otters pushing through water. Their one-way course will be average and they will swim forward,” said Gadela, an expert in fertility mathematics.
“The rotation of sperm is something very important. It is what allows the sperm to regain symmetry and really be able to go straight,” he said.
The results came as a real surprise, Gadella said, so the team spent nearly two years repeating the experiment and cross-checking the math. Results: like the Earth turned out not to be flat, the semen doesn’t really swim like snakes or pimples.
So why does it matter?
“Perhaps the rolling movement hides some subtle aspects about the health of this sperm or how well it can travel quickly,” Gadela said.
“These are all very hypothetical questions. We hope that more scientists and fertility experts will be interested and ask, ‘Okay, how does this affect infertility?’ “
As for how you feel like overturning more than 300 years of scientific assumptions, Gadella is modest.
“Oh my God, I always have a deep feeling that I’m always wrong,” he said.
“Who knows what we’ll find next? It’s a measurement that gives a tool that has its limitations. We’re right now, but we may be wrong again when science advances. And hopefully it will be something very exciting that we will to study in the next few years. “