- News Home
6 March 2014 1:04 pm ,
Vol. 343 ,
Antiretroviral drugs can protect people from becoming infected by HIV. But so-called pre-exposure prophylaxis, or PrEP...
Two studies show that eating a diet low in protein and high in carbohydrates is linked to a longer, healthier life, and...
Considered an icon of conservation science, researchers at World Wildlife Fund (WWF) headquarters in Washington, D.C.,...
The new atlas, which shows the distribution of important trace metals and other substances, is the first product of...
Early in April, the first of a fleet of environmental monitoring satellites will lift off from Europe's spaceport in...
Since 2000, U.S. government health research agencies have spent almost $1 billion on an effort to churn out thousands...
Magdalena Koziol, a former postdoc at Yale University, was the victim of scientific sabotage. Now, she is suing the...
- 6 March 2014 1:04 pm , Vol. 343 , #6175
- About Us
ScienceShot: Why Sperm Swim in Circles
11 May 2010 7:01 pm
Perhaps it's no surprise that sperm often swim in circles. They must rely on a tail smaller than the width of a human hair to conquer an obstacle course with 200-million-to-one odds. Until now, scientists blamed sperms' circular locomotion on their erratic, asymmetric tail propulsion. But where they swim might be more important than how they swim, according to a study published online tomorrow in the Journal of the Royal Society Interface. Researchers simulated sperm cell migration and found that if the surrounding fluids (such as semen or vaginal secretions) are viscous enough, the sperm tails will buckle in the current, trapping the cells into a circular loop they can't escape even if the cells swim perfectly. Knowing how to trap sperm in the right places could improve the effectiveness of in vitro fertilization and other reproductive technologies, experts say.
See more ScienceShots.