Like birds of a feather, sperm flock together

Fluid dynamics of medium leads to collective swimming

flock of birds

GROUP DYNAMICS  Like birds, sperm also move in groups. But physicists have found that, compared with flocking animals, sperm’s collective behavior can be explained by the physical properties of the fluid the sperm travel through. 

USFWS Mountain-Prairie/Flickr (CC BY 2.0)

BALTIMORE — When it comes to swimming sperm, it’s not every man for himself.