Study shows vampire bats feed group mates to ensure others will feed them later
Size matters when it comes to sperm dominance
A tiny fruit fly has the bizarre distinction of possessing the longest sperm of any animal—20 times the length of its own body and 1,000 times that of human sperm.
Short winter days trigger aggression hormones differently based on sex
Indiana University researchers have discovered a hormonal mechanism in hamsters that connects short winter days with increased aggression in females, and that it differs from the mechanism that controls this same response ...
The biggest sperm come in the smallest packages—and other surprising facts about male sex cells
Most people probably think of sperm as the microscopic tadpole-like things wriggling around in human semen. But there is an astonishing amount of diversity in the size, shape and number of sperm produced by male animals. ...