Part of the show Science of Left Handedness - Chris McManus
John and Abby, email asked:
How fast do sperm swim?
About 3 mm per minute. Interestingly, scientists have found that mouse sperm are very altruistic and line up nose-to tail to swim along in convoy, thus helping more of them make it further. In humans, results announced by Brazilian scientists at a meeting of the American Society for Reproductive Medicine meeting in San Antonio, reveal that sperm motility can be increased by caffeine. Dr Fabio F. Pasqualotto, a human reproductive medicine specialist at the Conception Center for Human Reproduction, University of Sao Paulo, Brazil, compared semen samples from 232 non-coffee-drinkers, 156 men who drank 1 to 3 cups daily, 198 men who drank 4 to 6 cups daily and 164 heavy drinkers who consumed more than 6 cups per day. He found no differences in the quality of the sperm in all cases but did observe that the sperm from the coffee drinkers appeared to be in more of a hurry, suggesting that a cup of coffee could boost fertility! Meanwhile, another way to speed up sperm is to send it into space. German researcher U. Engelmann measured sperm swimming speeds aboard a European Space Agency mission in 1988 and found that the cells moved faster under microgravity conditions.