(Photo: Peter Mooney)
Previous studies indicate that men who have ring fingers that are longer than their index fingers tend to have higher sex drives and sperm counts. They have greater "reproductive potential." A new study finds that long distance runners--specifically marathon runners--tend to have longer ring fingers. The authors take this as evidence that runners have an advantage in mating.
The study measured 542 men at the Robin Hood Marathon in Nottingham, UK. The Daily Telegraph reports on the results:
They found that the 10 per cent of men with the most masculine digit ratios were, on average, 24 minutes and 33 seconds faster than the 10 per cent of men with the least masculine digit ratios, suggesting that those who were better runners also had increased fertility.
“The observation that endurance running ability is connected to reproductive potential in men suggests that women in our hunter-gatherer past were able to observe running as a signal for a good breeding partner,” said the study’s lead author Dr Danny Longman.
“It was thought that a better hunter would have got more meat, and had a healthier – and larger – family as a consequence of providing more meat for his family.
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This arrangement is taken to extremes in dolphins and whales (which have no external scrotum), which run blood vessels through their fins to cool it, and then direct the cooled blood to their (internal) testes.
http://www.nytimes.com/2002/01/29/science/how-dolphins-keep-their-cool-in-the-zone-that-counts.html