This cracked me up!

The cringeworthy "dad dancing" witnessed at wedding receptions every weekend may be an unconscious way in which ageing males repel the attention of young women, leaving the field clear for men at their sexual peak.

"The message their dancing sends out is 'stay away, I'm not fertile'," said Dr Peter Dad, a psychologist at the University of Hertfordshire who has compared the dancing styles and confidence levels of nearly 14,000 people.

http://www.telegraph.co.uk/science/scien...ists-claim.html

Why just dad? The above perfectly fits my mum, too.

Actually, I've seen plenty of young people who are bad dancers as well. Eugenics is alive and well! Avoid bad dancers!