Before you lay out thousands of rands on sporting equipment for your budding Benni McCarthy, measure his fingers. Scientists have found that the longer a child's ring finger compared with his index finger, the more testosterone he has.This is linked to a capacity for greater sporting endurance.Dr Joe Barker, of York University, Canada, said that although the comparison should not be used to make talent identification decisions, it would help to differentiate athletes from non-athletes.Speaking at the Youth ID and Development Conference, at the Sports Science Institute in Newlands yesterday, Barker said birth date and dexterity were interesting indicators."If you look for sporting talent in kids at, say, age seven, you normally group them into the same birth year, when the actual difference in age between them could be up to 12 months. That's over 15% of their life experience."So things like speed, power and size aren't necessarily talent. It's just older kids who are being selected."But, he admitted: "We don't know that if you're a good performer at 10 that you'll be good at 20."The [statistical] evidence says probably not."Barker said overbearing parents who over-emphasised competition and winning were a recipe for burnout and high anxiety in children...