The team over at ASAPScience are looking at the top of heads today, giving a very quick explanation of why people say that if you wonder whether you're going to go bald or not, to "look at your mother's father".
While grandpa may be to blame for much of it, there's some new science that suggests possible other factors in baldness - so it's not always his fault.
In my case, my mother's father died at an early age, so I'll never really know. So far, though, all of the hair on my head is still there (although I do keep it short).
Keith Shaw rounds up the best in geek video in his ITworld.tv blog. Follow Keith on Twitter at @shawkeith. For the latest IT news, analysis and how-tos, follow ITworld on Twitter, Facebook, and Google+.