Mark McClusky says for elite athletes today, pushing boundaries and breaking records is all about "the aggregation of marginal gains."
The business of making babies has been in the news a lot recently. A 33 year-old lawyer from Boston discovered he has spawned more than 70 kids after donating to a sperm bank during his three years of law school.
Some of his offspring tracked him down through a website that allows children to find their biological parents. Some of those children have voiced concern that they could unknowingly have relations with their brother or sister. So how does the reproductive industry work? Who monitors it? And is anyone keeping track?