The Darwin Awards are a tongue-in-cheek honor, originating in Usenet newsgroup discussions around 1985. They recognize individuals who have supposedly contributed to human evolution by selecting themselves out of the gene pool via death or sterilization by their own actions.
The project became more formalized with the creation of a website in 1993 and followed up by a series of books starting in 2000, authored by Wendy Northcutt. The criterion for the awards states, "In the spirit of Charles Darwin, the Darwin Awards commemorate individuals who protect our gene pool by making the ultimate sacrifice of their own lives. Darwin Award winners eliminate themselves in an extraordinarily idiotic manner, thereby improving our species' chances of long-term survival."
Accidental self-sterilization also qualifies; however, the site notes: "Of necessity, the award is usually bestowed posthumously." The candidate is disqualified, though, if "innocent bystanders", who might have contributed positively to the gene pool, are killed in the process.
The Darwin Awards books state that an attempt is made to disallow known urban legends from the awards, but some older "winners" have been "grandfathered" to keep their awards. The Darwin Awards site does try to verify all submitted stories, but many similar sites, and the vast number of circulating "Darwin awards" emails, are largely fictional.