The following is taken from the article:
"Those who believe in the Yeti, Bigfoot and the Loch Ness Monster* need basic instruction in sex," said Stuart Pimm, an ecologist at Duke University, in an email. "Each Yeti has two parents, four grandparents and so on," he said. "There should have been herds of (Yetis)," he wrote. "Where were they hiding?"
In my opinion this statement is wrong because sex and reproduction are different things, for example the Primates known as Bonobo (Pan paniscus) engage in "sex" that has nothing to do with reproduction.
I also wonder why the word "herds" was used? Troop is the word generally used to describe a group of Primates like Gorillas, Chimps or Orangutans.