Chris Daugherty beat two tribes of reality-TV backstabbers on Survivor: Vanuatu, but he couldn’t beat the fictional backstabbing suburbanites of Wisteria Lane. According to Nielsen, Sunday’s Survivor finale was the least-watched of all nine editions to date. CBS was still the most-watched network over the course of the evening, and the network did take a bite out of ABC’s Sunday hit Desperate Housewives, whose audience was down 5 million from its season high of 27 million two weeks ago. Still, Housewives stole some of CBS’ thunder, drawing 22.2 million viewers during the 9 p.m. hour, opposite the second hour of the Survivor finale, which drew 20.3 million. (The first hour drew 18.9 million.) Obviously, the Vanuatu vixens should have staged a gown-shredding catfight.