Primetime Ratings: Dogs, Dancers and Doctors

CBS' Greatest American Dog bites Fox's Are You Smarter than a Fifth Grader .

If the ratings for CBS' Greatest American Dog, which premiered Thursday night, are any indication, American viewers like dogs a little more than they like fifth-graders.

The CBS reality show that pits dogs and their owners in a competition for most trainable team edged out Fox's Are You Smarter than a Fifth Grader at 8 p.m. in the 18-49 demographic (2.1 rating to 2.0) and easily prevailed in total viewers (9.4 million to 7 million).

NBC was third in the 8 p.m. time slot with a rerun of Last Comic Standing (1.2 demo rating, 3.4 million total viewers). The network programmed three hours of the stand-up-comedian competition show Thursday.

At 9 p.m. Fox's So You Think You Can Dance easily beat a rerun of CBS' CSI in the demo (3 rating to 2) but CSI raked in more total viewers (9.7 million to 8.7 million).

At 10 p.m., NBC won the hour in the demo, posting a 2.2 rating with a new installment of Last Comic Standing. And ABC News documentary series Hopkins gave the network its only bright spot on an utterly anemic night of Ugly Betty and Grey's Anatomy reruns, winning the 10 p.m. hour in total viewers with 5.47 million.