Happy birthday, Nick at Nite. This Nickelodeon primetime spin-off channel and home for classic sitcoms launched on July 1, 1985. Some of Nick’s current crop of retro programming didn’t even exist when it first started broadcasting and repackaged shows like “Mr. Ed” as campy nostalgia for baby boomer parents. Nick at Nite is now old enough to be recycled on Nick at Nite.

Nick currently broadcasts comedies from the 1980s and early 1990s, including “The Cosby Show,” “Fresh Prince of Bel Air,” “Murphy Brown” and “Roseanne.” In fact, by the time “Roseanne” appeared in 1988, Nick at Nite already had become part of the pop-cultural landscape, and characters on the show frequently quipped about old comedies they watched on Nick. This joke became very apt when Sarah Chalke debuted as the “new” Becky (replacing Lecy Goranson), echoing the Nick staple “Bewitched,” where Dick Sargent replaced Dick York as the hapless Darrin.

¢ Eight urbanites compete to see if they are worthy of saddles and spurs in the rodeo competition reality series “Cowboy U: Texas” (7 p.m., CMT).

¢ “Child Prodigies” (7 p.m., CBS) recalls news stories about gifted children, including a 14-year-old golf star and a 13-year-old musical whiz. Speaking of gifted youth, it looks like “Joan of Arcadia” is gone for good. The show will not return on next fall’s schedule, and CBS has moved repeats of “60 Minutes II” into its time slot effective next Friday.

Tonight’s other highlights

¢ Scheduled on “Dateline” (7 p.m., NBC): Tom Brokaw accompanies Aron Ralston to the remote Utah desert canyon where he was trapped under a boulder for six days before amputating his own leg with a pocket knife.

¢ The voices of Jeff Goldblum, Elizabeth Perkins and Tobey Maguire can be heard in the 2001 special-effects comedy “Cats & Dogs” (7 p.m., Fox).

¢ Sarah Michelle Gellar stars in the 2001 romantic thriller “Harvard Man,” (7 p.m., UPN).

¢ Coates’ past resurfaces on “JAG” (8 p.m., CBS).

¢ Double jeopardy on “Law & Order: Trial by Jury” (9 p.m., NBC).

Series notes

Tart art criticism on “8 Simple Rules” (7 p.m., ABC) … On back-to-back episodes of “What I Like About You” (7 p.m., WB), Vince’s surprise (7 p.m.), Luke Perry (7:30 p.m.).

On back-to-back episodes of “Hope & Faith” (ABC), matchmaking (7:30 p.m.), left at the altar (8 p.m.) … Rival birds to baste on “Reba” (8 p.m., WB).