Summer Olympics: NBC (Ch. 5) has coverage from 10 a.m.-1 p.m., 7 p.m.-midnight and 12:35-1:30 a.m.; CNBC from 3-6 p.m. and 10 p.m.-3 a.m.; MSNBC from 7 a.m.-3 p.m. and 3-7 a.m.; Oxygen from 7-9 p.m.; and USA from 7-10 a.m. and midnight-7 a.m.

Greatest American Dog (7 p.m., Ch. 2): The dogs compete in a painting competition. Really.

Nova scienceNOW (8 p.m., Ch. 7): Reports on genetic research and ancient papyrus scrolls.

Terminator: The Sarah Connor Chronicles (8 p.m., Ch. 13): John learns the future is more unsafe than he had hoped. (R)

Mythbusters (10 p.m., Discovery): The team tests viral videos.

Man vs. Wild (11 p.m., Discovery): Bear Grylls takes on the swamps of the Deep South.