DOMESTIC goddess Nigella Lawson is the subject of Who Do You Think You Are? ( Sunday, 7.30pm, SBS) as she traces her mother’s side of her family, the Salmons, to Ashkenazi Jewish ancestors in The Netherlands and the Rhineland of Germany. Lawson’s glamorous mother was a catering dynasty heiress and her politician father was Maggie Thatcher’s golden boy in the 1980s. More than six million British viewers watched this quite revealing and intimate episode featuring the cook who takes the cake. Far less voluptuous, the Mythbusters team up in Mythbuster Christmas Special ( Monday, 7.30pm, SBS) to dismantle holiday treats in their wonderfully vaudeville version of science. Will putting a silver spoon in a champagne bottle keep the bubbly fizzy? Does a snowman melt faster with its clothes on or off? And can a falling icicle kill you? What would our zanies make of Dragons Alive: Smart Reptiles ( Tuesday, 8.30pm, ABC), which reveals that alligators, chameleons, snakes, iguanas and turtles are the biotechnology wizards of the animal world? With a superhero’s skills they fly, hang upside down, spit poison, use X- ray vision and walk on water. Which they do with more facility than sharks can reproduce, as revealed in Shark Sex ( Wednesday, 8.30pm, SBS), which unveils breathtaking images of the deadly risks grey sharks take in mating around the atoll of Rangiroa in the heart of the Pacific.