Nature is red in tooth and claw in both these natural history documentaries, in which a variety of beasts take their positions in their respective food chains and not a human being in sight. Disney's African Cats takes an anthropomorphic look at two prides of lions, one headed by Fang, the other by Kali, living on either side of an unnamed African river (actually in the Masai Mara nature reserve in Kenya), and a cheetah called Sita and her brood. There are some marvellous images, most memorably perhaps a herd of wildebeest shot from high in the air as they cross a ford and fan out over the plain. But it's Kiplingesque nursery ethology, and one distrusts the editing.

Dinotasia features CGI dinosaurs preying on one another in various genuine locations from Jurassic times to the ice age, with each chapter ending on a bleak note. Patrick Stewart delivers an avuncular commentary for African Cats, and I'm sure it's far superior to the one used in the American version. Dinotasia is narrated by Werner Herzog with his customary shock and awe.