For Horizon's fascinating investigation into the ancestral relationship between man and dog, a record-breaking number of illustrious boffins had been compressed into 60 minutes of television. We met Dr Anna Kukekova from Cornell University, who has been conducting research into which gene makes silver foxes (dogs by any other name) either tame or wild.

Perception was everything last night in Garfield Kennedy’s fascinating if, at times, frustrating documentary, The Trials of Amanda Knox. Was the American student who was convicted last month of murdering her British flatmate in Perugia, Meredith Kercher, a scheming hussy into (very) extreme sex games, or just an averagely adventurous twentysomething turned into a scapegoat by an Italian judiciary that had already convinced itself of her guilt? Kennedy’s film considered the evidence, and it also detailed the concomitant trial by the media - and there, to a degree, is a problem. Because this documentary is also “the media”, and Knox’s case (appeal pending) is not closed. Somewhat misleadingly, it could be argued, the film was screening in More4’s True Stories slot. But was this only the partial truth, with some added special pleading?

Television doesn’t do eroticism at all well. Perhaps, rather like a truly horrifying horror film being unwatchable, a properly erotic drama would never pass TV’s internal censors. Dennis Potter tried it with his 1989 love letter to Gina Bellman, Blackeyes, but ended up dubbed “Dirty Den” for his troubles. And what is erotic anyway – just a glimpse of stocking, or the full-on and (for me, anyway) embarrassing sight of Billie Piper in fishnets and suspender belt? It's a question of taste, I guess.

Saving the planet from ecological disaster is all very laudable, but be careful what you wish for. In this two-part Anglo-Canadian production of John Wyndham's 1951 sci-fi novel, the voracious man-eating plants called triffids had been artificially cultivated as a fuel source, so successfully that triffid oil had enabled the world to wean itself off fossil fuels and thus curtail global warming. The story didn’t bother itself with those pesky climate change deniers.

There was something very postmodern about the resumption of Quentin Crisp’s story. To recap, in case you missed episode one back in 1975, The Naked Civil Servant has been turned into a successful television drama, and its subject into a celebrity.

The end of the South Bank Show? Surely some mistake. But there was Melvyn, looking into the camera with a resigned air, telling us that this film about the Royal Shakespeare Company (“possibly the greatest theatre company in the world”) was indeed the end of the line, give or take the occasional retrospective special.

Time was when British families planned Christmas Day around The Queen in the afternoon and (depending which generation you fall into) Morecambe and Wise, Victoria Wood, French and Saunders or The Vicar of Dibley in the evening. But now it seems television bosses have all but given up on offering family entertainment, as BBC One's comedy fare was transmitted entirely after the watershed and ITV1’s sole offering, Ant & Dec’s Christmas Show, was broadcast on Boxing Day.

The BBC's reinvention of Doctor Who under the auspices of Russell T Davies has proved to be an inspired upgrade of a legendary 1960s marque fit to rank alongside BMW's resuscitation of the Mini, though it would hardly be sensible to argue that the new-look Doctor is distinguished by Germanic precision engineering or a coolly mathematical design philosophy. Quite the opposite.

There were some odd sights in Christmas Day viewing but none more discomfiting, I’d bet, than seeing a ballerina lying on a physio’s couch having a leg dragged quickly up to touch the side of her head while the other leg lay perfectly still pointing downwards. Can the body really do that? Another weird sight - dozens of people in full 18th-century French costume and wigs dancing in 40-degree heat on a Cuban stage. Meanwhile coachloads of dancers were going down with swine flu and a 45-year-old retired dancer was flown in from Germany to take the part of a 20-year-old.