Throwing the gag out with the bathwater

According to Aristotle, it takes a newborn infant about 40 days to learn to laugh. What would the ancient Greek make of Holding the Baby (ITV, Fri)? The eponymous child in the show shares a script with three adult characters who couldn't crack a joke with a wrecking ball. He'll clearly be needing a good deal more than the Aristotelian allowance of 40 days to learn the basic rudiments of creasing up.

Howard Jacobson cited Aristotle's 40-day dictum in Seriously Funny (C4, Tues). This series of illustrated lectures has chosen to override the wisdom of centuries that says you can't analyse comedy. You probably can't, but you can analyse Holding the Baby, because it isn't comedy. It's easy to tell that it's an impostor masquerading as a sitcom: it comes with the ITV logo, a guarantee of fake comic merchandise. It would be unfair to heap all the blame for its mirthlessness on Nick Hancock, the infant's screen father, but he's disastrously miscast, and seriously unfunny. Hancock has made the classic - you could even say classical - error of believing all his press, and thinking he can do no wrong. In academic circles they sometimes call it hubris. He plays against type as a domesticated single parent who's had the testosterone surgically drained out of him. In last night's third episode, someone described him as "one of the girls". Prunella Scales as Derek Jacobi's mother in Breaking the Code (BBC1, Wed)? Fair enough. Robson Green beds Francesca Annis in Reckless (ITV, Thurs)? Perhaps. Freddie Starr as ruthless drug baron in Supply and Demand (ITV, Wed)? Why not? But Nick Hancock does nice? It puts your disbelief, already suspended from a great height by the sitcom's triangular menage, under impossible strain.

There was newborn life all over the screen this week, most of it in the form of identical twins. Identical twins were the perennially creepy subject of Cutting Edge (C4, Mon), which sought out split-egg siblings in all their glorious variety: the twins who wouldn't be parted when one of them got hitched; the twins who married twins; the twins separated at birth and adopted; the twin who had suffered the strange semi-death of a sibling's demise. The most scientifically interesting pair of twins consisted of two women from the same egg who had gone down separate sexual roads, one straight, the other not: proof, if ever it were needed, that sexuality is not genetically predetermined.

The commonplace among these twins was that, in childhood, the mirror held no curiosity for them, as they spent their every waking moment with a mirror-image before them. You even saw one pair of twins applying each other's make-up, as if through the looking-glass. Most of us, though, are enthralled by what we see in the mirror, even if it's starring in a wildlife documentary. A pair of twin lemurs took the juvenile lead in a particularly anthropomorphous episode of Natural World (BBC2, Sun). Anthropomorphism means holding a mirror up to nature and seeing only yourself. Whenever a young lemur was separated from its mother, you could practically see the bubble caption reading "I want my mummy".

There's a high accidental mortality rate among infant lemurs, caused almost entirely by apprentice tree-climbers falling fatally out of high branches. You sort of wish one of the two shows hosted by Bob Mills would take a leaf out of their book. Scientists are at a loss to explain how it happened, but a fertilised egg split in the ideas conference and turned into twin entertainments, both fronted by Mills, both running on the same night. Between the Show (C4, Sat) and In Bed with MeDinner (ITV, Sat), the former looks a much riskier venture, because it's trying to look like the factual twin of The Larry Sanders Show. It may yet fall out of the trees, but scores a lot of points for bravery.

And, of course, Ruby Wax Meets ... (BBC1, Mon) gave birth to a second interview with Pamela Anderson. This was weirdly similar to its older sibling, with lots more of those jokes about positions and breasts that nine million of you enjoyed so much last time round. You were reminded of that woman who, via surrogate wombs, recently became the mother of twins born three years apart. The only difference from Wax's encounter with Anderson last year was that this time both women brought sprogs along. This second series of celebrity ambushes is falling a lot flatter than Anderson's twin peaks, doubly inflated by a Californian compound of silicone and milk.