TELEVISION / What's it all about, aphid?

ON Channel 4 last night - and, it must be said, well within the stipulated adult viewing period - Hannah Gordon stood up for orgasm. 'For sheer concentration of pleasure,' she explained, 'very little will match it.' This observation came at the end of an hour in which The Sexual Imperative (with Gordon on voiceover) had pushed and prodded at the question of sexual attraction. And it seemed a perfectly reasonable conclusion for the programme to come to, though perhaps most people could have arrived at it without activating six researchers, 17 scientific consultants and no fewer than seven separate sources of film archive material, all named in the credits at the end.

We had opened with a woman walking through London in a small dress, while men swivelled and went cartoon-eyed. Evidently, this sequence was intended to indicate how sex preoccupies us. It also offered up a picture of sexual politics not seen since The Dick Emery Show. Still, these were the last humans we'd be looking at for a long time, because the programme then sped off round the world, seeking enlightening parallels in the animal kingdom, starting with a small clearing in the jungle, where pygmy chimps were having it off in the grass.

It was at this point that The Sexual Imperative threw in one of those unflattering comparisons with which nature programmes are fond of teasing us, by claiming that pygmy chimps - who suckle their young and copulate in a face-to-face position - are 'our closest living relatives'. As usual, though, there was some instant consolation to be drawn. These so-called human-alikes were still reassuringly far from developing their own railways, public sanitation systems, electricity grids, etc.

Following an extended series of trailers for The Sexual Imperative over Christmas, urging us, if memory serves, to 'do it with Channel 4', or some similar pun, many viewers will have tuned in hoping to witness an hour of soft pornography disguised thinly as scientific scrutiny. Or, if we were really lucky, not disguised at all. But pretty much the only bare flesh we saw was on the African naked mole rat, sort of a nude mouse which lives underground and is sweetly fastidious enough to toilet-train its young.

Otherwise the programme offered nature in all its horrible naturalness. And nothing forces sex from your mind quite as fast as close-up pictures of a snake swallowing a frog. Unless it's pictures of sundry gluey maggot- things squidging around in a termite mound. Frankly, there have been more erotic editions of On the Record.

What did we learn here? Sex is rooted in a determination to mix and preserve genes. Examining the weird feather-duster display that male birds of paradise go in for by way of foreplay, Gordon said we might think of these creatures as having 'gone into the world of advertising'. If this was the case, then it was the first advert for genes in ages not to exploit a forgotten pop song from the Sixties. The bigger questions went unanswered. 'Why are there eggs and sperm at all?' Given that just about the only other available option was to be an aphid and do the entire job yourself, maybe we simply got lucky.

To judge by the standards of the station's output so far, if Carlton had made The Sexual Imperative, chances are it would have been introduced by Mike Smith and called How Big is Yours? Storyline (ITV) is Carlton's investigative journalism spot and it was some relief to find that the programme wasn't modelled on Newsround. If anything, it dealt with its first tale (suspiciously high cancer rate round a chemical factory in Essex) soberly to the point of boredom. In a bold piece of scheduling, Storyline is up against EastEnders. As Hannah Gordon would probably tell us, for sheer concentration of pleasure, it probably won't match up.