Last night's viewing - Planet Ant: Life Inside the Colony, BBC4; Heading Out, BBC2

Remember ant farms? Two sheets of glass filled with earth and topped off with a cartoon rendering of a Midwestern cattle ranch? In my experience, they seemed to offer a matchless way for a budding entomologist to study the process by which live ants turn into dead ones – or, just occasionally, how excitable human matriarchs can become when the ant colony breaks free and heads across the kitchen for the sugar bag. Having watched Planet Ant: Life Inside the Colony, though, I can see that these rudimentary affairs barely deserved the name of ant farm.

Planet Ant boasted an ant megalopolis, a multi-layered, tunnel-connected super city with convenient access to fresh greenery and utilities. Occupying it was a colony of leafcutter ants from Trinidad, saved from extermination at the hands of a local fruit grower who took a dim view of the colony's ability to consume a cow's weight in vegetation every day.

Digging them out wasn't easy, since the team had to find and preserve the queen in order for the transported colony to thrive. It was like finding a needle in a haystack while most of the haystack is busy biting you. But with the help of a man who apparently specialises in digging up ant colonies for Western science institutes (I'd love to have seen him on What's My Line?), the ants eventually made it to their new home in the Glasgow Science Centre, where Dr George McGavin, the BBC's tame entomologist, could rhapsodise over the social arrangements.

He's not the first person to do so, of course, as another contributor pointed out – ants having provided metaphorical fodder for human social theorists of all kinds. The Victorians greatly admired them because of their model of "mutual aid" and, one guesses, their unquestioning occupation of social rank. Others took them as an emblem of soulless industrialisation.

The human/ant parallels will only go so far. It's difficult to think of an equivalent for fire ants' ability to construct unsinkable rafts from their own bodies and I challenge anyone to come up with a social analogy that draws on the Asian weaver ants' habit of building houses using their infants as glue guns. But the way in which ants can convert simple algorithmic rules into highly efficient kinds of behaviour did turn out to have a human application. They use this system to forage for food and find new nests, but we use it – having digitised ant behaviour and pheromone trails – to work out the least costly way to deliver goods.

It's called ant-colony optimisation and it has apparently saved at least one American corporation millions of dollars in fuel costs. Clever ants, the anthropomorphically minded are inclined to murmur at such moments. Clever us, I say, for having worked out how they did it and how we could turn it to our own advantage. Planet Ant, incidentally, was fascinating – it's only drawback being that all those close-ups of scuttering ants may have induced formication in the more sensitive viewer.

I have a feeling that viewers are now attracted to new comedies in a process similar to ant-colony optimisation. A few try it out and if they like it and return they leave a pheromone trail that attracts others, until eventually there's a swarm clustered round every juicy new episode. Not sure that it's going to happen with Heading Out, Sue Perkins' comedy about a vet plucking up the nerve to tell her parents she's gay, perhaps because it continues to strain credulity with its comic plots.

This week, one running joke concerned her friend Jamie's attempts to become more blokey, an ambition that never remotely threatened to become believable. On the other hand, the surreal moments at which the whole thing turned into a soulful French film, complete with subtitles, were quite funny. The latter seemed true to a state of mind, the former just faked one for the sake of a joke.