Why is it that in my classes we always seem to return to the same old debates? Perhaps because whatever else changes, one constant remains: it's the same old teacher.
This time the topic was that perennial favourite: do animals have language? "It depends," I say, as I always do, "what you mean by language." My students can't reply out loud but their faces say it for them: "Oh, shut up!"
Because what they want to discuss is how their dogs understand everything they say, and that by wagging their tails and twitching their ears these pets can construct perfect sentences in three separate tenses. "Oh yes," I say, "and next you're going to tell me that when you point enquiringly at a tree trunk, little Rover always says `bark'."
The intellectual in the class - the one who listens to Radio 4 - pointed me to a podcast of a programme on animal personality. Later in the week I gave it a listen, and discovered a world I had no idea existed. The programme looked at research that had been carried out into a variety of creatures - not just primates, but birds, hermit crabs and even colonies of sea anemones - who apparently have their introverts and extroverts just like the rest of us.
Actually, "personality" might be stretching the term, because what the researchers were really measuring were degrees of timidity and boldness. One study, conducted using flocks of great tits, found that the bolder birds - the extroverts - explored new territory more quickly and aggressively than their more cautious and introverted peers. They were also speedier and more successful in foraging for food.
The introverts, however, although less buccaneering in new situations, displayed a greater level of caution when looking out for predators.
For a while, the researchers puzzled over these variations. In evolutionary terms, wouldn't natural selection mean that one personality type - presumably the bolder one - would predominate and "breed out" the more cautious characteristics? But then they also observed that the most successful flocks of great tits had a good balance of both types. While the alpha-males of the tit world were scooping up all the grubs, the wimpier types were keeping an eye out for the hawks and buzzards.
Which brings us neatly back to the classroom. Or, more precisely, the staffroom. Because in education, too, you surely need a combination of personalities to be successful. It's the entrepreneurial types - the ones who are forever finding fresh sources of funding or setting up ground-breaking courses - who tend to get the glory. The problem is that once they have their shiny new courses up and running, they often lose interest. What they want is a fresh challenge, not the day-to-day tedium of seeing the thing through. For that you need the plodder, the "steady as you go" type who will make sure the classes fit the rooms allocated and ensure that students are registered for their exams in time.
The odd lucky individual is good at both. But these are few and far between, and one thing I know for certain is that I am not one of them.
Stephen Jones is a lecturer at an FE college in London