In memory of Peter Fuller and our many conversations about the chain of being and neo-Darwinism.

In Basel the zoo is almost next to the railway station. Most of the larger birds in the zoo are free-flying, and so it can happen that you see a stork or a cormorant flying home over the marshalling yards. Equally unexpected is the ape house. It is constructed like a circular theatre with three stages: one for the gorillas, another for the orang-utans and a third for the chimpanzees.

You take your place on one of the tiers – as in a Greek theatre – or you can go to the very front of the pit and press your forehead against the soundproof plate glass. The lack of sound makes the spectacle on the other side, in a certain way, sharper, like mime. It also allows the apes to be less bothered by the public. We are mute to them too.

All my life I have visited zoos, perhaps because going to the zoo is one of my few happy childhood memories. My father used to take me. We didn’t talk much, but we shared each other’s pleasure and I was aware that his was largely based on mine. Together we used to watch the apes, losing all sense of time, each of us, in his fashion, pondering the mystery of progeniture. My mother, on the rare occasions she came with us, refused the higher primates. She preferred the newly discovered pandas.

I tried to pull her towards the chimpanzees, but she would reply – following her own logic: ‘I’m a vegetarian and I only gave it up, the practice not the principle, for the sake of you boys and for Daddy.’ Bears were another animal she liked. Apes, I can see now, reminded her of the passions which lead to the spilling of blood.

The audience in Basel is of all ages. From toddlers to pensioners. No other spectacle in the world can attract such a spectrum of the public. Some sit, like my father and I once did, lost to the passing of time. Others drop in for a few moments. There are habitués who come every day and whom the actors recognise. But on nobody – not even the youngest toddler – is the dramatic evolutionary riddle lost: how is it that they are so like us and yet not us?

This is the question which dominates the dramas on each of the three stages. Today the gorillas’ play is a social one about coming to terms with imprisonment: life sentences. On the second stage, the chimpanzees’ show is cabaret: each performer has her or his own number. The orang-utans are performing Werther without words – soulful and dreamy. I am exaggerating? Of course, because I do not yet know how to define the real drama of the theatre in Basel.

Is any theatre possible without a conscious ritual of re-enactment? All theatre repeats, again and again, what once happened. Often those who are dead are brought back to life on the stage. Mere reflex actions do not make theatre; but wait –

Each stage has at least one private recess where an animal can go, if she or he wishes to leave the public, and from time to time they do so. Sometimes for quite long periods. When they come out to face the audience again, they are perhaps not so far from a practice of re-enactment. In the London zoo chimps pretend to eat and drink off invisible plates with non-existent glasses. A pantomime.

We can see that chimpanzees are as familiar as we are with fear. The Dutch zoologist Dr Kortlandt believes that in fact they have intimations of mortality. We are at least on the threshold of theatre.