Who’s aping whom?

For a practical at medical school on the subject of the nervous system, it was thought unwise to wire students up to a live electrical circuit, so we used worms instead. The task was to measure lumbricus terrestris’s giant neurons as they fired. My worm’s bruise-coloured rings concertinaed in a final effort to escape before I made the necessary incisions, stuck pins through its body, and connected its extremities to the electrodes. The paper instructions suggested: ‘You can if you wish cut off the worm’s head.’ I guess we were lucky; apparently similar lessons used to be taught using live dogs.

I’ve always disliked the spirit of historical re-enactment involved in amateur lab work. You try to replicate experiments first carried out in the 1960s, for which you already know the answers. As I worked on the worm, the voltmeter sat persistently at zero. How depressing and painful, I thought, noticing my anthropomorphic reflex to project my feelings onto this poor creature. Though surely it’s not inconceivable that my worm and I both felt blue.

Charles Darwin was one of the first scientists to take such ideas seriously. The Expression of the Emotions in Man and Animals, published in 1872, had a blasphemous idea at its heart: emotional complexity is not exclusively human. Darwin was well acquainted with Victorian prejudices and knew it would be less threatening to highlight the human aspects of animals, rather than the animal aspects of humans. He also chose subjects that were comfortably familiar in domestic settings, such as dogs and cats.

Although academic circles have been quiet on the subject, the issue of animal emotions has never really gone away. By 1987, The Oxford Companion to Animal Behaviour made the concession that ‘animals are restricted to just a few basic emotions’. Today the question is not whether animals have emotions, but how scientists afforded to overlook them for so long.