But one thing that seems pretty clear when we look at human religion is that it's highly tied in with human culture. So if, as seems to be the case, culture's governing a lot of what whales do, it's perhaps not an unreasonable hypothesis to think that it's got elements of...what I guess you'd call the supernatural.

Studying the behavior of large whales has been likened to astronomy. The observer glimpses his subjects, often at long range; he cannot do experiments, and he must continually try to infer from data that are usually inadequate.

What I mean by it, and roughly what most biologists who talk about culture mean by it, is either behavior itself, or information that leads to behavior. Information that is picked up through social learning - so, from being with, watching, being taught by others. It's a way that individuals behave or get information about how they will behave that comes directly from the behavior of others.

Psychologists would say that the only two important forms of social learning are imitation and teaching, and they will spend time trying to figure out if animals imitate or teach. Sometimes they find they do; sometimes they find they don't. And so that's kind of the level of controversy there. Biologists would include imitation and teaching and a range of other kinds of social learning. So we would call that culture, whereas the psychologist wouldn't.

Humans are particularly interesting; our culture is incredible, there's no doubt about that. In many respects, no other species matches ours. But in quite a few respects, they do, and that can help us, perhaps, to better understand our own culture. We look at the ways humans are similar to other animals, and at the ways they differ, rather than just saying, "We have culture and you don't."

I don't think in biology it's very controversial at all. Whether certain behavior is culture or is not culture is argued. I think virtually all biologists would agree that some animal behavior is culture. Bird song is a good example.

I was very lucky. I was just finishing my PhD at Cambridge in 1981. This opportunity came up because whaling was drawing to an end. There was the prospect of a moratorium, and one of the arguments that was brought up, especially by Japanese whalers, was that, if we didn't have whaling, we would know nothing of whales. All the science depends on having dead animals, they argued, so that's one of the benefits of the whaling industry.