Peter Braude: I have always believed that women go into menopause because they live too long. The issue is whether the climacteric and the postmenopause years are physiological. It seems to me that menopause is a pathological phenomenon and should be dealt with as such. Therefore saying that ‘we don't want HRT’ or ‘we need HRT’ is fallacious because it is not based on understanding physiology.

Jane Preston: It is interesting that you say that. Humans are not alone in having some kind of climacteric, although we have the longest post-reproductive lifespan of all the animals. Some other primates do seem to have a short period of cessation of fertility towards the end of life. The suggestion is that the animal has to achieve a certain length of lifespan in order for that to be seen. With increasing lifespan, primates gradually do show that increase in the post-reproductive lifespan. If any of them were to live close to our age then the suggestion is that menopause would happen. Whether it is pathology or not, I don't know. Data from women who have late menopause suggest they have better health fitness afterwards. That is, they live longer and appear to be healthier. One of the theories is about the need for grandmothers to be available to nurture their children.

Peter Braude: But what happens in primates — gorillas, chimpanzees and so on? Don't the older ageing females tend to get hounded out of packs?