Evolution and Healing

This book puts forward the case that a thorough-going understanding of human evolution by medical professionals is likely to give us better medicine. The book starts by explaining the essentials of Darwinian natural selection and then embarks on showing how these ideas illuminate the reasons why we become ill.


The front runner example is the perpetual war that goes on between host and parasites. Like other organisms, humans are constantly under attack from bacteria and viruses. We have evolved complex defence systems against them and they, in their turn, have evolved ever more sophisticated weapons of offence. A continuous evolutionary arms race is under way. It is our genes which enable us to respond in this way, but there is an inevitable cost; the defence mechanisms can cause disease as well as prevent it. Autoimmunity, in which the body’s defence mechanisms are turned against its own tissues, is an example of this.


Another example is allergy, for it is thought that allergy may be part of the defence mechanism against cancer. (Cancer cells can be thought of as parasites that are produced internally by the body instead of invading from outside.) Psychological disorders may also have an evolutionary origin: anxiety, for example, may be an exaggeration of the fear mechanism that protects us from dangerous situations. Ageing occurs because natural selection has no need for us once we have passed reproductive age, so mechanisms for very prolonged survival have not evolved.


These ways of looking at disease have important philosophical implications. Disease doesn’t result from random causes or malevolent forces, it arises mostly from past natural selection. As Randolph Nesse and George Williams say, this makes disease at once more and less meaningful. Science does not offer us a metaphysical explanation for the existence of disease. But it does offer us an intellectually satisfying account. And the evolutionary approach to medicine suggests numerous new directions for research, which the authors outline.


This is a book to be welcomed by those interested in the fundamentals of medicine. Check if it is in stock at your local library by consulting the online catalogue at https://www.sllclibrary.co.uk/cgi-bin/spydus.exe/MSGTRN/OPAC/BSEARCH



320 pages in J.M. Dent & Sons Ltd.

First published 1995

ISBN  978-0460861403


Randolph M. Nesse

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