Thursday, May 3, 2007
The Evolution of Sickness
Just yesterday I came down with a horrible case of the flu, which is why I am writing this post. Usually when we are sick, we do not spend much time thinking about what the evolutionary functions of our symptoms are. If we do think about it, we usually think about it from our own perspective, not the perspective of the germ.
So, why do we get sick? What is the adaptive function of having the diarrhea and vomiting? Why do we get a fever? Randolph Nesse and George Williams present an evolutionary explanation to these questions in their book, Why We Get Sick: The New Science of Darwinian Medicine.
The short answer to the question of why we vomit and get the diarrhea when we have the flu is because it is adaptive for the germ. It is in the germ’s best interest to spread itself and it just so happens that causing us to vomit and diarrhea are effective methods for achieving this.
The fever, on the other hand, is not in the germ’s best interest. It is an adaptive function of the body, an attempt to kill the germ.
To learn more about Darwinian Medicine, check out this website: http://darwinianmedicine.org/
Also, read Why We Get Sick.