the nose knows
if you commit physical violence upon an acacia tree it will increase the tannin content of its leaves. at the same time it will communicate a danger signal to the trees around it and they too, in turn, will increase the tannin in their leaves. the communication occurs through a sense of smell. this sort of communication may also exist in humans and the chemicals are not only olfactory but things that don’t have a smell but exert an influence as if they did. the device responsible is located in our nose and has come to be called jacobson’s organ. it is our sixth sense and among its many important functions is to initiate the mating function. (lyall watson, “jacobson’s organ and the remarkable sense of smell”, isbn 0393049086) (2005)
(source)
I own this book even, but it’s written in boring “sciencese” so I pretty much slept through it. ;D Should pull the damned thing out and see what other informational jewels there are to read!
