Our lungs are there for respiration and not for waste treatment. The function of waste treatment is done by our kidneys. In the same way the heart does not detoxify poison, it pumps blood. The detoxification of poison is done by the liver. So if we look at the body we find that every organ of the body has a specific function for the smooth functioning of the body. So in an analogy, evolutionary psychologists opine that different neural circuits perform different functions:

“For the same reason, our minds consist of a large number of circuits that are functionally specialized . For example, we have some neural circuits whose design is specialized for vision. All they do is help you see. The design of other neural circuits is specialized for hearing. All they do is detect changes in air pressure, and extract information from it. They do not participate in vision, vomiting, vanity, vengeance, or anything else.” (Tooby and Cosmides)

99% of our species evolutionary history since the last 10 million years had been spent in a hunter-gatherer society, so all that has happened after that – be it technology, language or later the industrial revolution or the computer revolution – is minuscule as compared to the 99% of our evolutionary history. What is the implication here? Tooby and Cosmides believe that “that means that our forebearers lived in small, nomadic bands of a few dozen individuals who got all of their food each day by gathering plants or by hunting animals. Each of our ancestors was, in effect, on a camping trip that lasted an entire lifetime, and this way of life endured for most of the last 10 million years.”