"What has caused the recent super-exponential rise in world population? Before the industrial revolution both fertility and mortality were comparatively high and irregular. The birth rate generally exceeded the death rate only slightly, and population grew exponentially, but at a very slow and uneven rate. In 1650 the average lifetime of most populations in the world was only about 30 years. Since then, [hu]mankind has developed many practices that have had profound effects on the population growth system, especially on mortality rates. With the spread of modern medicine, public health techniques, and new methods of growing and distributing foods, death rates have fallen around the world. […] On a world average the gain around the positive feedback loop (fertility) has decreased only slightly while the gain around the negative feedback loop (mortality) is decreasing. The result is an increasing dominance of the positive feedback loop and the sharp exponential rise in population […]."