Expert: Dana Krempels, Ph.D. - 9/29/2008

Question
why does the population grow slowly for most of human existence....???


Answer
Dear Ashley,

Humans, like any other animals, have a great deal of mortality from pathogens, lack of food, predation, etc.  For most of our history, we didn't have medicines or shelter.  

All that changed with the Industrial Revolution, which saw the advent of antibiotics, sanitation, more sophisticated shelters, fossil-fuel based power, etc.  All these things not only improved human *quality* of life, but also its duration.

In developing countries, human populations reproduce at a much greater rate than those in developed countries, but they also have a much higher mortality rate due to those ancient scourges (disease, starvation, lack of shelter, etc.) than people in the "modern" world have.  But we are still incredibly good at displacing other species to make room for more of our own.  

The question isn't really "why did human population grow so slowly for most of our existance?" because that's the natural order of things.  The real question is "Why is human population growth rate skyrocketing now, and since the mid 1800s?"  The answer is:  The Industrial Revolution and all its lifesaving technologies.

Hope that helps.

Dana