Daniel Quinn often gets criticized on E2 for his ideas on
population growth and
agriculture. In fact, teleny has posted quite a rational
criticism of Quinn and his work in several locations here. I would like to spend a few moments addressing these arguments on the subject of
Daniel Quinn’s ideas.
The first argument involves Daniel Quinn’s pointing out that food supply relates directly to population growth. The detractors state many facts and figures about food supplies in certain countries do not necessarily relate to population growth in these countries. On this count, Daniel Quinn agrees with them. He repeatedly stated that food growth in a country doesn’t mean population growth in that country, it just relates to population growth somewhere. Food that Nebraskan farmers make and the US population does not eat gets shipped to somewhere else, otherwise it would rot unsold and farmers would decrease their production, something we know they do not do. They often point out that the countries with the poorest food production have the highest birth rates. However these countries most often receive the foreign aid and food surpluses of the west. Then they argue that Daniel Quinn wants us to stop foreign aid, which he never stated once. The only comment he ever made about food production stated that we needed to make less of it each year in order to have less people. Food aid would still continue, but as a species we would decrease the amount of food each year to effect the changes that Daniel Quinn says must come about in order to lower our population.
Modern biologists agree with Daniel Quinn that food supply and population growth follow one another. In the case of a predator-prey situation, which humans and their food engage in, Lotka-Volterra equations show that predator population gets linked to prey population. The model, which most biological scientific evidence backs, gets summarized as follows.
P(t) = prey population at time t
Q(t) = predator population at time t
R1 = prey’s Malthusian factor, determined by the prey’s ability to reproduce
R2 = predator’s Malthusian factor, determined by the predator's reproductive ness
K1 = prey’s carrying capacity, which gets set to the upper limit of prey the environment can hold
K2 = predator’s carrying capacity
The equations show that
P(t+1) = (R1 * P(t) * K1 ) – P(t) * Q(t)
Q(t+1) = -(R2 * Q(t) * K2) + P(t) * Q(t)
Often feeding factors f1 and f2 get put on the last term and the models we use now have much more complexity, but the basic Lotka-Volterra equations get held in the highest esteem by biologists and all consider them sound.
As far as scientists have seen, all animals follow this model, including humans. Nowhere did Daniel Quinn state that the rats in his thought experiment “instinctively knew” anything about how to curtail their population growth. He only said that population growth follows these mathematical models.. What these equations mean for human stems from the additive term at the end of the equations. The predator’s population grows based on the food supply of the prey. The first equation states that prey’s population will decline based on the number of predators however Lotka-Volterra represents predator/prey relations in an ideal limited environment. What humans do in the real world stems from us artificially increasing the prey population via what Daniel Quinn calls Totalitarian Agriculture.
This brings us to the second point which often gets bashed Daniel Quinn’s idea of agriculture. He never stated that “agriculture means only growing food”. In fact, it seems likely that humans have engaged in agriculture for far longer than the 10,000 years since the Neolithic period where our population growth boon started. Daniel Quinn repeatedly stated that agriculture only means “encouraging food growth of things you enjoy eating”. American Indians became well known for their agriculture, however they engaged in a distinctively different form of agriculture, and thus their population remained relatively stable on this continent for the 10,000 years before coming into contact with Western Civilization (baring the initial spread of humans on this continent). He did state that our culture engages in a particular style of agriculture, which he labeled Totalitarian Agriculture.
Totalitarian Agriculture means encouraging your food supply growth at the expense of all other life forms. It meant that to ensure that we have more cattle each year, we killed all the wolves. To ensure that we had more chickens each year, we killed all the foxes. To ensure that we had more crops each year, we sprayed them with poisons so other animals couldn’t eat them and we fenced them in so animals couldn’t get to them. Each year for the past 10,000 years we have ensured that our food supply must grow by denying other parts of the ecosystem from eating our food. For this reason, humans have broken out of the stabilizing force of the negative P(t) * Q(t) part of the Lotka-Volterra equations. Which works out well for human population except for one important factor. We require the ecosystem to survive on this planet and denying it food means that it will die.
Humans need the oxygen from the plants and algae. We need the ecosystem to provide nitrogen for our growing plants. We need healthy ecosystems to ensure that the topsoil doesn’t erode and turn the planet into a desert, which it seems to rapidly change into recently. Daniel Quinn’s entire point revolves around us not understanding that we currently deny the ecosystem an inordinate amount of food and we continue to decrease that amount each year. This course ends in disaster for the human race and probably all of the larger mammals on the planet.