It is reasonable to say that Humans have not been around for 200,000 years

Argument: Population Growth My opponent pointed out that the citation he included in his argument demonstrates that populations growth at a doubling rate of approximately 45 years. First, no where in the article does it say that all populations since man has walked on the Earth have doubled every 45 years. In fact, the nature of the article is clear in its title: 2.1.1. The world population growth in the last three centuries. The author only addresses population growth for the last three hundred years which works out to be 5 x 10 to the minus 4 (format would not allow for scientific notation), or .0005% of the time span from time zero to time plus 200,000 years. The author never suggests that this same analytical approach can be used to extrapolate population growth throughout the ages. Statistical Calculations My opponent suggests that populations would have to be on the verge of disaster frequently in order for the catastrophic event theory to be valid. A literature search of prehistoric population growth revealed the following: Hominid population estimates It is estimated that the average life span of hominids on the African savanna between 4,000,000 and 200,000 years ago was 20 years. This means that the population would be completely renewed about five times per century,[citation needed] assuming that infant mortality has already been accounted for. It is further estimated that the population of hominids in Africa fluctuated between 10,000 and 100,000 individuals, thus averaging about 50,000 individuals. Roughly multiplying 40,000 centuries by 50,000 to 500,000 individuals per century, yields a total of 2 billion to 20 billion hominids, or an average estimate of about 10 billion hominids that lived during that approximately 4,000,000 year time span.[1] https://en.wikipedia.org... Although catastrophic events may be few and far between, there are other factors which impact population growth in the ancient world. Some of these are: Life span: It is estimated that the life span of the average person in the ancient world was approximately 20 years. Assuming that humans at that time were able to reproduce approximately 40%* of that life span, this would mean that the average person would have about six years to reproduce. By contrast, during the last three hundred years, life spans have ranged from approximately 50 to 75 years. Using the same calculation as above, that would allow humans a reproduction period of approximately 38 years of reproductive activity, or 63% of total life span. The impact of increased time for humans to reproduce is obvious - more time, higher reproduction rates. *Assumptions: A person was capable of reproducing from the age of 12. Prehistoric man fertility span: 20 years " 12 years = 8 years Modern man: Mean life span = 60 years. Number of fertile years: 60 -10 = 50 (this allows for the cessation of fertility at age 50). Fertile time during life span: 50 " 12 = 38 years. Calculation for Prehistory Man: 20 " 12 = 8 years, or 40%, for reproductive time Calculation for Modern Man: 50 " 12 = 38 years, or 63% for reproductive time Given the estimations above, it's highly unlikely that the growth of any population prior to the AD time frame would even come close to doubling every 45 years. Once again, I will point out that there is no real data to substantiate the numbers definitively. However, archaeological evidence which includes the fossil records suggests that a much lower rate of population growth is more likely. The Fossil Record and Dating Methodology As pointed out in my first argument, radiometric dating methods have been validated mathematically and empirically. This is a topic that requires a more detailed debate and isn't the topic of this one. I would be happy to engage in that debate with the caveat that I am a physicist. A challenger would have to be up on the mathematics and history of these developments. In conclusion, the evidence provided by my opponent in no way validates the assumption that all populations have doubled at any particular rate. Extrapolation of current calculations on 300 years of data isn't statistically relevant for the reasons given above. The linearity alone of that assumption is highly unlikely " nothing moves in a straight line forever. The available data is insufficient to draw conclusions about previous population growth. Even the archaeological evidence and fossil record cannot pinpoint statistically significant population dynamics as the research is an ongoing process. Therefore, the positions of my opponent are invalidated given the evidence presented herein. References: 1. ^ Angela Piero and Alberto Piero (1993), The Extraordinary Story of Human Origins, New York: Prometheus Books, p. 194