Humans Versus Elves

Generated by Gemini 

We all know that elves live far longer than humans. Let's say that elves live on average 900 years but humans live on average only 90 years. In our imaginary world, let's say that the populations of both species are equal at one million each, with roughty equal numbers of males and females. Humans and elves cannot produce viable offspring but humas couples on average produce 2.01 babies during whereas the elves produce on average 1.99 babies during their very lengthy lifetimes. Thus we have:

• Humans:Reproductive Rate: 2.01
  Growth of 0.5% per generation
  Generation Time: 30 years
  
  
• Elves:Reproductive Rate: 1.99$
  Decline of 0.5% per generation)
  Generation Time: 300 years

What happens to these two starting populations over the next 50,000 years? Well, the differences are startling. Chart 1 and Table 1 tell the story.

Chart 1: produced by Gemini

Table 1: produced by Gemini

The elf population after 50,000 years has dwindled to less than half its original size (433,691) while the human population has soard to over four billion (4,074,768,381). This was just a little comparison that occurred to me when I was lying in bed and trying to get to sleep. It's remarkable how a relatively small difference in reproductive rates (one slightly above replacement level and one slightly below) can produce such divergence over extended periods of time. Of course, the real life human replacement level for humans is close to 2.1 but the scenario I've depicted is just imaginary and the realisation of a nocturnal thought experiment.