5 ms·

Pretty sure we'll stop wanting to reproduce at the required rate long before food/resources becomes the real issue (which isn't to say starvation etc. isn't lik

Pretty sure we'll stop wanting to reproduce at the required rate long before food/resources becomes the real issue (which isn't to say starvation etc. isn't likely to be a major problem for much of the world's population in coming decades, but it'll make less of an impact on population growth than the rate we choose to reproduce at).

trashtester 3y ago
Beyond the clouds, the sky is always blue. But look further, and space is black as night. Humans are a species of animals. Recent environmental changes has caused a sharp decline in evolutionary fitness (=reproduction rate) for this population. This has happened to millions of species in the past, and in many (if not most) cases, the population adapted to the new environment, and the fitness grew back to or beyond replacement rate. Also, this can happen quite a lot faster than some seem to imagine. While it takes a long time for completely new mutations to make it into the gene pool, the gene pool already contains a huge diversity of genes coding for different types of traits, including mental traits. Often, all that is needed to adapt to a new environment, is for the relative frequency of these genes to change. For instance, many people seem to have a built-in oxytocin response when around young children. A boost in frequency to all genes promoting/strenghtening this mechanism may eventually make the need-to-have-baby emotion in most women stronger than the need-to-have-orgasm drive in the horniest of 18-year-olds. And if these genes are already in the gene pool, just with a low frequency, they could easily become dominant over 10-40 generations. In other words, if at some point the kinds of environmental change that cause population decline slows down, I don't think it's likely that the birth rate stays below replacement forever. (If it does, we'll go extinct, of course).
- wizofaus 3y ago
  Forever is far too long a time to make useful predictions about. But in the meantime... https://www.theage.com.au/lifestyle/health-and-wellness/absolutely-stunned-sperm-counts-are-falling-faster-than-ever-20230606-p5deav.html https://www.theage.com.au/lifestyle/health-and-wellness/abso...
  - trashtester 3y ago
    Sperm count has to fall quite a bit further before it becomes a bigger limiting factor than women actively chosing to not make babies. Also, I'm not making predictions about "forever". Rather, my prediction is that the reproduction rate is likely to come back above the replacement rate very quickly, compared to evolutionary time. My guess is somewhere between 100 to 1000 years, if human societies go on approximately like today, and we don't have some kind of apocalypse, AI takeover or totalitarian world government.

trashtester 3y ago

Beyond the clouds, the sky is always blue. But look further, and space is black as night. Humans are a species of animals. Recent environmental changes has caused a sharp decline in evolutionary fitness (=reproduction rate) for this population. This has happened to millions of species in the past, and in many (if not most) cases, the population adapted to the new environment, and the fitness grew back to or beyond replacement rate. Also, this can happen quite a lot faster than some seem to imagine. While it takes a long time for completely new mutations to make it into the gene pool, the gene pool already contains a huge diversity of genes coding for different types of traits, including mental traits. Often, all that is needed to adapt to a new environment, is for the relative frequency of these genes to change. For instance, many people seem to have a built-in oxytocin response when around young children. A boost in frequency to all genes promoting/strenghtening this mechanism may eventually make the need-to-have-baby emotion in most women stronger than the need-to-have-orgasm drive in the horniest of 18-year-olds. And if these genes are already in the gene pool, just with a low frequency, they could easily become dominant over 10-40 generations. In other words, if at some point the kinds of environmental change that cause population decline slows down, I don't think it's likely that the birth rate stays below replacement forever. (If it does, we'll go extinct, of course).

wizofaus 3y ago
Forever is far too long a time to make useful predictions about. But in the meantime... https://www.theage.com.au/lifestyle/health-and-wellness/absolutely-stunned-sperm-counts-are-falling-faster-than-ever-20230606-p5deav.html https://www.theage.com.au/lifestyle/health-and-wellness/abso...
- trashtester 3y ago
  Sperm count has to fall quite a bit further before it becomes a bigger limiting factor than women actively chosing to not make babies. Also, I'm not making predictions about "forever". Rather, my prediction is that the reproduction rate is likely to come back above the replacement rate very quickly, compared to evolutionary time. My guess is somewhere between 100 to 1000 years, if human societies go on approximately like today, and we don't have some kind of apocalypse, AI takeover or totalitarian world government.