The World’s Plummeting Fertility Rate

Of course it will, that is not what governments are worried about. The problem with a shrinking population is shrinking tax revenue, shrinking GDP, and worst of all for anything corporate, shrinking consumer spending.

Perhaps a cynical view but the worrying at Davos has nothing to do with planet Gaia or Humanity as a whole.

The main worry I have is how we are going to manage financially. For hundreds of years, we've only had growing world population and it has been a driver for much economic growth. Industrialism and the increasing world population has gone hand in hand. Will we see more inflation now, when there will continuously be smaller working populations? What about investments: Will it be more difficult to attract investment when many markets are naturally shrinking due to shrinking populations?

There are very strong incentives to try and "keep the party going", especially in economies (say Canada/Australia/NZ) that look basically like a thin layer of life support wrapped around an extractive housing market.

The way I see it, humans are animals and the average fertility of this species of animals has recently gone down radically in most places due to changes in it's habitat that has reduced its fitness.

This has happened to millions upon millions of species in the past. One out of three things can happen:

1) The species goes extinct. This is more likely for species that are already pressured by competition from other species, since their ecological niche may go away completely.

2) The habitat reverts to a state where the average fitness of the species is high enough to sustain the population. This often happens in cycles for species like lemmings, where overpopulation periodically leads to population collapses.

3) If neither 1 nor 2 happens quickly, most species will adapt to the changes in their habitat. Often this happens by changing the relative frequency of genes in the gene pool towards those more fit to the new environment. This is arguably the main benefit of sexual reproduction. Sometimes a few mutations may also help adaptation.

Given the current size of the human population, (1) is not very relevant (or if it happens, it's for another reason, such as runaway AI). (2) could always happen, for instance if society collapses to a point where condoms are not available and there's not police available to prevent rape.

But if society remains relatively stable, I believe (3) will happen within 5-50 generations (starting in about 1950, meaning we're about 3 generations in). If I'm right, we will soon see that some genes are associated with higher fertility, and that the frequency of those genes keep going up over the generations. Since this is an exponential process, it starts out slowly.

I'm not really worried about either way. I'm long dead by then or dead somewhat earlier as not enough funds go to keeping me alive.

The main problem is not a shrinking population but an aging one. As long as TFR is below replacement the proportion of elderly increase forever. In the US right now there are 3 worker for every retired person. By 2030 it will be 2 workers per retiree. That's a 50% increase and it will continue to get worse until TFR increases.

An increasingly non-working population will have a lot of bad effects.

We are always looking for societal explanations and ignore possible effects of biology / chemistry. It is unpleasant to realize that we are biological machines that are fairly resilient, but will still break down or malfunction in certain environment.