Keep Your Eye on the Older Population

For virtually all of human history the real focus of societies has been on the younger population. The dramatic declines in mortality over the past several decades have, of course, accelerated the increase in the number of older people, while the drop in the birth rate has steadily increased their share in the total population. Such was the reminder this week from the United Nations Population Fund (UNFPA) as it celebrated "The International Day of Older Persons." BBC News reported on the event:

"Today we have one in nine persons aged 60 or over," says the UNFPA's Dr Ann Pawliczko, "but by 2050 it'll be one in five, and by that time there will be more older persons than those under 15 years."

The UN sees these statistics as a cause both for celebration because more people are living longer, and some concern because the change presents an economic and social challenge.
Dr Pawliczko would like see more countries prepare for the coming demographic shift. After all, she says, there is no doubt it is happening.

"We can be very certain about the numbers for 2050 because persons who will be aged 60 in 2050 are already born. This not speculation."

But there is still considerable speculation about what will happen to the birth rate, in both developed and developing nations.

"Historically, fertility has been falling across Europe," says Professor Jane Falkingham, director of the ESRC Centre for Population Change at Southampton University. "But actually if we look at the most recent period, the last 10 years or so, we see rises in fertility in the most advanced countries."

Evolutionary biologists might not be surprised by this. The idea that as we get richer we have fewer children is, from their perspective, very odd. Normally natural selection produces individuals who are good at converting their resources into lots of fertile descendants.

It's a demographic paradox that in the past few centuries, developing societies haven't been filled by families who raise as many kids as they can possibly afford.

Of course, this may not make a huge difference to world totals, since the populations of the developing nations far outnumber those of the richer nations. Still, it is sobering to think that even with the current UN projections from their Population Division, we may hit 10 billion people by 2057--less than a half century from now.