Scientist and author Jarod Diamond answers a list of scientific questions.
Can the world's population keep on growing without any threat to the future of the planet?
Of course not. If the world's population kept on growing at its current rate, there would be 10 people per square yard of land in 774 years, and a mass of people equal to the Earth's mass in less than 2,000 years. Long before that, we would have problems less serious than 10 people per square yard, but serious enough to worry about; we already have serious problems now.
Is China's rise to being the world's pre-eminent superpower unstoppable?
Not only is China's rise to being the world's pre-eminent superpower not unstoppable; it is unlikely. By starting from a low level of development and having lots of people, China is able to achieve apparently spectacular growth at present. But its political and economic system is far inferior to Europe's and America's at mobilising human thinking to solve societal problems.
Is Western education guilty of emphasising the arts at the expense of science?
Not at all. Instead, just look at most Western universities, at the disciplines for which they are building buildings, and at the disciplines in which they are appointing most new faculty. Western education today is guilty of emphasising science at the expense of the arts.
Is the religious impulse hard-wired into humanity?
The religious impulse is not hard-wired, because many people live happily and prosperously as atheists. But there are big reasons (I've counted seven of them) why the religious impulse is nevertheless widespread, and why virtually all known human societies have had religions.
Which ancient tribe can the modern world learn the most from, and what are those lessons?
The modern world can learn from almost all ancient tribes. The cases of mass slaughter should make us appreciate that under modern state governments - even allowing for such events as Hiroshima - such instances are very much on the decline. The good things we can learn include caring for the old and infirm. I am thinking of the skeletons found in Eurasia dating back 30,000 years that show people survived for some years with broken bones - and the reason was because they were looked after.
Does medical history suggest that there are as yet unknown diseases out there which will afflict humanity? If so, can we do anything to prevent them?
Not only medical history, but also sampling of wild animals, of the individual men who hunt them, and of the friends and neighbours of those hunters demonstrates that there are thousands of microbes out there in the microbe reservoir of wild animals ready to make the leap to humans. Most, perhaps all, of the major disease killers of human history (such as smallpox and measles and Aids) arose from pathogens of wild animals. A promising way to prevent them is to monitor the pathogens of wild animals and of their hunters and of the hunters' associates, and to attack a new disease in the earliest stage of its spreading to people. Aids could have been stamped out far more easily 40 years ago than it can today.
Are specifically Western conditions such as obesity irreversible?
First of all, conditions such as obesity are not specifically Western: they're universal, afflicting any human population that eats more and exercises less. Second, many of us know from personal experience that, fortunately, those conditions aren't irreversible. If we consume fewer calories, eat more of some things and less of other things, and exercise more, we lose weight.
Does our collective failure to tackle climate change condemn us, like the Easter Islanders, to become a vanished civilisation?
I would say that yes, climate change does threaten us and whether we come out of it intact is up for grabs. But we do have huge advantages over the Easter Islanders. We have climatologists and books, and people are at least talking about the problem.
When was the best time in human history to have been alive?
Either today, or else a few decades ago before the rise of computers and email.