Would it be possible to have an advanced technological society without abundant iron?
Howard Bobry
Port Townsend, Washington, US
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Yes, an advanced technological society would be possible without abundant iron, assuming, of course, that our essential biological needs were met. Comparing societies with and without plentiful, low-cost iron, it may just be that economic forces would drive the 鈥渉ave nots鈥� to become more advanced than the 鈥渉aves鈥�.
For most of human history, technology advanced without the use of iron. We moved on from bone and stone tools and weapons to using copper and then bronze. Iron, and its alloy, steel, are harder than bronze and superior for swords and cutting tools, but they are preferred for many other applications simply because they offer high strength at much lower cost. It is an economic, rather than technical, choice. Bronze could be used for bridges and tall buildings, as well as tools, engines and other machinery. A bronze Eiffel Tower, locomotive or ship? No reason why not, other than cost.
Bronze could be used for buildings and tools. A bronze Eiffel Tower, locomotive or ship? No reason why not, other than cost
Electromagnetic devices, such as transformers, inductors, generators and motors, are essential to our technological society. Without them, we would have no mains electricity, electrical machinery or electronics. Most are constructed from electrical steels (alloys of iron and silicon) or ferrites (iron-based ceramics) or both.
Could they be made without iron? Yes. Nickel, abundant in Earth鈥檚 crust, is a more expensive alternative but with superior performance. Yet continuing advances in semiconductor technologies facilitate the use of ever-smaller and less-expensive electromagnetic devices, effectively reducing nickel鈥檚 cost disadvantage. Our electrical and electronic industries could have evolved without inexpensive electrical steels and ferrites, but at higher initial cost.
Economics is a powerful driver of innovation. Would a lack of plentiful, cheap iron have hastened our development or use of other metals, composites, plastics and semiconductors, giving us an even more advanced society today? Has our abundance of iron driven us forward or has it retarded our technological progress? Either way, we egotistically call ourselves an 鈥渁dvanced technological society鈥�, no matter how laughable that may be to future historians.
Ian Simmons
Westcliff-on-Sea, Essex, UK
I suppose it is possible that, with sufficiently large deposits of copper and tin, an advanced, bronze-based civilisation could have developed if iron weren鈥檛 available.
However, it has long seemed to me that the limiting factor in a civilisation鈥檚 leap from pre-industrial to advanced is fossil fuel. Without a readily available source of combustible, energy-dense material, that transition would be impossible.
I suspect this is a major reason why we haven鈥檛 detected any alien civilisations. Even if all the planets in the universe had the right conditions for intelligent life to evolve, if a planet hadn鈥檛 gone through a stage with suitable conditions for an equivalent to oil or coal to form where it could be easily extracted, advanced technology would be impossible. There simply wouldn鈥檛 be the energy to get aliens through an industrial revolution.
We could be surrounded by alien races living in the equivalent of the early 18th century and never know it.
Garry Trethewey
Arkaroola, South Australia
I have two responses, neither of which is probably what the questioner is looking for.
The first is to wonder what the term 鈥渁n advanced technological society鈥� means. Like love or patriotism, attempts at a definition will be inconsistent and leave many gaps. So the fallback is 鈥淚鈥檒l know it when I see it鈥�. Trying to separately define 鈥渁dvanced鈥�, 鈥渢echnological鈥� and 鈥渟ociety鈥� throws up the same problems.
I am inclined to see the phrase as meaning 鈥減eople pretty much like us鈥�, although 鈥渓ike us鈥� is still pretty vague, and 鈥渢echnology鈥� as meaning impressive things 鈥� steel foundries, smartphones, but maybe not cups or socks.
So, I will go out on a limb and talk about honeybees. People don鈥檛 generally think of honeybees as an advanced technological society, but they tick all the boxes. They are very advanced in their technology (the way they do things, not the things they do it with). They have complex social interactions. And they do it without iron.
My second response is to point out that abundant iron isn鈥檛 the issue. Five per cent of Earth鈥檚 crust is iron. That is abundant. Accessible iron is more the point, with iron ore needing to be over 50 per cent iron to be economically worthwhile. Our advanced technological society is digging up concentrated sources of iron. It is similar with energy sources like coal and oil and with fertilisers like phosphorus. All these things have accumulated on geological timescales. Most iron ore formed 2.5 billion years ago, with very little created since. Much of our coal formed more than 300 million years ago.
So, when we send ourselves back to the Stone Age or leave the planet to cockroaches, what is the chance of another industrial revolution, without accessible iron, energy and fertilisers?
Bob McCrossin
Cooroy, Queensland, Australia
Iron is the end point of nuclear fusion in massive stars. The subsequent supernovae seed the universe with 鈥渕etals鈥� (astro jargon for elements other than hydrogen and helium).
New, massive stars that form in the next cycle have more metals in them. After enough cycles, rocky planets, probably life and maybe intelligent beings arrive. Not much iron means none of this happens, at least in a universe with our laws of physics, so the answer to the question is no.
We may need to start considering our digital legacy in our wills, especially any intellectual property we have created
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