Men of Rock

Not music—but geology.

I’ve been watching BBC Scotland’s recent series Men of Rock on iPlayer. Presented by Iain Stewart, it covers the history of geology, and how we have come to learn about the past, through the landscape of Scotland.

Overall an excellent series, with a lot of really interesting facts, even for someone who knows a bit about geology. There is also some fantastic aerial footage of Scottish hills and glens, although someone in the production team obviously though that people’s attentions spans were too short just to show straight footage, so after 10-15 seconds, the footages annoyingly speeds up for a couple of seconds.

The show has quite a strong Scottish slant: it is about the Scottish landscape, presented by a Scot, and talks about many people who lived and worked in Scotland. I know much of modern geology has it’s roots in Scotland, but I’m sure there were many other important discoveries elsewhere that are glossed over in the programme. That said, it was produced by BBC Scotland.

The first programme deals with the age of the Earth, and how James Hutton came to realise the Earth was much older than was believed at the time. Iain visits the northwest coast, where one finds Lewisian Gneiss, and explains the mind-blowing fact that these visible rocks in Scotland are 2.7–3 billion years old. Which is about 2/3 the age of Planet Earth, a fact that I already knew. What I hadn’t really thought about, and wasn’t covered in the programme, is that this is a fifth of the age of the Universe!

Volcanism and continental drift were covered in the second part of the series. It explains how, through the study of fossilised trilobites, we know that Scotland was once part of what is now North America, and during the Caledonian orogeny it crashed into England. So Scotland really is a different country!

The third and final episode deals with glaciers and ice ages, and how we now know there have been 10 major glacial periods over the past million years, which is quite an amazing fact. Although I find it even more amazing that we can know this. Iain explains how James Croll, a janitor at Anderson College, developed his theory of ice ages based on the eccentric orbit of the Earth around the Sun, which was further developed by a Serbian who’s name they bear—the Milankovitch cycles. I had heard of the janitor Croll, but hadn’t realised that it was he who had come up with the basis of the Milankovitch cycles.

The series ends with projections of the next ice age, in about 40–50,000 years from now. But there is absolutely no mention of any human influence in future climate, and what this might do. Perhaps that was seen as too controversial, but I sincerely hope not. I suspect that it was just seen as too complicated, and would leave an unrelated unanswered question at the end of the series. But that is what life, and science in particular, is about—unanswered questions.