Every Second Counts

25Nov
Every Second Counts
Geological time from http://www.memrise.com/

Guest post by Eleanor Ainscoe

Everyone’s heard the story. If you condense the entire history of the Earth into a 24 hour day, life on land starts at about 10pm, dinosaurs which, so far as I was concerned as a kid, were almost back at the beginning of time, don’t appear until almost 11pm. And hominids? 23:58:43. It’s an open and shut case. A guaranteed way to make you feel small. Could you ask for any clearer evidence that we don’t matter in the Earth’s history?

Apparently not everyone agrees. The theme of our seminar was “Critical Moments in Earth’s History”. It all started conventionally: the Earth Scientists suggested the formation of the first continental crust and breakup of Pangea, the Palaeontologists threw in the Cambrian Explosion and so on. But then people from the other DTP streams started making themselves heard. The industrial revolution, development of agriculture, the Anthropocene. The development of agriculture?! I could have sat in that warm, stuffy room until Christmas and not come up with the development of agriculture.

If we say the industrial revolution started in about 1760, 254 years ago, how close to midnight would it appear in our 24 hour Earth clock? About five microseconds (I get 4.8 x 10-6 s). That’s tiny. Even trying to think of a real-life thing to relate 5 microseconds to is difficult. Blinking takes about 400ms – five orders of magnitude too slow. A bee flapping its wings takes about 3-5 milliseconds – three orders of magnitude too slow.  You can’t do a lot in five microseconds, light can travel about a mile I don’t think there is anything in normal life that we can compare it to.

Anyway you get the idea, in terms of chunks on the timeline anything to do with humans is pretty insignificant. But all the same, I don’t think you’d catch a dodo saying that the rise of hominids is insignificant. I don’t think you’ll catch a dodo at all to be honest but you know what I mean. It’s all about context and perspective. In terms of what’s important to society and individual lives the industrial revolution was a pretty big deal and the following ramping up of pollution and greenhouse gas emissions is an even bigger deal for the ecosystem.

Atmospheric CO2 passed 400ppm for the first time in at least 800, 000 years, nuclear testing has altered isotope concentrations and ratios worldwide, the species that we’re driving to extinction won’t come back. In fact, some people say that we’ve made such a big impact that we’ll leave a lasting, noticeable imprint on the geological record. That’s what the Anthropocene thing earlier was about.

So yes, the Late Heavy Bombardment might have been the bigger event in the 24 hour long view but for us, these last few milliseconds have been pretty critical.

Eleanor Ainscoe is a research student in the 2014 cohort.