Showing posts with label fossils. Show all posts
Showing posts with label fossils. Show all posts

Wednesday, May 29, 2019

We want to go next

I was once a Geologist. The trick with geology is time. Imagine that if, every year, a stream were to cut a groove 1 millimetre in the ground. In two years the groove would be 2 mm deep and in 10 years it would be a centimetre deep. If the stream were to follow the same line for a million years the groove would be a kilometre deep. Just for my mum make it a sixteenth of an inch a year and the valley would be nearly a mile deep.

Now the earth is about four and a half billion years old. Just in case you're never sure what a billion is nowadays that would be 4,500,000,000 years. Obviously it's not possible but if our 1 mm a year stream flowed, non stop, in the same place, from the beginning, the groove would be 4,500 kilometres deep or about 500 times as deep as Mount Everest is high.

When I studied geology I found out about graptolites, brachiopods, lamellibranchs, belemnites and all sorts of other fossils large and small. I particularly approved of trilobites. I thought they looked cute. The first trilobites turned up some 520 million years ago and died out at the end of the Permian or about 250 million years. So the lifespan of all the different sorts of trilobites was 270,000,000 years.

There were a bunch of people before Homo Sapiens but the first Sapiens turned up in what is now Africa about 200,000 years ago. So trilobites lasted 1,350 times as long as people have existed so far. Stromatolites, by the way, make trilobites look like youngsters. They've been on Earth for 3,500,000,000 years and if you're not impressed by things you can't beat with a stick then jellyfish are around 500 million years old and elephant sharks are maybe 400 million years.

We've just had a couple of rounds of elections in Spain. The cambio de cromos, the dealing, has only just started in several areas. In Madrid the stupid internal wrangling of left wing politicians means that the conservative Partido Popular will probably get the leadership of the City Council. They can't do it alone though. In fact the PP governed Madrid, without break, from 1991 to 2015 and this time round they got their worst result ever. Nonetheless, with partners, they can govern. One of those partners is Vox, the fathead right wingers who have won their first representation at local, regional and national level this year. The outgoing mayor of Madrid is called Manuela Carmena. She actually polled the most votes in the elections but with all the permutations possible she can't pull together enough coalition votes to stay in office. Carmena put in place a scheme called Madrid Central. It's a programme to clean up the city environment. Bike lanes, pedestrianisation, not letting in the polluting vehicles etc. In the first month there was a 38% drop in Nitrogen Dioxide, 15% drop in Carbon Dioxide in Madrid with traffic flow down by 24%. And what does the potential new PP mayor say? - he will go back to less strict restrictions based on priority for residents and that he will concentrate on the problems that matter most to Madrileños such as clean streets and conservation. The Vox man said "starting tomorrow Madrid Central is over".

Those trilobites survived at least one mass extinction event, maybe two, before the one at the end of the Permian got them. There are various theories about the extinction from massive volcanic activity to a surge in microbe numbers but whatever it was it caused a destabilisation of the atmosphere and so the climate. Apparently after the Permian one it only took a couple of million years for the planet to bounce back though. To re-establish some sort of normality.

The general consensus is that there have been five big extinctions so far: late Devonian, 375 million years ago, 75% of species lost, end Permian, 251 million years ago, 96% of species lost, end Triassic, 200 million years ago, 80% of species lost, end Cretaceous, 66 million years ago, 76% of all species lost. I've heard that some plastics can take 1,000 years to decompose. As I said the trick with geology, the trick with the planet, is time. Currently humans, as a species, are a tiny blip in geological time. If fossil fuel type pollution started with the Industrial Revolution then people have been affecting the atmosphere for about 290 years or 0.145% of our time on Earth. It does seem a bit stupid though to purposely speed up the dash towards that next extinction event.