A sea urchin in my garden!

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I was digging in my garden yesterday and I saw something that looked like a curled up grub sitting on the soil. I picked it up and realised it was once alive,  but hasn’t for quite some time.

Here’s an end on view, showing why I thought it was a grub hunched over itself. Note the ridged appearance.

It was a fossil echinoid, or sea-urchin to use its every day name. It is quite small (1 cm across) and quite lovely. I was quite excited as I never expected to find a fossil in my garden. The underlying geology is recent (post-Cretaceous) sediments but my garden sits on an old Thames river terrace. This is mostly gravel and you don’t get fossils in gravel. Or so I thought.

I was also excited as I’d just got a new camera with a macro setting for close-up pictures. I can take a hint from coincidence, so here we are.

A view of its underside. Note how the ridges we saw above curve down under. Towards the bottom of the image you can see little dots in an areas between two ridges. These are pore-pairs and are where the echinoid’s tube-feet were attached.  If you look carefully, you can just about make out a five-fold symmetry that is very distinctive of this group of animals (echinoids) and is rather more obvious in starfish.

Here’s a view of the other (top) side.

Again there is a ragged lump in the middle, which is a clue to how this fossil ended up in my garden. Echinoderms have a strong shell, but the middle of the top and bottom surfaces is open or covered by fragile bits of shell. This is so it can get food in and then out again. These more fragile bits are rarely preserved. This fossil is made of flint which will have replaced or infilled the actual shell. The impression of the shell will have been within a larger piece of flint – the raggedy bits are where the large piece broke up, revealing the fossil within.

Picture yourself in the Cretaceous. There’s a warm sea, which is shallow but weirdly there is no land in sight. A baby sea-urchin is burrowing in the chalk mud living a full and happy life – the white mud it frolics in suits it just fine. Eventually death comes and our hero ends up in a mass grave (that nice white mud is actually billions of algae corpses, or coccolithophores). More corpses lie on top, and things warm up a little. Silica and water zips around and our hero ends up entombed in flint. Fade to black.

A new scene, a chalk outcrop in a world that looks much like ours, only there are no people. A lump of flint is eroded out of the chalk and slides downhill. Below lies a river that will one day be called the Thames.

Now the Thames is flowing hard. It’s hard bouncing and banging along the river bottom and something has to give. With a muffled clonk that no-one hears, the flint pebble fractures and something beautiful appears  – our hero. It’s now exposed to the jostling and banging, but soon reaches quiet water and is covered by more flint.

We reach the present day. The gravel terrace has been mixed up by frost-thaw action during periods of near Arctic conditions (ice ages) and the top layer is now mixed in with dead plant matter to form soil.  A spade turns the soil  and our hero finally reaches the surface again, where someone can find him and tell his story.

What geology did to me #4 – scientific thinking

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I work in IT, computers, geeky stuff. Having been a programmer I now manage a team of them, building new systems and supporting old ones. Having a science PhD is quite a common background in my line of business. Not the best use of my scientific training perhaps, but at least I don’t work for an investment bank.

Computer programs are sets of instructions written by humans, who get things wrong. The instructions are then followed by computers, which are stupid. Throw into the mix the fact that the people who pay for software often don’t understand IT and sometimes don’t really know what they want and you get an explanation for the high cost of the average IT project. [Or so I’ve heard, obviously my current and any future employers are exceptions from this depressing picture *cough*]. A big part of the cost of software is testing it to remove bugs. Removing them all is nearly impossible (you’ve used software, so you know what I mean).  Simply removing the embarrassing ones is hard enough. Many bugs are where the person writing the code has made an obvious mistake. These are easy to diagnose and fix.

The bugs that the manager in me most fears (and the geek in me quite enjoys) are the hard ones. The ones where the fault is intermittent, strange and where you don’t even know where the fault lies.

In the old days, computers were big humming boxes in the corner of the room. There was only one set of code to go wrong. This old mainframe code is fantastically successful and is still running in many companies. If you perform a financial transaction it is likely that some of the code involved was written in the 1960s or 70s by a quietly spoken man with a beard and flared trousers.

Now life is more interesting. Imagine this web-page has gone wrong in some way. Where is the fault? It could be the blogging software, or the database software the blogging software uses, or the operating system of the server hosting this site. Or it could be a router, DNS server, piece of cable, piece of wire, internet cache or network accelerator anywhere between the server and your computer. Or it could be your browser, or your operating system, or you. Yes you! You might raise a bug saying this post should be more interesting: clearly nonsense, user error!

You take my point. Most of the applications my team supports are web-based. Often if a user raises an bug we don’t know where the problems lies. I work for a big company and our systems are much more complicated than my example.

Inexperienced developers when confronted by an urgent bug often dive into the code. They feel safe there, they feel like they are doing something. Wiser heads take a step back and start formulating hypotheses and collect data to falsify them. In order to fix a complex problem you must first understand it. This requires you to engage with a large and complicated situation, decide what you think is going on and then collect more information to see if you are right or not. A geological training is a good preparation for this.  We know that there are variety of ways of gathering more information: a literature search, mapping, thin-sections, microprobe, isotopic analysis and so on. Deciding between more logging, sniffing the network, finding out how many users the problems affects or getting details of a user’s desktop configuration is a very similar process.

With Geology, understanding something is the goal. When fixing a bug, this is only the first stage, but it is usually the hardest. If the problem is in your code, a fix may be easy, it may be hard but at least the solution is in your own hands. If you need a fix quickly, then there is always some dirty hack tactical enhancement available. If you are unlucky and the problem is in someone else’s code then having an explanation complete with evidence is vital. Getting someone else to take responsibility for ‘your’ problem is basically against human nature. The trick is to have compelling evidence and to use it to make your case clearly and concisely. Again, my geo soft skills come into play.

Just to close the conceptual loop, consider the ‘faster than light’ neutrino situation. The last I read the ‘impossible’ result has been traced back to a fault in a cable in a GPS device. Surely this is a case of scientists using the scientific method to find bugs in systems? To be fair though, I’ve never yet invoked Einstein’s theory of relativity to solve one of mine.

My most important teacher – John Dewey

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This is my contribution to the ‘most important teacher’ Accretionary Wedge.

I’ve had the privilege of learning from many excellent teachers. Choosing one single person to talk about is somewhat arbitrary. I’ve chosen someone who, of my teachers, is the most important figure in the wider world.

Professor John Frederick Dewey is an major figure in geology. He’s a Fellow of the Royal Society, a member of the US National Academy of Science and winner of numerous awards and accolades. He’s held professorships at prestigious universities both sides of the Atlantic and has taught over 40 PhD students and countless undergraduates. Most interestingly, he was there at the beginning. He’s part of the generation for whom plate tectonics was a fabulous novelty, a bolt from the blue that transformed the study of the earth in so many ways.

John made his career by being one of the first geologists to apply plate tectonic theory to specific mountain belts. This involves the impressive trick of linking field-based studies to high-level plate tectonic concepts (e.g. “closure of ancient ocean, then collision of oceanic island arc then closure of ancient ocean”). Throughout his career he’s covered pretty much every orogeny on the planet and many types of concept (orogenic collapse, transpression/transtension to name but two). To give a flavour of his depth of geographical coverage, the hat in the picture above was a Chinese Army one from a trip across Tibet and I’ve see him have a good natured debate over which is the best fish-restaurant in South America. He is currently based in California but his home-base as regards Geology is the West of Ireland, where he did his PhD research.

As you can see from the above, John is a bit of a showman. I know him  best from 5 years of Irish undergraduate field trips. Sitting in a wrecked bog-car to amuse the students is entirely in character, as is eating raw mussels, freshly ripped from the outcrop, to show how clean the Atlantic sea-water is. Every year in Ireland, he would allow an hour or so to make everyone play cricket, often on a road. Western Irish roads are often an arena of oddness (I was overtaken by a hearse once) but 40 young people in rain gear and one Fellow of the Royal Society knocking a ball around is still a rather unusual sight, even there.

What did I learn from him? Firstly, a love of tectonics and the grand intellectual game of understanding how mountains form. It’s exhilarating to hear him talk on this subject. Take my own research on Irish rocks (which he co-supervised). For John this is a tiny brick in a grand edifice, helping him correlate the geology of Ireland with that of Scotland to understand the Grampian orogeny. This is then a part of the grander picture of the closing of the Iapetus ocean, which formed the Caledonidian (British Isles, Greenland), Scandian (Norway) and Appalachian (US and Canada) orogenies. The short duration of the Grampian orogeny allows comparisons with New Guinea and contrasts with the Alps and Himalayas. To stand on a single Irish outcrop and link it into an intellectual scheme that spans and seeks to explain the entire world, this is real science.

Another, broader thing I learn from him is the importance of mastering the detail, but also lifting up your head to the broader things. To succeed in many professions you need to master the detail, to learn a craft and have specific skills. But to really get on you need to link this to a bigger picture. Detailed careful work is important, but maybe its worth spending less time on dotting every i and more time on telling a great story, making a splash and creating research that is seen to be interesting and important.

Information about left-handed geologists: results

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A week ago I asked you all to provide me with some data about left-handedness in Geologists. I was very pleased with the response and I thought it was about time to collate the results.

Twitter: a lot of you replied by Twitter. This was enormously helped by Chris Rowan lending a hand in spreading the word. He also captured it all in Storify.

These results are: 11 left, 17 right and 5 ambidextrous.

Blog comments and online form: Those of you who are non-tweeps (and one who is, who wasn’t double-counted) gave me information in the comments or on a Google form I set up.

These results are: 11 left, 11 right and 2 ambidextrous which added to Twitter data gives 39% left, 49% right and 12% ambidextrous. This is rather close to my guess of 40%. Too close perhaps?

Estimates of proportions: The chances of sampling bias on this data is rather high. Are left-handers more likely to click on a link with left-handed in the title? Of course we are, but this is impossible to quantify. Many of you provided another, perhaps more valuable form of data in estimates or counts of the number of left-handers in groups of geologists. Since you are all good scientists I’ll assume there is zero sampling bias on this data. The total sample size here is 205, of whom 43 are lefties (21%). No ambidextrous people mentioned.

Adding these two sets of data (adding ambidextrous and leftie together) gives a headline of 27% of Geologists are not right-handed.

Some of you gave percentages with no total. These were: 12.5-20%, 15-25% and “about a half”. Again this is in the same ball-park. I have two conclusions:

Social media is fantastic, especially with geologists involved.

Around a quarter of geologists are left-handed and they may be unusually ambidextrous too.

More research required, ideally of the rigorous sort, but there is enough data here to justify it. I’ll email my psychologist contact back…