Tym the Trilobite: How I died and got preserved

Used with permission

Well, in spite of the predators, all in all life was pretty good. As long as you kept on your toes and kept your wits about you a trilobite’s life was not a bad one.

But, then ‘it’ happened – I bought the farm, bit the bullet; the big ‘D’ – death! …and it wasn’t pretty.

It was a bit of a catastrophic event actually and there wasn’t much I could do about it. I’ve already told you that the natural world was pretty hectic back then, what with meteor strikes, earthquakes, tidal waves and the like. There was never a dull moment.

Well, just my luck, there I was pottering around the sea floor and the next thing I know all these tiny particles came raining down through the water.

Oh no! I knew what this was - ash from one of the volcanoes along the coast. I’ve seen it before and managed to dodge it.

But this time I was in the wrong place at the wrong time, along with lots of my mates. Well, I started scurrying away as fast as I could, but it kept on raining down ash and it was getting thicker and thicker on the sea floor.

Finally my poor little legs just couldn’t keep up. It was horrible, I was buried alive by a thick blanket of volcanic ash and suffocated to death! It would be exactly like a human being buried by snow avalanche.

The only good thing about my horrible death is that it happened so quickly it did allow me to get a sort of second life as a fossil. Not that you can do much as a fossil except observe the millions of years go by.

Now, being buried by a load of sediment, whether it is mud or volcanic ash, doesn’t make you a fossil on its own. The sediment then has to get turned into rock and my body parts needed to be delicately invaded and preserved by a rock forming mineral.

In my case that mineral was silica. It’s a pretty common mineral in rocks and it’s good at preserving things. As my calcite skeleton started to dissolve, in came sneaky silica, carried by mineral rich groundwater percolating though the sediment.

The silica precipitated out of the ground water, and took over in place of my slowly dissolving calcite skeleton. It perfectly replicated the parts of me that were dissolving away. Then as the water got squeezed out of the sediment turning it into rock, the silica crystallized and ta-da... I was turned to stone, fossilized and perfectly preserved for all time!

So there you go, now you know the whole of my life story from beginning to end. If you’ve enjoyed reading it and want to find out more about fossils, then I would strongly recommend the book Trilobite! Eyewitness to evolution by Richard Fortey, and if you want to find out more about fossilization and rocks then Teach Yourself Geology by David Rothery is a good place to start. 

You can also go to the video gallery and see Richard Fortey and Janet Sumner talking about their favourite fossils – and. yes you’ve guessed it, they’re both Trilobites!

Inteview with the trilobite

Acknowledgements

Tym's story was as told to Janet Sumner.

Janet would like to thank Richard Fortey for casting his very experienced eye overTym's blog and checking that no scientific ‘howlers’ had crept into the story.

If you’ve enjoyed the ‘Tym the Trilobite’ blog, why add your story, below, of what it was like to live as your favourite fossil?