Murex, chaos theory of a shellfish

   I found a cool snail shell today.

   Look at it, look at the spikes ! It’s pretty great, right ?

   Can you believe Nature makes these kind of things ? 

   That’s a reflection that Antoni Gaudí had, by the way. 

   He was a deeply pious man, and wanted to honor God in his architecture. But his reasoning went as follows : God created Nature, and Nature is not only pretty flowers.

Nature is full of crazy shapes and geometrical forms like fractals, helicoids & hyperboloids.

Just look at this shell !

   If I wanted to write about it, it’s not only because I love Gaudí, but because of something else. This shell inspired me a few reflections I’d like to share with you.

   This is the shell of a marine animal called Bolinus brandaris. It is part of a wider family of Gastropods called Muricidae.

   Historically it has been called Murex. And today its common name still is Murex, spiny dye-murex.

   You find it primarily in the Mediterranean Sea but also on some Atlantic shores of North Africa.

   What you have to know about this snail is that it once was one of the most luxurious commodities in the Mediterranean World. They were used as dyestuff. 

Murex brandaris & its cousins produce a molecule called 6,6’-Dibromoindigo - C16H8Br2N2O2 - that you can use, by crushing them alive, to dye clothes and create pigment. 

   They create a very specific shade of deep, hearty purple, tending towards the red. It was called the « Tyrian Purple », in reference to the Phoenician city of Tyre, where this technique originated.

   So, this fact has been known since at least the Phoenician, and they settled here, close to where I found this shell, around the 7th to 6th century BC. 

   We know that because they constructed a fortress - Migdal - on an Island which would later be called Mogador, located off the coast of present day Morocco. 

   Would you look at the map, we’re quite far away from the Mediterranean, let alone the homeland of the Phoenicians in the Levant. This was not the only production site of Murex dye, but it was the furthest out there.

   The Amazigh King Juba II and then the Romans took over the infrastructures a few centuries later and would develop it into a larger scale industry.

   And to have created an industry that far away for something so… unnecessary (?) really tickles my brain. 

   Because of course, we know necessity is a social thing. 

   Thanks of its rarity, and the difficulty of accessing this shellfish, and even the process (estimations made in the 1900’s showed you needed about 12000 snails to create 1,4g of pigment), this specific dye became synonymous with luxury, with importance.

   That’s why, starting in Antiquity and well into Medieval times, this shade of Red-Purple became the color of the Emperors, of which the Papacy inherited, and by extension the clergy. 

   In the clergy, the highest members of the hierarchy have their whole cape dyed in Tyrian Purple, while lower ranks have half of it, or only the scarf, etc. 

   By capillarity, this hierarchical symbolism of Purple got transmitted into other spheres, most notably becoming a symbol of Monarchies, and more generally of high social status. 

   Now I’d like to make a small parenthesis and talk about global warming. More precisely effects that rising of temperatures have on populations.

   So there is this belief that a few degrees don’t have an impact on humans, because « common sense » says that if you go out on your day to day basis, you don’t really feel the difference of a couple degrees. 

   You could write a book about this, I should patent the idea, but I’ll keep it to a couple sentences for the sake of what I want to talk about today.

   Humans created tools to cope, to a certain extent, with variations of temperature. We have clothes, we have walls & carpets, we have fans, we have AC and petroleum to fuel the electric generators to provide energy for our AC.

   Other wildlife hasn’t. 

   Humans have however built their infrastructures and own lifestyles around the exploitation of this very wildlife that is influenced greatly by a little difference in global temperature.

   Case and point : Shellfish !

   This has been shown that the rise of like, half a degree in ocean water on the North American East coast, while barely perceptible by humans, had the whole population of lobsters moving North of about 500km in about a decade to reach the cooler waters that they were used to.

   The populations of lobsters apparently stayed relatively stable, they just moved North.

   The thing is, you can easily imagine that, because of inertia, borders, immovable infrastructure and slowly moving mental structures, this migration has a great impact on the lobster industry and all the fishermen of the American East coast, and by implication, huge economic & social impacts. Half a degree, remember.

   Another small parenthesis, I’d like to talk about the history of Mogador. It all comes to a point, I promise.

   Mogador was renamed Essaouira at the independence in 1956. You might know it, it’s one of the most visited cities in Modern Morocco. 

There is a lot of wind there, so there is kitesurfing ; it’s really quite beautiful, so there’s tourism ; there’s craftsmanship, it’s a fishing port so there’s good fish to eat, all good.

   In conjunction with the rise of tourism, they also have a developed nice music festivals in the last couple of decades. There’s a Jazz festival, an Andalusian music festival, and the most famous is probably their Gnaoua music festival.

Gnaoua is a musical style that really developed in this region around Essaouira, so that’s very fitting, but that’s no coincidence.

   Gnaoua is a musical blend between Moroccan and Subsaharan Africa’s musical traditions, that really grew in Essaouira because of the slave trade.

   Oh, I guess we have to speak about the slave trade.

   Yes, Mogador developed into a city and a harbor after the departure of the Romans, one of the largest harbors in the North African Atlantic coast, and thanks to it’s proximity with Caravan routes from Timbuktu or Dakar, it became instrumental to the slave trade from the 15th to the 19th century. Large harbor, lots of people there, economic opportunities ! 

   The city grew larger, people came in, the culture flourished, and here we are, a few centuries later.

   People have been born in Essaouira, people have died there. People made war, people made love. People fought, people danced. They grew an attachment to the place, they became part of it, it became part of them.

   What all this rambles about the Phoenicians, Antique dying techniques & American lobsters make me wonder is, how much of the long history influences the present, and how much of it is due to randomness.

   These waters could have been half a degree too cold or too warm for these snails to survive here, or the Phoenicians could have thought that venturing out of the Mediterranean was too far for them, and Mogador wouldn’t have been placed here. Or maybe it would have been, maybe the harbor is just so well located that the local Amazigh tribes would have implanted their harbor coincidentally where the Phoenicians and then Romans had not left the infrastructures for it centuries before. I guess we’ll never know.

   And what if the pigment you get from this snails had been neon-green, or orange pastel ? Can you imagine the Pope in a neon-green robe ? How different the cultural significance of colors in the Western World would have been.

   Randomly, purple became royal & important. It could randomly have been otherwise.

   I’m often wondering how much could randomly have been different. 

   That’s a cool shell, isn't it ?

Etienne, February 12026