Monday, 24 August 2009

Fossil squid ink story has whiskers

After 150m years as a fossil, Belemnotheutis antiquus takes up its pen (Simon de Bruxelles, The Times, August 19, 2009) is one of many "fossil squid ink" stories in the papers recently: the nice tale of a Jurassic belemnite fossil found in Wiltshire whose ink was so well preserved that it could be reconstituted and used for a drawing.

But ... this story rang distinct bells from my geology undergrad days, so I backtracked with Google Books.

One may thus draw pictures or write letters with squid "ink" and a squid "pen." Most remarkable of all, this is even possible with the ink and pen of fossil squids which lived millions of years ago.
- Bulletin of the Charleston Museum (1907)

The ink is not readily decomposed; onthe contrary it is occasionally found fossil in the rocks along with the remains of the animal which produced it. So well has it been preserved that in one celebrated instance a naturalist drew the portrait of a fossil squid with the sepia derived from its fossil, but not fossilized ink-bag.
- p363, The standard natural history, Volume 1, John Sterling Kingsley, Friedrich von Hellwald, Elliott Coues, 1884

It was discovered by Dr Buckland that in many specimens of fossil cephalopods, called scientifically Geoteuthis, i.e. Earth Squid, the ink-bag remained in the animal untouched by its long sojourn within the earth, and even retaining its quality of rapid mixture with water. A drawing was actually made by Sir F. Chantrey, with a portion of "sepia" taken from a fossil species, and the substance proved to be such excellent quality that an artist, to whom the sketch was shown, was desirous of learning the name of the colourman who prepared the tint.
- The illustrated natural history, Volume 3, John George Wood, 1863.

This tracks it down to the original account: see Dr Buckland's Bridgewater Treatise, The Monthly Review, Volume 3, 1836, for Buckland's report of the experiment, which was conducted in 1826. He probably got the idea from Elizabeth Philpot - a weathy Lyme Regis fossil collector who befriended the young Mary Anning - who also used the fossil sepia for drawings (see The Dragon Seekers: How an Extraordinary Circle of Fossilists Discovered the Dinosaurs and Paved the Way for Darwin, Christopher McGowan, Da Capo Press, 2002, ISBN 073820673).

A similar drawing, of the head of an ichthyosaur, was done by Henry De la Beche in 1834. See below: it's even captioned "Painted with fossil sepia".

Click to enlarge: image by "Cetae", Photobucket

So, the "sepia drawing" angle on the current news story is less radical than it appears. It's still interesting and a nice homage to the roots of modern palaeontology, but it's a pity that these precursors aren't credited. I've no idea if they were in the original BGS press release.

See The Fossil Treasure Hunt for the real story: the interesting rediscovery near Christian Malford, Wiltshire, of a deposit of fossiliferous clays, where conditions gave rise to remarkable preservation of soft tissue detail. 1 The so-called "Christian Malford Squid Bed" was discovered in the 1840s during the excavation of borrow pits dug for gravel during the construction of the Great Western Railway, and subsequently lost when the pits became flooded. See "Preserving the unpreservable: a lost world rediscovered at Christian Malford", UK, Philip R. Wilby, Keith Duff, Kevin Page & Susan Martin, Geology Today, Volume 24 Issue 3, Pages 95 - 98, Published Online: 6 May 2008.

PS: the fossil sepia drawing meme even turns up in HG Wells' 1895 The Time Machine:

In the universal decay this volatile substance [camphor] had chanced to survive, perhaps through many thousands of centuries. It reminded me of a sepia painting I had once seen done from the ink of a fossil Belemnite that must have perished and become fossilized millions of years ago.
- Chapter 8 (in which the Traveller explores the Palace of Green Porcelain) - spotting credit to Phil, forum.

Nor is this the only literary reference:

And the sweet milk of the heart's fountain,
Choked and crushed by a heavy mountain,
All curdled, and hardened, and blackened, doth shrink
Into the fossil sepia's ink.
- Geraldine, Martin Farquhar Tupper, 1838

This amazingly mixed metaphor of fossilisation, referring to the effect of jealousy, is discussed here in The Living Age. Geraldine is Tupper's continuation/sequel to Coleridge's unfinished poem Christabel.

1. NB: soft tissue detail - a number of creationist sites are enthusing about this find in the mistaken belief that the soft tissues themselves are preserved (implying the fossils to be recent). They're not; their structure is preserved, replaced by mineral - calcium phosphate. At least some of the mechanism for the surprising preservation in three dimensions of the solidified liquid content of the soft ink sac is known: check out the work of Larisa Doguzhaeva et al. It appears that the melanin in cephalopod ink rapidly reacts with water to form a solid under neutral or acidic conditions. See Oldest use of ink.

Addendum I knew the De La Beche ichthyosaur painting reminded me of something. It just surfaced: Salvador Dali's "Sleep".

- Ray


  1. You have to be fascinated by this compound, melanin. For openers, as you know, it makes black people's skin black, apparently related to the activity of the MC1R gene. To think that so much history was dependent on the activity of this gene in a given person. Mark Twain (in Pudd'nhead Wilson) would have been amazed.

  2. Yep. Social history apart, it has some very interesting properties: very stable polymer (since its job is to be UV-proof) which goes some way to explaining its persistence in fossils. But until skimming the Wikipedia article, I didn't know about its neurological role (why blue-eyed white cats are deaf), melanin-nicotine affinity, or radiotrophic fungi.