May 29, 2012
As a necessity, scientists of my generation often became expert draftsmen. Draftsmen are also known as draughtsmen, although beer is usually not involved. There were no computer applications for creating publication-quality data plots or diagrams, so everything was drawn by hand. In my case, the drawing often involved schematics of electronic circuits, which are somewhat more complicated than most drawings.
To do this drafting, I had a set of metal compasses, rulers, triangles, and circle templates; and I also had an exquisite set of pens (see photo). These pens were engineered to produce lines of precise width using India ink , a colloid of fine carbon soot in an aqueous vehicle. Lines made with India ink are very opaque, and they are easily reproduced.
Since India ink is made from carbon particles, these form a percolation network of low conductivity when the ink dries. Thus, India ink allows attachment of wires to measurement specimens when a highly conductive attachment is not required. It is especially useful in high voltage circuitry to allow a very high resistance ground return for components.
Octopus ink has had been used as a plot thickener in cartoons, but in antiquity it was actually used as an ink. The color, sepia (color code #5E2612), is associated with the ink of one order of cephalopods, the cuttlefish, which was harvested for ink.
Ink is nearly ubiquitous among cephalopods, so a natural question would be when such an evolutionary adaptation got started, and whether ancient cephalopod ink was different from modern ink. The problem here is that you need a specimen of primordial ink. A large international team of scientists has analyzed traces of ink from two ink sacks associated with fossils of 160-million-year-old giant cephalopods from the Jurassic period.[1-2] The fossils were discovered two years ago in England.
They found chemical traces of melanin, a common biological pigment for both plants and animals. The chemical structure was essentially identical to the melanin (specifically, eumelanin) found in the ink of modern cuttlefish.
The fossils with ink sacks were found in Christian Malford, Wiltshire, England, somewhat west of London, by Phillip Wilby of the British Geological Survey. One of the ink sacs is the only intact ink sac ever discovered.
Wilby sent samples to John Simon, a chemistry professor at the University of Virginia, and Japanese chemist Shoskue Ito, both of whom are experts in melanin. Simon and Ito assembled an international team with members from the United States, the United Kingdom, Japan and India, to chemically examine the fossil evidence in search of melanin, which was found.
That melanin, an organic compound, should survive after 160 million years, seems quite remarkable, since animal tissue decomposes quickly. Melanin, however, is more resistant to decomposition, since it's polymeric. Says Simon,
"Out of all of the organic pigments in living systems, melanin has the highest odds of being found in the fossil record... Though the other organic components of the cephalopod we studied are long gone, we've discovered through a variety of research methods that the melanin has remained in a condition that could be studied in exquisite detail."
The chemical composition of the trace evidence of melanin matched the melanin of modern cuttlefish ink. This affirms the possibility that the ink cloud defense mechanism of such creatures hasn't changed since the Jurassic. Says Simon, "The whole machinery apparently has been locked in time and passed down through succeeding generations of cuttlefish. It's a very optimized system for this animal and has been optimized for a long time."
A paper on this research has been published in the May 21, 2012, issue of the Proceedings of the National Academy of Sciences.
- Fariss Samarrai, "Cephalopod Ink from Jurassic Period Identical to Modern Cuttlefish Ink, U.Va. Study Shows," University of Virginia Press Release, May 21, 2012.
- Keely Glass, Shosuke Ito, Philip R. Wilby, Takayuki Sota, Atsushi Nakamura, C. Russell Bowers, Jakob Vinther, Suryendu Dutta, Roger Summons, Derek E. G. Briggs, Kazumasa Wakamatsu and John D. Simon, "Direct chemical evidence for eumelanin pigment from the Jurassic period," Proc. Natl. Acad. Sci., online before print May 21, 2012, doi: 10.1073/pnas.1118448109.
Permanent Link to this article
Linked Keywords: Scientist; baby boomer; drafter; draftsmen; draught beer; application software; computer application; scientific literature; data plot; diagram; drawing; schematic; electronic circuit; technical drawing; compass; ruler; triangle; circle; stencil; template; pen; India ink; colloid; carbon; soot; aqueous solution; vehicle; opacity; opaque; Staedtler Mars; percolation network; conductivity; high voltage; electrical ground; octopus; cephalopod ink; ink; plot; cartoon; ancient history; antiquity; sepia<; cephalopod; cuttlefish; Webster's Dictionary; Wikimedia Commons; evolutionary adaptation; fossil; Jurassic; England; chemical compound; chemical; melanin; biology; biological; plant; animal; eumelanin; Roland Mattern; Christian Malford; Wiltshire; South West England; England; London; British Geological Survey; John Simon; chemistry; University of Virginia; Japan; Japanese; chemist; United States; United Kingdom; India; organic compound; tissue; polymer; polymeric; Proceedings of the National Academy of Sciences.
Latest Books by Dev Gualtieri
Thanks to Cory Doctorow of BoingBoing for his favorable review of Secret Codes!
Blog Article Directory on a Single Page
- Soybean Graphene - March 23, 2017
- Income Inequality and Geometrical Frustration - March 20, 2017
- Wireless Power - March 16, 2017
- Trilobite Sex - March 13, 2017
- Freezing, Outside-In - March 9, 2017
- Ammonia Synthesis - March 6, 2017
- High Altitude Radiation - March 2, 2017
- C.N. Yang - February 27, 2017
- VOC Detection with Nanocrystals - February 23, 2017
- Molecular Fountains - February 20, 2017
- Jet Lag - February 16, 2017
- Highly Flexible Conductors - February 13, 2017
- Graphene Friction - February 9, 2017
- Dynamic Range - February 6, 2017
- Robert Boyle's To-Do List for Science - February 2, 2017
- Nanowire Ink - January 30, 2017
- Random Triangles - January 26, 2017
- Torricelli's law - January 23, 2017
- Magnetic Memory - January 19, 2017
- Graphene Putty - January 16, 2017
- Seahorse Genome - January 12, 2017
- Infinite c - January 9, 2017
- 150 Years of Transatlantic Telegraphy - January 5, 2017
- Cold Work on the Nanoscale - January 2, 2017
- Holidays 2016 - December 22, 2016
- Ballistics - December 19, 2016
- Salted Frogs - December 15, 2016
- Negative Thermal Expansion - December 12, 2016
- Verbal Cues and Stereotypes - December 8, 2016
- Capacitance Sensing - December 5, 2016
- Gallium Nitride Tribology - December 1, 2016
- Lunar Origin - November 27, 2016
- Pumpkin Propagation - November 24, 2016
- Math Anxiety - November 21, 2016
- Borophene - November 17, 2016
- Forced Innovation - November 14, 2016
- Combating Glare - November 10, 2016
- Solar Tilt and Planet Nine - November 7, 2016
- The Proton Size Problem - November 3, 2016
- Coffee Acoustics and Espresso Foam - October 31, 2016
- SnIP - An Inorganic Double Helix - October 27, 2016
- Seymour Papert (1928-2016) - October 24, 2016
- Mapping the Milky Way - October 20, 2016
- Electromagnetic Shielding - October 17, 2016
- The Lunacy of the Cows - October 13, 2016
- Random Coprimes and Pi - October 10, 2016
- James Cronin (1931-2016) - October 6, 2016
- The Ubiquitous Helix - October 3, 2016
- The Five-Second Rule - September 29, 2016
- Resistor Networks - September 26, 2016
- Brown Dwarfs - September 22, 2016
- Intrusion Rheology - September 19, 2016
- Falsifiability - September 15, 2016
- Fifth Force - September 12, 2016
- Renal Crystal Growth - September 8, 2016
- The Normality of Pi - September 5, 2016
- Metering Electrical Power - September 1, 2016
Deep Archive 2006-2008