Pumice is interesting stuff. For one thing, it’s light. Really light. It has such a low density that it can and does float in water. It’s also very English muffin-like in its myriad nooks and crannies. These and some other key properties have had some who study the origins of life (here and on other planets) thinking hard about pumice as a possible starting place for life.
In the September issue of the journal Astrobiology, Martin D. Brasier and coauthors lay out their case for pumice (Brasier 2011).
And I think pumice has a strong case indeed. But what really intrigues me is that Brasier, et al. seem to think they’re on to something… novel.
The notion of tiny rock compartments acting as reaction vessels for the synthesis and development of early organic molecules is not, of course, a new idea (see Nisbet, 1985). Others have argued for the potential of micropores within feldspar and zeolite minerals (Parsons et al., 1998; Smith 1998; Smith et al., 1999). The potential of such fabrics for RNA synthesis has lately gained support from computer modeling (Branciamore et al., 2009). But the potential of pumice for the emergence of early life—plus the diagenetic mineral suites to which pumice can play host—has not received attention. Below, we therefore explore the possibility that extensive rafts of pumice were positioned for hundreds—possibly thousands—of years at the interface of the early ocean-atmosphere-lithosphere system, concentrating metals, phosphates, catalysts, and organic polymers. We explore whether such deposits could have provided a remarkable setting for the emergence of the first life on Earth
Interesting stuff. But there’s a slight problem. Pumice as the location of the origin of life has “received attention”. Curtis Ebbesmeyer coauthored (with Akira Okubo) a letter and submitted it to Nature back in 1993 on exactly this subject, entitled “Origin of Life in Floating Pumice”. Nature did not accept the letter for publication, suggesting further work to bolster their case. Ebbesmeyer published the submitted letter in the journal Oceanography a few years later as part of a tribute issue to Akira (Ebbesmeyer 1999).
I first came across Ebbesmeyer’s pumice hypothesis ten years later, in the book Ebesmeyer coauthored with Eric Scigliano recounting Ebbesmeyer’s oceanographic career entitled Flotsametrics. (Ebbesmeyer achieved notoriety by using Nike footwear and rubber duck bath toys lost at sea to track ocean currents.)
To be clear, I don’t think that Brasier et al. have done anything untoward. It’s not as though Ebbesmeyer and Akira Okubo actually published their paper in a conventional manner. And had I not had Ebbesmeyer’s book recommended to me, I wouldn’t have any idea that someone got there first.
I think the pumice idea is a fascinating one, and Brasier et al. seem to have written the kind of paper that Nature suggested Ebbesmeyer and Akira resubmit with. I hope if any negative attention comes out of this that it will at least spark a greater interest in this fascinating candidate for the first place life called home.
- Brasier, M.D., et al. (2011): Pumice as a Remarkable Substrate for the Origin of Life. Astrobiology, 11(7), 725-735, doi:10.1089/ast.2010.0546.
- Ebbesmeyer, C. (1999): Pumice and Mines Afloat on the Sea. Oceanography, 12, 1, 17-21.
- Ebbesmeyer, C., and E. Scigliano (2009): Flotsametrics and the Floating World: How One Man’s Obsession with Runaway Sneakers and Rubber Ducks Revolutionized Ocean Science. Smithsonian, ISBN: 0061558419.