1988 | Source: Omni, 11 (1, pp. 92-170) | Author: E. Regis and T. Dworetzky
Around the turn of the century Leduc had been studying osmosis, the phenomenon by which molecules move through a membrane from a highly concentrated solution to one that is less concentrated. When living cells osmose, or draw, material through their membranes, they are able to receive nourishment and pass out waste.
FIGURE 2 CaCl2 (s)/Na3PO4 (aq) system: from top to bottom, 10:30 a.m., 10:53 a.m. and 11:05 a.m.
While studying the phenomenon, Leduc found that certain types of inorganic material, when placed in solution, actually grep into structures surrounded by osmotic membranes. They bore an amazing resemblance to the structures of life. Once the membranes were formed, in fact, the inanimate substances began paging molecules back and forth much as if Theky were alive. These growths, Leduc reported in 1911, "put forth bud and stem and root and branch and leaf and fruit." Indeed, he declared, his structures looked like plants right down to the microscopic level. They reproduced, went through a period of youth (in which they moved like animals), and then grew old and died. "We are at a loss," Leduc said, "to define any line of separation between these mineral forms and those of organic life." In the end the scientists of Leduc's day — including Louis Pasteur— lumped the behavior of osmotic growths with the disproved notion of spontaneous generation. They dismissed the phenomenon as unimportant, and it might have stayed buried forever if not for Zeleny and his crew.
Convinced that Leduc's findings revealed something valuable about the essence of life — its organization — Zeleny set out to reproduce some of these experiments himself. Following the models described by Leduc so many decades before, he took broken fragments of solid calcium chloride and manganese chloride and dissolved them in solutions of inorganic salt. As he sat watching his "primordial soup" over a period of days, he saw a variety of A-life forms sprout. Some of these entities resembled plants, while others had the traits of fish or worms.
According to Zeleny, in fact, depending upon the exact substances used, his osmotic growths included stems, leaves, flowers, buds, fins, amoebas, and worms. Many of his creations even had what looked like cilia, the tiny hair cells used to help a whole range of animal species transport nutrients and wastes from one place to the next. What's more, Zeleny's smooth, lifelike structures seemed to live and breathe. Like living cells, he says, his crystalline creatures transport matter across their membranes, absorbing the components they need for nutrition and expelling the rest as waste. They also repair themselves by growing new membranous cells to replace those that rupture and "die." And they exhibit the uncannily lifelike ability to reproduce by spawning buds. Finally, if a crystal grows out of the water into air, ils entire structure changes; that is, it evolves. But perhaps most intriguing to Zeleny and his collaborators, George Klir of the State University of New York at Binghamton, and Kevin Hufford of Broome Community College in Binghamton, is these creations' capacity for "autopoiesis." Like living cells and organisms, they are literally able to orchestrate a continual turnover of their parts. 'A living cell," Zeleny explains, "exists by virtue of a complex set of processes that synthesize proteins, enzymes, lipids, and more. These processes renew the individual elements of the cell thousands of times during its lifetime - yet throughout this turnover, the cell maintains its distinctiveness and autonomy."
This lasting unity and wholeness in the midst of continual turnover defines Zeleny 's cre- ations as well. Are Ihese structures alive'? "There is no sharp division, no precise limit where inanimate nature ends and life, or animate nature, begins," Zeleny says. 'What we can say is that there seem to be major organizational themes: The shells, leaves, stems, and protuberant flowers of nature are apparently not just properties of organic living matter but are old and more basic." It appears that any matter, under certain conditions, can take on the characteristics of biological life.
The philosophical questions emerging from Cairns-Smith's and Zeleny's work are profound: If inanimate matter can organize itself in biological form, is it innately differ-ent from organic life? Will organic and inorganic creatures ever merge, making a being that combines attributes of both?
And if we view life as a system of organization as opposed to a collection of "stuff," then might we begin to unearth the living in places we never dreamed of? Finally, how much of what we now see in the fossil record were actually osmotic growths and other forms of nonbiological life?
To unravel some of these mysteries, Zeleny and colleagues are currently modeling the patterns of osmotic growth on the computer screen. Over the short term they hope to dissect, for instance, the process that makes the growths shoot up in a vertical direction; the means by which the growths slow, thicken, and eventually stop; and the mechanism that controls a growth's ultimate decay. If, as they hope, their work leads to a full understanding of the life cycle of the osmotic growth, they may eventually be able to alter these forms at will.