Tuesday, April 9, 2013

The Moon and the Mysterious Nautilus

G. Tracy Mehan, III

Noted ecologist Daniel Botkin provides a remarkable description of a natural phenomenon which is also the title of his new book, The Moon In The Nautilus Shell: Discordant Harmonies Reconsidered. Botkin describes the chambered nautilus (Nautilus pompilius Linnaeus), one of “the humblest and most obscure creatures”, which dwells in the southwestern Pacific Ocean. It is “a cryptic creature with nocturnal habits, living in the depths of the ocean, as much as 1,000 feet below the surface, and rarely seen alive by human beings.” Its oldest fossil ancestors date back 420 million years.

The nautilus lives in the outermost chamber of its shell. As it grows it needs a larger protective shield, and the chambers grow in size, the shell “coiling into the convoluted shape of a logarithmic spiral, following a simple but elegant mathematical formula.”

Along the opening of the outer chamber of its shell, small deposits of calcium carbonate are laid down in groups of three to five, separated from the others by a ridge or “growth line.” On average there are 30 growth lines per chamber, one for each day in the lunar cycle, “suggesting that a new chamber is put down each lunar month and a new growth line each day. From this it can be inferred “that the chambered nautilus contains in its shell two clocks: one timed to the sun, the other to the moon.”

“Strangely, the number of growth lines per chamber has increased over time,” writes Dr. Botkin. Older fossil shells have only nine growth lines per chamber. Modern shells have thirty. This, in turn, suggests “that the lunar month has grown longer and that the moon used to revolve faster around Earth than it does now.” Ergo, “the moon must have been closer to Earth, since the closer a satellite is to a planet, the faster it must revolve to remain in orbit.” It would seem that the revolution of the moon 420 million years ago took only nine days. Since then there has been a loss of energy from friction of the tides, causing the moon to recede slowly as it continues to do.

This loss of energy from friction increased when the continents emerged about 600 million years ago. “Thus in the chambered nautilus, the solar system, the physical Earth, and life on Earth are linked,” Botkin writes.

An interesting question arises: if the moon’s orbit continues its drift, what might its impact be on inter-tidal life at some future point in time? As Heraclitus said, “All is flux.”

Professor Botkin sees in the image of the chambered nautilus a model for a new unity in which human beings can live and thrive within a wondrous, unsettling, and dynamic ecosystem. No longer should nature be characterized in terms of a “balance of nature” which assumes that nature, undisturbed by human beings, achieves a steady state or equilibrium, a kind of constancy in terms of maximum biomass and diversity. It is the deconstruction of this old view of nature which takes up most of the book.

The Moon In The Nautilus Shell is an expanded and updated version of Botkin’s 1990 landmark book Discordant Harmonies: A New Ecology for the 21st Century.In it he challenged the idea that nature maintains its equilibrium indefinitely as long as people just leave it alone -- since they can only have negative effects on it. Take the case of the Boundary Waters Canoe Area in northern Minnesota, a remarkable place which would meet most people’s conventional idea of wilderness. According to Dr Botkin it has, from the end of the last ice age until the time of European colonization, “passed from the ice and tundra to spruce and jack pine forest.” From there it shifted to paper birch and adler, and then back to spruce, jack pine and white pine driven by variable climate. Botkin asks: “Which of these forests represented the natural state?”

“If natural means simply before human intervention, then all these habitats could be claimed as natural, contrary to what people really mean and really want,” claims Botkin. “What people want in the Boundary Waters Canoe Area is a wilderness as seen by the voyageurs and a landscape that gives the feeling of being untouched by people.” Nothing wrong with that, but a choice must be made.

Botkin offers numerous case histories where failure to appreciate the role of change and disturbance led to bad management decisions such as the total suppression of fire in forests. This resulted, for instance, in the decline of the giant sequoia trees on the west coast of the United States. However, letting nature take its course, without any human intervention, can also be fatal as in the case of the elephant herd in Kenya’s Tsavo national park in which game managers ignored a population explosion, stood by and waited for “the attainment of a natural ecological climax.” That elephant population crashed and did not recover for years.

Another contributor to this conversation is Emma Marris, a writer for the science journal Nature and the author of Rambunctious Garden: Saving Nature in a Post-Wild World. She uses the metaphor of an unruly garden to illustrate the dynamic, changing nature of nature, and the predictably unpredictable role of human beings. “We are already running the whole Earth, whether we admit it or not,” asserts Marris. “But from the point of view of a geologist or paleo-ecologist, ecosystems are in a constant dance, as their components compete, react, evolve, migrate, and form new communities.”

It may be impossible to restore conditions, say, in an Australian sanctuary to 1770 by trapping and killing thousands of introduced rabbits. Yet, it might be possible to manage it for something achievable such as avoiding extinction of rare or endangered species. Humans have lived in Australia for 50,000 years. “Aborigines increased the amount of flammable plant material… This, combined with their fire-setting ways, may have changed the dominant species in many parts of the country,” she writes.

“A consequence of throwing out the ‘pristine wilderness’ ideal is that conservationists, and society at large, now have to formulate alternative goals for conservation,” says Marris. “In a nutshell, give up romantic notions of a stable Eden, be honest about goals and costs, keep land from mindless development, and try just about everything.”

Marris echoes Botkin who observes, “Nature in the twenty-first century will be a nature that we make; the question is the degree to which this molding will be intentional or unintentional, desirable or undesirable.” Botkin recognizes that abandoning the belief in the constancy of nature is very discomforting leaving us in “an extreme existential position.”

Environmental historian and Bancroft prize winner William Cronon wrote a challenging essay in 1995, “The Trouble with Wilderness; Or, Getting Back to the Wrong Nature”, in which he claimed it was time “to rethink wilderness.”

Wilderness is “profoundly a human creation” and a “flight from history that is very nearly the core of wilderness represents the false hope of an escape from responsibility, the illusion that we can somehow wipe clean the slate of our past and return to the tabula rasa that supposedly existed before we began to leave our mark on the world.” This results in a dualism that sets humanity and nature at opposite poles. “We thereby leave ourselves little hope of discovering what an ethical, sustainable, honorable, human place in nature might actually look like,” wrote Cronon.

Still, many resist this admittedly disturbing revisionism. Tulane environmental law professor Oliver Houck demurs on the question of deconstructing nature and ecology. In a 1998 article he declared, “While ecosystems contain humans, human actions are not their measure. The best available measures of ecosystems are representative species that indicate their natural conditions.”

“This measure taken, the role of human beings is to manage ecosystems, and themselves, toward that goal,” maintains Houck.

The environmental historian Donald Worster worries about a new “era of agnosticism” in which the very idea of the ecosystem or nature is nothing more than fiction. Is the idea of “some comprehensive order in organic nature now totally suspect?

The famous Jesuit palaeontologist Teilhard de Chardin wrote in The Phenomenon of Man (1952) that, “The order and the design do not appear except in the whole. The mesh of the universe is the universe itself.” One must recognize great variability and discontinuities in the here and now, in the realm of contingency so to speak, with chance and randomness playing their part within a broader context of probabilities and logic. Botkin pulls back from describing this dynamism in nature as chaotic. Chance and randomness, yes. But not chaos. Is this new, dynamic view of nature really disorder or just a more sophisticated, non-static version of order?

Nevertheless, there is a bit of irony in the image of the moon in the nautilus shell in a book on discontinuities and disequilibrium in nature. Just how random is the interaction of life, tides, lunar orbits and continents rising from the sea? Neither Botkin nor Marris engage in a discussion of final causes at least in these books. But the philosopher or theologian might, understandably, be drawn into such a stimulating and important discussion of questions which science can only inform but not answer.


G. Tracy Mehan, III, served at the U.S. E.P.A. in the administrations of both Presidents Bush. He is consultant in Arlington, Virginia, and an adjunct professor at George Mason University School of Law. Parts of this article were previously published in The Environmental Forum (Environmental Law Institute www.eli.org) and The American Spectator (www.spectator.org).

No comments: