Bio-Advance

The subsequent two factors in the Drake Equation, f_i and f_c, which concern themselves with the advance of life in complexity until it achieves intelligence and tool-using civilization, are usually considered together, and often an arbitrary benchmarks on an inevitable progression of bio-abilities. Some years ago opinions concerning biological advance would have been largely intuitive. Now the answer is essentially certain. Life inevitably advances in complexity. This insight is the gift of one of the twentieth century's great discoverers, Ilya Prigogine s1Prigogine 1980 s2Nicolis & Prigongine 1977.

Prigogine solved the paradox of an evolving life-force in a thermodynamically dissipating universe by demonstrating the following:

If an entity is both unstable (i.e., malleable, alterable, flexible, changeable) and self-organizing (i.e. capable of structuring and maintaining itself),
and such an entity is "perturbed" (i.e. challenged, altered, stressed, damaged) by some force,
then that entity will re-organize itself taking the perturbing force into account. It will tend to maintain its previous talents, while adding to them something which contends with the offending perturbation. It will become "more clever" in existing.

Such great insights always have the characteristic of being "obvious," once someone finally sees them.

Life forms are quintessential "unstable, self-organizing systems." Unless the perturbations they face are so disruptive as to kill, they will advance, they will evolve. Although this "advance," through extinctions and difficult times, is not uniform, the arrow of time and the arrow of bioevolution generally are in step.

All accross Earth's surface and Earth's time, perturbations and restructurings have been taking place. Uncounted numbers of biological trials and errors have offered themselves up for testing by the physical and living environment. The winners have survived. Some writers have suggested that we make very risky judgments about advanced life in the galaxy when we base our thoughts on the "single case" of life on Earth. "Planetary chauvinism," Carl Sagan and others call it. Surely life fills the galaxy in unthought variations. Perhaps. But, whereas we are probably at great risk to apply specific macroscopic appearances from Earth forms to other galactic life, concerning the fundamental patterns of life there may be little or no risk at all. The patterns of design and basic structures of our life forms are neither random nor inflexibly linked to some peculiar or singular set of conditions on this planet. Our life forms do not represent "one case." They are the consummation of the experiments of billions of years to find the tools of survival, the structures and behaviors that work. And we have already seen how much alike the earthlike physical environments throughout the galaxy should be.

Support for the idea of common patterns of advanced life comes from more than intuition. Concrete evidence lies all about us. It is called convergent evolution. In isolated ecologies we see life forms which not only occupy similar niches but have also developed similar sizes, shapes, functional structures, and even behaviors. Life, through all the experiments-to-exist, finds and refinds the paths to success. Convergence of form and behavior implies that "getting it right" involves a limited number of structures and abilities for each task. Our world separately evolved two kinds of bats, animals so alike that we didn't recognize their evolutionary separateness until very recently s3Pettigrew 1986. We have marsupials almost indistinguisable from placentals. We have mammals (dolphins) looking like fish (sharks) looking like reptils (mosasaurs). We have two dozen independently developed kinds of eyes. Some things obviously work and some don't. Some are so valuable that they are bound to arise many times. As biologists begin to take more and more physics into account in their discipline, it will be seen that the forms and abilities of organisms can not be infinitely variable in their basic patterns. And the same physics will operate throughout the galaxy s4Reif and Thomas 1986.

Parallel or convergent evolution is a common phenomenon. Hence we see on Earth repeated, but separate, appearance of advantageous characteristics such as multicellular organisms, eyes, or wings. Such evolutionary developments are therefore not unlikely in living systems elsewhere in space s5John Billingham, NASA Ames Research Center, 1986.

Intelligence, or encephalization, has been shown to be part of the strong trend of complication in bio-development as well s6Russel 1981, and our own advanced intelligence is viewed as the product of a sequence of events which could as well operate on other life forms of our world should have failed.

The view that mankind's development was a lucky chance, and the only one, may perhaps be not quite right. It may well be that nature was making a number of experiments in homonization... It's quite conceivable that, given the same starting conditions, and given enough time and evolutionary opportunity, it could happen more than one s7Philip Tobias, University of Witwatersrand < Ridpath 1975.

Reflecting on these matters, David Attenborough argued that, if man became extinct and vacated the top of the intelligence niche in Earth's ecologies, there exists a modest unobstrusive creature somewhere that would develop into a new form and take our place s8Attenborough, D.: Life on Earth, London: Collins.

Without quibbling about the exact details of similarity between ours and other planets' life forms, the consensus of the litterature upon the Drake Equation factors f_i et f_c is: once life begins on a long-existing earthlike planet, the advance to intelligence and tool-using civilization is inevitable. f_i and f_c are "1."

Something like the processes that on Earth led to man must have happened billions of other times in the history of the galaxy. There must be other starfolk... these non-human creatures of great learning have doubtlessly been sending explorative expeditions through interstellar space for countless millenniums s9Carl Sagan, Cornell University.