August 18th, 2022
I was recently re-reading some of the essays of Stephen Jay Gould, a magnificent writer and eminent scientist. He was expounding on one of his favorite themes: the directionlessness of evolution. This is his answer to the common question “Where will evolution take humanity in the future?” This is a stupid question that assumes that evolution has some sort of directionality to it, that evolution steadily pushes each species towards perfection. It’s a stupid idea betraying a gross misunderstanding of the fundamental nature of evolution. Evolution is not some deity that seeks to improve the breed. It is nothing more than the response of species to changes in their environment. Once a species is fully adapted to its environment, it stops evolving because there is no need for further change. If the environment changes, then the species begins adapting to the new environment through evolutionary processes. This is the basis of the evolutionary theory of punctuated equilibrium. The only “direction” of evolution is toward better adaptation.
But there is an important factor that Mr. Gould does not seem to have noticed. Species can only evolve by making small changes to their existing technological foundation, i.e., the DNA stored in their genes. After all, we couldn’t build personal computers until we got integrated circuits, which we couldn’t build until we had a deeper understanding of solid state physics, which we couldn’t acquire until we had developed better understanding of quantum mechanics, which…. All of our progress is based on past progress; so too is it with biological systems.
I suggest at this point that you consult some of my previous essays on the role of negentropy in biological systems. Here’s one on the prospects for life on Mars. Here’s another entitled “Life in the Sun”. A third proved to be incorrect. This fourth one, entitled “A New Physics”, presents some basic considerations. Here’s a book review with further explications of negentropy.
I come even closer to the topic of this essay in my essay “The Benefits of Catastrophes”.
Having read through all of these preliminary pieces, I am now ready to spring the new idea upon you. It is anticipated in some of the earlier essays, especially “The Benefits of Catastrophes”. It is simply stated: the biosphere has been accumulating negentropy from the sun in its collective DNA. Let’s imagine that we had a way of measuring the total amount of unique information in all the DNA of all the living creatures on the earth. Identical copies don’t count; only unique information is included in this measure. Note that this information has unquestionably been increasing over the millions of years. Before the Cambrian explosion, there was no DNA for building eyes. Before about 300 million years ago, there was no DNA for living on land. There was no DNA for managing multiple gaits until mammals began developing that capability. There was no DNA for speaking languages or designing videogames until recently.
Thus, the total information content of all the DNA on the planet has been increasing with time. The biosphere is learning! It is accumulating negentropy (information) that the sun has been showering it with all these millions of years.
Much of this learning has been triggered by internal systemic adaptations. For examples, eucalyptus trees developed a new chemical (eucalytol) that is toxic to any herbivore. This kept bugs, cows, giraffes, and other herbivores away, permitting eucalyptus trees to take over Australia (and they’ve done very well elsewhere, too). But then koala bears evolved their own modified metabolic system that permitted them to tolerate eucalyptol and live on the leaves of the eucalypus. That required completely new DNA structures to manufacture eucalyptol, and new DNA structures to tolerate it.
The biosphere just keeps getting more and more complicated. It is learning, expanding its DNA repertoire and its ability to cope with new challenges. So yes, there really is directionality to the evolution of the biosphere — towards a greater range of capabilities. But this does not imply any directionality in the evolution of a species.
We seem the same thing in the progress of any human enterprise. Science, for example, has certainly progressed dramatically. But individual scientists have a more checkered career path. Every scientist is wrong about some things. Individual scientists have their ups and downs, but science as a whole makes steady forward progress.
I hope in a future essay to apply this concept to the theory of human history.