Spiraling

One of the oft-raised technical questions concerning evolutionary processes is how they can occur within the constraints of the laws of thermodynamics when, at face value, those laws suggest that the universe should be becoming more disorderly, not more orderly. The oft-stated answer to this question is that the universe is becoming more disorderly, evolution included. Only, the universe is developing relatively small pockets of evolved, increasing orderliness at the expense of creating bigger spaces of increasing disorderliness elsewhere.

Of course, most people who ask the question aren't interested in evolutionary processes in general. They're asking about the evolution, the one that entails the origin of species. Here on earth, biologic evolution continues to play within our wonderful biosphere because out there in space, about 150 million kilometers away, a giant mass of half hydrogen, half helium plasma is running itself down, burning through its nuclear store of free-energy hydrogen much faster than we living things here on earth are using the leftover free-energy light resulting from that run-down process.

All this explains sufficiently “how” but does not answer “why” anything would evolve towards greater complexity. Couldn't the universe burn itself out as-is without resorting to having things pursue an upward spiral of complexity?

In the previous post, I explained a bit about Eric Chaisson's concept of normalized energy flows. Chaisson is defining complexity in terms of normalized energy flows. This concept doesn't directly answer the “why” question, but it does tell us that with the universe's non-uniform distribution of entropy creating regions of higher normalized energy flows, these regions are, both by definition and by common observation, more complex.

There's both top-down and bottom-up pushing going on here. A higher normalized energy flow within a system allows for greater heterogeneity of that system's parts and more diversity of interaction between those parts and therefore greater overall system complexity. On the other hand, systems possessing greater complexity are more enabled than systems possessing lesser complexity to exploit existing energy flows. This is because systems of greater complexity have, in general, greater potential for adapting to big changes than do simpler systems.

For example, this entity we call “Craig” is composed of over 200 different types of cells, all interacting in myriad ways to allow Craig to behave in such ways that cause him to consume much more energy (in the normalized-energy-flow sense) than do most other (non-living) entities in the universe. The orderliness of his body allows him to behave in a more dynamic and nuanced fashion than most other entities in the universe and to seek out and process greater (normalized) quantities of energy. This is bottom up. On the other hand, Craig's metabolic rate, which is on the order of 10⁴ erg/g/s, allows him to keep alive and flourishing over 200 different types of specialized cells, all interacting with each other in those myriad ways. This is top down.

The dualism of bottom-up and top-down pushing suggests that evolutionary processes within the universe are not merely driven by greater normalized energy flows but are driven towards greater normalized energy flows. Greater normalized energy flows allow for greater complexity; greater complexity allows for greater exploitation of existing energy flows. And so on it goes, the upward spiral of complexity, the upward spiral to complexity.

Here lies our hint of “why” evolution occurs. Evolution is the process by which the universe seeks out and exploits free energy that is otherwise “locked up” and unreachable by too-simple processes. For example, that giant mass of half-hydrogen, half-helium plasma that's running itself down happens to be emitting outwardly in all directions, as waste product, vast quantities of electromagnetic radiation. Through eons of slow and haphazard change, molecules here on earth hit upon a winning combination, in the form of a chloroplast organelle, that converts a small fraction of locally available electromagnetic radiation into more immediately useful chemical energy. There's no simple way to accomplish this feat; one microscopic chloroplast itself comprises a vast complexity of form and function. Unlocking the free energy radiating away from the sun requires complexity. Once that free energy becomes unlocked, however, even greater complexity can be built on top, using photosynthesis as a base to stair-step to ever greater complexity.

Evolutionary domains stair-steps upwards in complexity so long as there exists (1) enough immediately reachable free energy to power the evolutionary process (e.g., mating and mutation) and (2) that evolutionary process hits upon a workable manifestation of complexity to exploit free energy that was previously locked up from the simpler systems. In other words, evolution towards complexity is merely one process by which the universe maximizes entropy. In this case, it unlocks order that cannot be released by simpler systems, much like how a boulder resting atop a hill but in a small rut requires a hefty shove to release the even greater amount of potential energy in the boulder.

While I wear the push-down hat of complexity and evolution, I'll note the following example. Modern industrial civilization, with its vast consumption of fossil fuels and its order-of-magnitude greater normalized energy flow than any other form of civilization prior to it, can be roughly simplified as the natural result of the universe seeking to unlock the great quantity of stored sunlight captured within high-energy carbon bonds buried beneath the biosphere and otherwise unreachable by any other living thing on the planet. Life continued evolving different arrangements of complexity and eventually hit upon one form—us—that was able to capture fossil fuels and burn them for gain. Civilization itself stair-stepped upwards in complexity by developing ever more complex methods of extracting fossil fuels. The first oil wells, for example, were tens of feet deep. That low-hanging fruit is gone, and now we drill thousands of feet in precarious and sensitive areas. This development of ever more complex methods of extracting fossil fuels both pushes-down and pushes-up with civilization becoming more complex, and so on goes the upward spiral of complexity, the upward spiral to complexity.

However, it's important not to conflate “evolution” with “progress”. The upward spiral continues only so long as there exists ever greater quantities of free energy that are exploitable for a substantial energy profit. As the system's complexity begins to yield less energy profit than it did previously, such as by depleting the low-hanging fruit, that decreasing quantity of energy profit necessarily fails to support the existing level of complexity, and the system then enters into a downward spiral towards simplicity.

If you've made it this far through this trilogy of complexity-oriented posts, I would like for you to read (or reread) a previous post of mine, The upward spiral of complexity. In light of what and why evolution is, and taking care not to conflate “evolution” with “progress”, I think the moral question posed in that post is important for individuals to ponder.