Great Extinctions and Evolution

Great extinctions are times when the number of species that cease to exist per century gets a lot higher than the average. There are always extinctions going on, and the vast majority of species that ever existed are already extinct. It seems to be a common destiny of a species to begin, to flourish, to plateau, to diminish and then to become extinct. Lots of things make species go extinct, such as the food supply being cut off, some environmental change or catastrophe such as their only habitat being flooded, long-term or short-term. New predators can evolve. More efficient species can out-compete them for food supplies or nesting spaces. And so on.

Species counts are done by checking fossil records. It seems from fossils that there were multiple times when a large fraction of the existing land and/or sea animal species ceased to appear in later fossils, meaning they became extinct. These extinctions typically happen over a geologically short time, and geology being what it is, there is a minimum time that can be determined by fossil research, so no understanding of exactly how long the extinction lasted can be obtained, if it was shorter than the minimum measurable geological interval. Nonetheless, there are multiple periods in Earth’s history when a large number of animals became extinct, up to 96% as reckoned by fossil counts on the worst of these great extinctions.

The causes of such extinctions are obviously of great interest to geologists and many other scientific specialties. The earliest one is sometimes attributed to the oxygenation of the atmosphere, meaning that all sea creatures which could not tolerate the oxygenation of the atmosphere, and correspondingly, the seas, died off. No other atmospheric change seems to have caused other extinctions, but climate change has been called on as one possibility for some of them, although not the largest ones, unless you call a temporary clouding and the subsequent cooling of the Earth a climate change. Instead, some of these largest ones are attributed to either a large asteroid strike or a basalt flooding. A controversy arose over the last one, the End-Cretaceous extinction. Someone came up with a measurement that 76% of animal species became extinct during this one.

One of the earliest theories as to the cause of this extinction was the Decca Basalt Flooding, which was chronologically pinpointed to occur at the time of the extinction. A basalt flooding, when thousands of square kilometers become like a volcano, with exposed mantle material, produces such massive amounts of dust in the atmosphere that sunlight is blocked and photosynthesis stopped. The flooding lasts for many millennia, unlike a volcano whose principal eruption lasts only a matter of days or weeks. It certainly is reasonable that this could cause mass extinction.

Later, a large crater was discovered on the coast of the Yucatán peninsula, and it was timed to also be at the time of the End-Cretaceous extinction. The crater was named Chicxulub. Asteroidal material, specifically a higher than normal concentration of iridium, was discovered all over the world and dated in sediments to have been deposited by the Yucatán asteroid. The impact would have filled the atmosphere with dust as well, although for a much shorter period. If the End-Cretaceous extinction happened within a very short period, a few years which is the dust residence time from a single near-instantaneous event, this could also have been the cause of the extinction.

It is curious that the Deccan Traps, the current geological formation from the basalt flooding there, and the Chicxulub crater are almost on opposite sides of the planet. When a rapidly flying object hits a large obstacle, shock waves are generated which move from the impact location in the direction of the incoming object. These shock waves carry some of the momentum of the incoming object, and when they strike the opposite surface, they tend to spall off the outermost layer. Spallation of this type occurs when very fast projectiles strike armor plate, for example. On something of the size of a planet, it would mean that the crust at the arrival point of the center of the shock wave would heave upward, rupturing it and leaving it no longer intact. The Deccan volcanic activity may have been going on before the impact, but the shock wave may have been the cause of the large size and huge amount of atmospheric debris that was deposited.

The crater and the traps are not on exactly the opposite sides of the planet, now, but tectonic plate motions are of the right magnitude to make it more so 60 million years ago. Both India and South America have been moving north. Furthermore, if the impact was not perpendicular, there would have been some deviance of the shock wave direction from directly through the center of the planet so it did not go from a point on one side to the exact opposite.

The crater and the traps can be used to backwards track the asteroid, and doing this shows that if the impact was in the spring or fall, the asteroid would have been traveling in the sidereal plane, where all planets and almost all asteroids reside. Thus, the two events, asteroid impact and basalt flooding, may have been closely connected.

What is considered the most serious great extinction, the End-Permian one about 250 million years ago, is often attributed either to the Siberian basalt flooding, near the north pole, or to the Wilkes Land crater, in Antarctica near the south pole. The details of these two events are much, much less certain than those related to the End-Cretaceous one, but the possibility of a basalt flooding event triggered by an asteroid impact on the opposite side of the globe exists. For some other great extinctions, there are even less certain connections to basalt flooding and asteroid impact.

What happens after an extinction? When the atmosphere returns to transparency, there is much less life around. Most of the species have gone entirely extinct, and the remaining ones were greatly reduced in numbers. It has become a field day for evolution, because the constraints on new life are largely removed. Resources are available in abundance, and competition is less. Predation is almost absent. Thus, evolution goes much faster in creating new species that it could in a crowded environment where all ecological niches were already filled. Within some tens of millions of years, hordes of new species exist everywhere.

We humans arose from the chaos of new life that occurred after the End-Cretaceous extinction. Life was not extinct, and what life existed still kept many of the genetic tricks that had evolved up to that point. Thus, evolution took off again, but from a much higher starting point genetically. This is not to say that life could not have evolved intelligence without the extinctions, but it would have taken much longer. Maybe a factor of ten in speedup happened.

What exactly does that mean for a planet somewhere in the galaxy with eukaryotic, multicellular life already started. To get to this point might have taken 3 billion years of evolution. It will take another billion years of evolution, if the rate of evolution is the same as Earth’s, to get to intelligent life. However, Earth’s evolution rate was governed and greatly accelerated by all the mass extinctions our planet has known. If there were no extinctions, or only very few, it might take ten times longer to get to that point, or ten billion years. Almost no planets are that old.

So, one interesting thing to ponder is: Can an intelligent alien civilization come into extinction in a solar system where there are no or very little asteroid impact? Is the answer: Yes, but only billions of years from now. Thus we might have another peculiarity of our solar system which might be essential to the eventual capability for contemporaneous space travel: huge numbers of large asteroids.

Overcoming the Pernicious Effects of Affluence

Affluence allows all kinds of good effects. It means that there will be an excess of benefits for an alien civilization because of productivity increases, which is almost the definition of affluence. But this excess of benefits means, if there are alien individuals who are motivated to work, that there will be spare time so that more work can be done in the development of further technology. Thus, affluence implies at least an initial increase in the rate at which technology advances. This provides feedback to the effects of improving productivity, so productivity increases even more, meaning even more time can be devoted to technology advances, and so on. A venerable positive feedback loop.

As noted in a previous post, affluence has malign influences which can outweigh the benign ones, and cause the inverse of evolution, as measured by the counts of the most successful genes in the alien gene pool, or rather the genes which make alien individuals most successful in their reproductive success. Here it is useful to recall the difference between long-term goals and short-term goals, and how alien civilizations evolve into their early industrial stages without much consideration or awareness of long-term goals for their civilization. Short-term goals propel them into various successful avenues.

Short-term goals for an individual parent in some alien civilization relative to offspring and successive generations might include both support, meaning nutrition, protection, shelter, and other physical aspects of the life of youngsters, and tutelage, meaning teaching by example or by instruction. When the technology and affluence feedback loop gets going in an alien civilization, the tutelage part runs into the problem of the change in teaching needed for a generation where technology is changing. Tutelage by parents becomes inadequate, and needs to be done in another way, and is likely to be outsourced. But tutelage has many components, and only certain components are affected by the change in technology that occurs rapidly. However, it might be that tutelage in general gets outsourced, without the breakout of components. Thus, those components which relate to motivation to work, being goal-oriented, character aspects such as diligence, persistence, honesty, open-mindedness and educability, skepticism, and much more, as well as interpersonal relationship traits, all might be turned over to someone outside the parents or grandparents or other close relations to others who might be labor-specialized to tutelage. Here can be the fundamentals for a catastrophe, if technology for training has not progressed far enough to provide good, thorough procedures for training in the latter traits. Thus the question arises, in an alien civilization, will the material and industrial aspects of technology develop faster than the training and education aspects? They will both eventually succumb to the progress of technology, but there may be a gap between them, or in more graphic terms, a chasm. Will alien civilizations tend to fall into this chasm?

On the other hand, the support side of parent-youngster relations becomes easier and easier. Technology makes fulfilling the physical needs of youngsters easier for parents, and so the two effects of this, first, more and more products are provided with variety and quantity now expanding, and second, less effort is required to do this support, implying to the typical alien that those mental traits which formerly were so needed for providing support to oneself and one’s offspring, were not so much needed and could be diminished in attention. In other words, youngsters were having the option of spending more time on consumption-related interests, and parents were seeing less need for production-related interests, both for themselves and for their young. This would tend to add more impetus to the lack of need for preserving the training components that were useful in earlier times, especially times when evolution was striking down those without these traits. This means, the chasm is wider and deeper than it would be without the two-sided effects creating it.

The antidote to having an alien civilization collapse into the affluence chasm is the early realization of the need for long-term thinking, both in its conception and development, but also in its use in guiding some of the decisions of the civilization. Very specifically, long-term thinking is needed for the civilization to recognize what the consequences of affluence might be, and how it affects the alien society. Instead of continuing the drive to develop technology to provide more and more support goods, there would have to be a parallel drive to develop technology in training, in more detail, neurology, but also in sociology, meaning how society needs to organize itself and what individuals would need to be trained in so that they could act to preserve the civilization.

Long-term thinking is needed to appreciate that the civilization has value, in and of itself, and preserving it over the long term, meaning over multiple generations, should take precedence over amassing more variety and quality in the consumption goods that their initial short-term thinking would lead them to support. This is not a simple declaration, where the civilization suddenly says that it will perform long-term goal setting and then do whatever is necessary to achieve them, but instead it is a dedication to that parallel branch of technology, so that it does not lag too far behind the material branch that produces the affluence.

Developing this parallel branch of technology will require a major commitment by the civilization, meaning the governance and the population together, to forgo the maximum amount of material support in favor of having more intangible support, which will help the society to navigate its way around the chasm of affluence. It could very well be that the other feedback effect that occurs in neurology, where the brain adapts to its environment, will prevent this change. This feedback effect will mean that as affluence turns producers into consumers, and young members of the society into dedicated consumers, that there will be more and more specialized thinking about consumption, and less and less about long-term aspects of society and the potential troubles that affluence can create. The competition between thinking about consumption details, which can be manifold and complex, and thinking about society in general, which is also complex and variegated, will dictate if a particular alien civilization will make it to the final stage of technology, asymptotic technology, where the potential for collapse from its own decisions and choices will be almost eliminated. Without the proper early realization of the nature and details of this problem with affluence, the civilization will not be at a high enough living standard for the long time needed to invent and develop space travel.

Is Affluence the Bane of Alien Civilization?

The word affluence is used here to represent a condition of having needs satisfied, in abundance, without the requirement for much effort. It seems, strangely in a sense, that this is the direction that evolution would direct any intelligent alien civilization. Evolution starts out by making species that are more and more efficient at living in their environment, but this transforms into a situation, after the invention of tool-using, to the production of a species which becomes more and more efficient at altering the environment to meet their needs.

Affluence provides the basic needs for some subset of individuals, the ones to whom the word is applied in a particular civilization, and then it proceeds to deal with the non-basic needs. This might mean psychological ones, or ones related to interactions with others, or ones related to amusement. There are probably others. For basic needs and secondary needs, after being initially met, the elements of quality and variety are introduced as affluence proceeds and strengthens. Quality and variety can blossom and produce a cornucopia of ways to fulfill needs. The certain subset of individuals who are in the affluent class or group or faction, which might be large or small or even uniform or minuscule, are less and less required to do anything at all in order to be the beneficiaries of their society’s benefits. So, a species consisting of producers of goods to meet basic needs, after technology and social organization become established and grow stronger in influence, turns into a species where some subset are simply consumers.

What happens to individuals when affluence expands within their lifetime? It might be possible to use alienology to predict what lifetimes might be conceivable with a species as they gain intelligence and turn into a civilization, but that can be left to another blog. When an individual becomes affluent, after having been gestated at a time or in a group that did not have much of it, they do not lose the habits that were ingrained in them. One way to say that is that they preserve the desires, which become needs under affluence, to be productive, and so they would seek to adapt within their changing society, or actively seek to modify it, so that individual production might continue. This would be visible as a migration of work types as technology eliminates certain classes of it.

Evolutionary success, which any alien civilization would have achieved, does not simply consist of having individuals with their needs being met. Evolution is really about reproduction and the production of future generations. That is the measure of fitness, not survival, but reproductive rate. It is reproductive rate which dictates which genetic mutations spread through the gene pool and which are eliminated. Survival chances do not figure into evolutionary success, except so far as they improve the total reproductive rate of a gene carrier through its lifetime. Among plants on Earth, there are many annuals which have had great evolutionary success, despite a fixed and short lifetime. Other examples exist among insects. Earth’s higher animals, however, are all the equivalent of perennials.

Thus the proper question to ask is what does affluence do between generations? The earlier generation, pre-affluence, learned to work to achieve sustenance, shelter from elements and perhaps lodging, and of course reproduction. The later generations learn to consume. What a generation learns is strongly affected by what the previous generation chooses to teach it, in multiple ways, such as by example and by instruction.

Each generation has a choice as to what to teach its subsequent generation, and as successive generations have less and less need for diligence and other character traits that were critical to evolutionary success, it seems very reasonable that there would be less and less concentration on those aspects of education, and more on how to consume, according to whatever fads or other social aspects dictate within the society how to establish one’s preferences among a variety of ways to consume, both to fulfill basic needs and to fulfill secondary ones. Thus it would seem that successive generations would lose the drives that evolution demands, and turn into something almost unrecognizable by evolution.

As noted just above, the only real drive that evolution cares about is reproduction rate, which must be an instinctual drive in all animals, including those aliens who achieve civilizational status. But the instincts behind reproduction can be thought of as needs, and technology can satisfy them, without requiring much effort directed toward reproduction. In other words, the affluent class can fail to reproduce sufficiently to maintain their population. Thus affluence seems to be a malign influence, which will lead to extinction for those who have it, not necessarily immediately, but after some numbers of successive generations. The subset that achieves it, and does not figure out how to overcome its influence, will die out.

Who, in an alien civilization, is most likely to achieve affluence? Clearly the subset which is most successful in meeting their own needs, under evolutionary times and just after them. This is the subset which has the genetics that allow them to be comparatively successful, perhaps dominating others, and which has mastered the use of tools, which includes the training of successive generations to use them. In other words, affluence, an inevitable result of success in the evolutionary period, both in hardware, the genes, and software, the intergenerational training, results in a potential extinction of those who achieve it, meaning that the best genes sort themselves into a group which then becomes extinct.

If evolution is continually producing these same super-successful genes and training techniques, there might be a flow of individuals out of the non-affluent gene pool into the affluent one, where they go extinct after a few generations. But evolution does not work after civilization becomes established. The qualities which are selected for under civilization are quite different from those under pre-tool conditions, initial tool use conditions, and hunter-gatherer conditions, if this particular alien species followed this path, which seems the only possible one to civilization. So, projecting the future of an alien species becomes quite murky at this point. The question to be asked is, does the most successful subset of individuals figure out the dangers of affluence, and do they any longer care about preserving the evolutionary success qualities?

If the answer is no, then the mystery of why there are no alien visitors here is unshrouded.