But how? Part five: Life!

Walkabout podcast – But how? Part 5

Having taken a break longer than I should’ve, we now return to the “But how?” series of posts that examine how things might work if we stop using religion as a default explanation. Our topic for this evening is “life.”

It is admittedly hard to believe that such a thing could come about on its own, dictated only by the simple processes of physics – until, at least, one examines it closely. In fact, even defining it is actually a tricky thing to do. Like many of our concepts that we established in the days before scientific accuracy (‘species’ is another,) life has become less obvious and more difficult to pin down as we attempt to define it unambiguously. In essence, it is a cycle of chemical and energy interactions in a collection of molecules that can replicate itself. We have to be careful, though, because we don’t want to consider ‘fire’ alive, and there still remains arguments as to whether viruses should count. Being mere strands of DNA, they do not replicate without a host cell, but given an appropriate host they both thrive and evolve.

As an exercise, let’s compare life to other properties around us, maybe something as simple and unassuming as rocks. While they don’t reproduce, they do change, quite significantly actually, and last a hell of a lot longer than any life while doing so. Able to travel down into the molten depths of the planet and back up again, simple minerals change their nature constantly, if slowly, and range from basic organic residues that we generally call ‘soil’ to gemstones and radioactive elements. The ratios of these within the crust of the planet actually allow life to exist in the first place, providing the necessary support for vegetation, a convenient and key part of the whole food chain. There’s also the interesting processes where minerals exchange places over a long period of time, producing remarkable casts of once-living creatures (in the right conditions) that we can examine as fossils, millions of years after they stopped moving about on their own.

And if you want remarkable chemical and energy interactions, it’s hard to hold a candle to the stars (sorry,) which use just four basic forces to not only concentrate energy into a form that even permits life in the first place, but creates the special elements that are ripe for energy exchange itself, through the fusion within their cores. Life just has atoms and molecules trading energy, all of which it has to get from stars; stars have atoms rearranging their structure to create entirely different elements. This process also takes a lot of time, not only to produce such elements, but to shed them when the star ends its own ‘life’ cycle and blows them away into the depths of space. Everything that we generally consider life lasts such a brief fraction of time compared to stellar processes, or even geologic ones, that it seems nothing more than a flicker.

Was there perhaps some magical moment that started it all, with the first living cell billions of years ago? And more often asked (usually without wanting to hear an answer,) is this an event that defies scientific explanation? That really depends on what is considered “defying.” At present, how this actually occurred isn’t known – yes, it has been admitted. Yet, this doesn’t mean that we have no clue, or that the process is so mysterious that it seems magical. We have evidence that amino acids, the heart of DNA, can spontaneously form in conditions similar to what early Earth must have been like, and we can see simple mechanisms to form cellular bodies; the few missing parts, such as whether proteins or DNA came first, are still being pursued experimentally. These are not considered farfetched occurrences in the slightest, but even if someone really wants to insist this is where the magic occurred, they’re parlor tricks, not exactly awe-inspiring events. We have a stack of known, or in some cases just highly plausible, chemical binding processes that explain reproductive cells, with some individual steps in the middle where our knowledge is sketchy; making some claim that ‘this little step’ is where god must’ve jumped in can only be considered grasping at straws. Bearing in mind how far in our past all of this occurred (supported by multiple lines of evidence,) it should be more amazing that we have as much information as we do.

Do we instead find animation and direction to be marvelous, the ability to function in broad ranges and exercise ‘free will’? Aside from the silliness of free will as a concept, animation isn’t something particularly unique or compelling. Plants are animated, as anyone who has battled kudzu and crabgrass can tell you, and viruses aren’t animated at all, but reproduce like crazy across entire continents by riding on coattails. Our weather systems produce motion that makes human beings look feeble, the oceans never stop moving, and as mentioned, even the planet’s crust gets around a bit. All of these come back to the simple exchanges of energy explained in the Second Law of Thermodynamics.

So, perhaps it isn’t life itself that we find so magical, but the concept usually called a soul. Though this is tricky too, since we have special rules for souls; in most cases, they have to be bestowed by a creator, and may be imbued with pre-existing qualities (like original sin.) Or they may be recycled among a populace, like in hinduism. The soul is the special part of life, motivating and distinguishing us as individuals; it can be molded, so it seems, only by our actions, yet most religions have proscriptions against taking life, even when this shouldn’t affect the key bit that merely departs the mortal vessel upon death. And of course, we have no good definition of soul in the first place, and certainly cannot show its existence. Perhaps the best support for the idea is that, while we replicate our bodies by reproducing, every person starts with a clean slate, bearing nothing that their parents learned despite how inordinately useful this might be. We’ll go into this a little further on.

The soul also seems to be regarded as the seat of emotions, as I mentioned earlier, and carries our personality out of (and sometimes into) the living shell of the physical body. Yet it also carries our memories and experiences, a curious attribute since during the period of its occupation within a body, memories and personalities can be altered or outright destroyed by mere physical damage to the brain, often by something so trivial as alcohol. This leads to the idea that the soul is controlled and beholden to the physical structure, rather than the other way around. And since virtually all emotions revolve around survival as mortals, we have little use for the soul to retain these after departing the living vessel. There are more than a few problems with the concept overall.

So not the soul, but perhaps the particular nature of human minds themselves? We actually have multiple levels of mental awareness; there’s consciousness, and sentience, and sapience, allowing us to consider bacteria as not worth very much because it has none of these, even though it does have life. And in fact, sapience is what allows us to lord it over the other animals, since we generally consider humans as the only species that has it. Except that, in terms of cognitive ability, it’s a really hard thing to pin down, and those that study animal behavior keep finding aspects of thought in other species that we used to believe only we possessed. It also bears considering that many of our older ideas were born from human conceit, especially when, not all that long ago as our species goes, we used to think the ‘savages’ from continents other than Europe failed to possess such traits.

Perspective may be important here. While we might think whales don’t possess higher cognitive abilities because they can’t use cell phones, whales may just have their own standards of intelligence, and find humans don’t count because we spend too much time killing one another, or mucking with the ecological balance. We’re pretty impressed with our own brains, but when one considers how much of our time is devoted to thinking about celebrities or getting emotional over sports, we have to face the fact that a lot of mental activity is spent trivially, and the vaunted properties of our wondrous intellect starts to unravel. The function of higher cognition certainly seems pretty useful at times, allowing us to piece out what stars are made of for instance, but much more mental effort is engaged in actually dodging such activities in favor of emotional supplication, making it hard for us to feel superior. Not one other species on the planet, to our knowledge, has ever tortured or killed large numbers of the same species to consolidate a power structure through fear, yet we do it all the time.

Lots of things on this planet have life, including rabbits, trees, slime molds, and bacteria, so considering it something special requires accepting that the planet is crawling with it. Yet despite the abundance, the effect can barely be seen even from a short distance into space, and at best, examining the Earth with a powerful telescope on Mars would only reveal a curious color to find (green) to give any indication of life in the first place. While the billions of us here on the planet have the ability to use vast amounts of resources important to us, such as petroleum and vegetation, the chances of this affecting the planet itself, much less any other part of the solar system (a tiny speck in comparison to the rest of the galaxy, much less universe,) is infinitesimal. What we affect is only life itself, including our own, but the processes that the planet goes through will continue long after we are gone, and will probably wipe away every trace of our lives in relatively short order. We can wonder whether we might find indications of life on Mars precisely because it’s so minor that it may only leave faint vestiges behind.

The energy exchanges among the elements within our bodies take place only in certain conditions of temperature, where water can be a liquid. While this seems very specific, in fact all elements undergo phase changes at different temperatures and pressures – more of them take place at extremely high temperatures, actually. That’s the nature of energy. Life is a curious thing to get fired up over, since it is strictly a brief affair, and once ended, almost none of the involved elements have changed in any way. Like ripples on a pond, a pattern of behavior and reaction may form briefly, but the water remains the same.

Even when recognizing all of this, there are very good reasons why we find life pretty cool, if not extremely important. We look at the behaviors that other species engage in and call them ‘survival traits,’ but this is misleading. The urge to see life as important (or to fear death if you prefer,) as well as the function to reproduce, are both very likely what we call emergent properties. Countless species in the early history of life on Earth may have had no such things; those that developed these had a specific advantage over those that did not, and it’s easy to see that both avoiding death and passing along the genes are key steps in maintaining an advantage, and would likely crowd out other life forms that lacked them. Upon reflection, the point where the ‘magic’ happened isn’t the beginning of energy exchange within a group of cells, but the point where such a collection of cells could replicate their properties, starting a lineage of traits. Which might have been there from the start, because of the incorporation of DNA into the cellular structure.

Believe it or not, the trend of seeing life as amazing may simply be because, ingrained deep within our systems, cherishing life is the best way to avoid death – the stronger this urge, the faster we run from predators. If we have a hard time defining what is so special about life, and why we humans hold a unique place among all other animals, the inquisitive must consider that the properties of life itself didn’t instill such feelings. When we think about it, self-preservation is by nature conceited. Many of our other traits are exactly the same way, and duplicated to various extents in other species as well. Our social instincts, sex drive, sense of fairness, reactions to threat, attractions to certain foods, and many many more, are all subconscious and evolved functions that provided benefit and thus were favored by natural selection.

But because of the method of reproduction, what we pass on to our offspring is the instruction sheet for building a human, which remains the same throughout our lives (with perhaps some very small exceptions, as has recently been discovered.) Nothing that we do throughout our lives alters the DNA that we were born with, so our offspring benefit only insofar that we actually reproduce at all, and did not die beforehand or fail to find a mate. We do not pass on what we have learned or what happens to us, only some basic properties – the structure of the brain, but not its contents. So each individual builds their own matrix of experience, their own memories and impressions, allowing us to think that we’re unique while at the very same time recognizing the similarities fostered by those duplicated instructions. We may find one hair color more attractive than another, for instance, but have the same desire to seek physical attractiveness in a mate.

In a worldview that believed in a higher purpose, the reduction of life to traits derived from natural selection may seem depressing or pointless. Except, what was that higher purpose supposed to be? In most cases, it’s to enact a plan that we’re not privy to, and thus we’re relegated to following simple instructions anyway, such as the ten commandments or some such. Or one may consider getting into heaven to be the goal, where we experience a life devoid of conflict and pain – somehow, this is not supposed to be boring or pointless itself, perhaps because too few people actually think about what life is like in the first place. To get to this paradise, we are required to be good to one another, which amazingly enough works just dandy in the evolved life form as well. I’ll leave pondering the “chicken or egg” argument as an exercise…

But can we live a fulfilled life without the grander purpose in the universe, motivated only by the good feelings we get when we provoke the proper stimuli? When it comes down to it, that’s all that we’ve ever done. We get good feelings from lots of simple functions, everything from helping someone else in need to solving a puzzle, from racing down a hill on a sled to eating a damn good pizza – our pleasures and fears are immediate and self-centered, not transcendent. Yet we still want an overriding goal, which is fine, really, but we already have one ready-built into the living system: to help the species survive and thrive. Is this really such a bad purpose?

As far as I’m concerned, it’s a much better one than any religion offers, since it doesn’t involve drawing the lines between groups of people, such as ‘sinners’ and ‘saved,’ that turn life into a competition within our own species. It reduces the conflicts by taking away arbitrary distinctions. It changes our focus from selfishness to community. And it makes us abundantly aware that life is fragile and brief, and should not be spent in pursuit of what comes after, but what we have now. It even emphasizes our position within the ecosystem of the planet, and helps us realize that, in order to achieve our goal, we have to have much greater foresight than our own individual deaths.

The answer to the question, “To what end?” then becomes very simple: “To no end!”