Wednesday, September 1, 2010

Addendum to Yesterday

In my latest diatribe I wrote, again, about a fundamental law of evolution, which we might call the Law of Opportunity, and its corollaries. I neglected to emphasize what might be called the Law of Anticipation: i.e. evolution cannot anticipate future states.

I. Evolution is driven by opportunity, not necessity;
its corollaries:

1. Evolution cannot outrun ecological change
2. Evolution cannot fill an occupied eco-niche

II. Evolution cannot anticipate


Two current theories of human bipedal evolution make the logical error of evolution envisioning a future condition and hence heading that way. One is the common theory that proto-humans stood up to lessen their surface area available to the sun. The second is Daniel Lieberman’s (see the PBS show, Becoming Human) suggestion that people stood up because it was more efficient to walk that way than to walk like a chimp.

As to the common theory, aside from the problem that the sun is rarely directly overhead, if it really were the case of less solar exposure in an upright posture, the benefits of such a posture wouldn’t be realized in a chimp-like walker until many, many mutations had passed; which means that there would be no selective pressure to maintain any one of those mutations active, if each were isolated. Selective breeding only works if each mutation provides immediate benefit, not a future one.

The argument is the same for the efficiency of human walking. It’s a result of evolution, not a goal of evolution. Evolution has no goals, it simply bulges out where the walls are the weakest.

I’ll stick with habitual tool use morphing into obligate bipedalism. We know that tool use preceded the split between chimps and humans, because chimps use tools today (unless you think they might have learned from us). But chimps only use tools occasionally. I’m willing to wager that our tool habits led to the split between us and our cousins.

***

It is a reasonable question whether or not a tree falling alone in the forest has made any sound. Why, Good God, do I keep on writing this for my eyes only? So that one day in the far distant future someone will stumble upon this and say, “Good Lord, look here, this fellow had it all figured out way back when.”

It’s not rocket science, ladies and gentlemen; it’s really not. Why, oh why, am I falling here alone?

Thursday, August 26, 2010

Well, Duh

First, an apology of sorts.

For decades I thought bipedalism was connected to our aquatic addiction, although I could never quite find a convincing argument. I figured eventually someone would figure that out, too. Until it became obvious that it was tools, not water, that was crucial in getting us to stand up permanently. I was wrong about that connection and I apologize.

But it doesn’t affect the reality of us as the Aquatic Ape. It doesn’t change our demographics or our addictions. It simply brings into focus the question of when we moved to the water’s edge? It still looks like it must have happened long before we became human.

*


I am perpetually amazed at the thinking patterns of academics. Does graduate school simply drive critical thinking underground? Is lack of vision synonymous with conservatism?

The headline (Discovery News 8/12/10) : “Tool Use by Early Humans Started Much Earlier: Small-brained ancestors used stone tools to whack into large animals some 800,000 years earlier than previously thought.”

Oh yeah? Thought by whom? Those damned academics again.

So, what are they saying? They’re saying that the oldest stone tools they’ve found are 2.6 million years old and that they’ve now found cut marks dating back 3.4 million years, hence the 800,000 year difference. They’re saying “our human ancestors were using stone tools and eating meat from large animals nearly a million years earlier than previously thought.” What that is saying is that the people doing the thinking were thinking that the 2.6 mya tools they have were evidence of earliest tool use by primates. This is where I worry that they failed their logic exams. Or their statistics exams. If one finds a stone tool, knowing nothing else about it except its age, what are the odds of that stone tool being among the first of its kind ever made?Approaching zero, right? What are the odds of that tool being from the heyday of its production? Approaching 100%, eh (bell curves and all)? How long do you suspect tools of that design were in production? Hundreds of thousands of years? Millions of years? Whatever the number, you can be pretty sure that whatever tools made those marks were around for a million years or better by the time we see evidence of them.

But it’s further apparent by the quotations that academia is still confused as to why people/primates stood up in the first place. They really don’t have a clue, even though it’s another case of those confounded trees obscuring the view of the forest. It’s as if they have no idea what drives evolution.

What drives evolution? Food. And to a lesser extent sex. Basically, it’s morphology for food, ornamentation for sex. Animals will change their basic shapes in a quest for food, but they’re willing to grow stupidly long feathers to get laid. You don’t stand up because you think it’s pretty; you stand up because you can eat better.

Eat what better?

Doesn’t make any difference (although we’ll get more into that in a bit). If standing up won’t feed you better, you won’t do it. If it will, you will. Standing up to eat, of course, is fairly common. Squirrels do it, bears do it, gazelles do it, even educated fleas do it. But none of them give up the ability to get down on all fours (forget the fleas) and run like hell, should the occasion demand it. How come only primates (and we don’t know how many times) gave up speed to stand up permanently? How come we were willing to be lion fodder just so we could stand up all the time? What was so great about standing up? How could we get more to eat by being lion lunch all the time, not just when feeding?

Well, you’ve got to hand it to us. It’s the hands, silly, it’s the hands. It’s the primates’ hands that guaranteed that eventually one of them would become us. Or many of them would. Hands certainly evolved for climbing trees and manipulating food products, and they could well have forced our brains to become bigger in the process of keeping track of the minutia of separately movable digits. And once we had hands, it was probably inevitable that someone was going to start using those hands to hold tools. It’s certainly common among primates. And a tool is anything that helps you get more/better food. Chimps use tools; bonobos use tools. Neither of them is an upright, obligate walker, but they both clearly use tools, so it’s reasonable to assume that protohumans began using tools before they were upright, too.

If you look at what chimps use for tools, though, you’ll realize that none of them would survive recognizable as tools. Sticks to tease out termites would be just sticks. Stones used to break open nuts would be just stones. Teeth-sharpened spears to stab bush babies would quickly turn to dust. Chimpanzees have undoubtedly been using such tools for millions upon millions of years, yet no one has ever claimed discovery of a stash of chimp tools of any age anywhere. We wouldn’t recognize a chimp tool, if we saw it.

Nor the average early hominin tool. We wouldn’t recognize a hominin tool until we could see a manufactured edge, preferably one that has travelled.

Hands lead to tools; tools lead to upright walking. Tools say that you can be foolishly slow, slow as a sloth, provided you’ve got a good weapon at hand. And if there are a bunch of you.

When did we start throwing stones? Chimps will certainly throw things, but not, to my knowledge, as a weapon (and underhanded, if I understand correctly); not in the sense of their spears being conscious weapons. Perhaps it’s a question more of offense versus defense. We start teaching babies, as yet unable to walk, to catch a rolling ball. Do chimps ever play catch?

It’s important to realize, though, that not only wouldn’t we recognize the first tools primates used, but that the period of primitive tool use (“primitive” here meaning “unrecognizable”) must have stretched back prior to recognizable tool use by multiple millions of years, if the length of time shaped-stones stayed unchanged is any indication. Indeed, logic says its stretches back as far as the first upright hominin. (And there’s always the question of how long the transition takes/took from scrambling to genuine, obligate bipedalism.)

One thing is certainly true: brains didn’t become big in anticipation; they could only have grown as an adaptation to circumstantial pressures and possibilities. Something had to be directly driving the creation of a bigger brain; it couldn’t have happened simply because it was fun. A brain doesn’t grown to meet anticipated demands, but rather in response to immediate opportunities. There is no chicken/egg debate over which came first, big brains or tools: tools, hands down (pun intended). Nor is there any debate over which came first, tools or bipedalism: tools, no choice. There is absolutely no reason slow, weak, toothless (as in big, ripping teeth), clawless, flightless apes such ourselves would give up the only defense we had—climbing trees—unless we had an equalizer. We had an equalizer. Forget carrying food for your family, forget seeing above the grasses, forget sweating theories and standing up naked with a patch on our heads. But that spear and that rock? Don’t leave home without them.

Or your friends. Ever wonder why dogs are so smart? Maybe it’s because they hunt in packs with their friends/family. Those animals which have better communication undoubtedly eat better. And tell me, which pack hunting animals are dumb? Orcas? Don’t think so. Jackals? Huh-uh. Lions? Doubt it.

Understanding how tool use led to bipedalism and big brains doesn’t explain the human addiction to water and our choice of proximity to water for nesting grounds. We undoubtedly left Africa some 100,000 ya savvy with water. We already knew how to sail and how to fish by that time. We had added aquatic food to our diet by then. (The Flores Hobbits may have taken to sailing much earlier than us.) In any case, you can be sure that the humans who spread out from Africa 100 millennia ago were already hairless, sweaty folk who drank a lot. I wouldn’t be surprised if one day we find the gene(s) responsible for our liquid addiction, and I wouldn’t be surprised if we find out when that addiction began, as well.

And it wouldn’t be surprising to find out that the addiction is what separates us from the other hominins. (Already I worry that somewhere in the depths of the jungle a group of chimps has taken up fishing.)

*********


While we’re on the topic of surprising news about the obvious, let me comment on a report from the BBC website on August 24, 2010: “Space is the final frontier for evolution, study claim”

No, not outer space, elbow room. The report contends that “new research identifies the availability of ‘living space’, rather than competition, as being of key importance for evolution.”

Okay, I accept the reason I’ll never be taken seriously is that you can never say, “Well, duh!” in an academic journal. For years I’ve been stressing the maxim that evolution is guided by opportunity, not necessity. Admittedly, I did no research, as these people did, to prove my point. I used the old-fashioned approach: I thought about it. I’m not even going to say I did well in my logic class at the U, because I didn’t. The logic I used was pretty elementary. First I looked at the current situation of climate change and species die-off. Nobody, it seems, is saying, not to worry about the polar bears, they’ll just evolve, like our ancestors did when the forests disappeared and they were forced to walk upright. Once I’d made that connection, it was easy to see that A) animals don’t evolve quickly enough to accommodate a quickly evolving climate; and B) thinning forests could not have been the impetus for our ancestors to take to the ground. Impossible. No way. Couldn’t happen.

One of the primary problems with the standard model is the “lion lunch conundrum.” (Or “eagle lunch conundrum,” or…) How did we avoid being lunch for a predator in the interval between standing on our own two feet and acquiring tools/weapons? One solution is to not have the interval. If one assumes that acquiring weapons opened up new opportunities that led to bipedalism, the gap then becomes the reverse: between acquiring tools and standing on our feet. You can be assured we still did get picked off, but weapons leveled the playing field: we could pick them off, too.

What concerns me is the quote from the opposition, as it were. As the BBC reports it, “Professor Stephen Stearns, an evolutionary biologist at Yale University, US, told BBC News he ‘found the patterns interesting, but the interpretation problematic’.

“He explained: ‘To give one example, if the reptiles had not been competitively superior to the mammals during the Mesozoic (era), then why did the mammals only expand after the large reptiles went extinct at the end of the Mesozoic?
“‘And in general, what is the impetus to occupy new portions of ecological space if not to avoid competition with the species in the space already occupied?’”

Mt. Stearns has a decidedly curious interpretation of the facts. He makes it seem like there was a battle between reptiles and mammals, as if Godzilla and King Kong were going at it in the first rumble in the jungle. How many times, offhand, have you seen inter-species combat which was territorial in nature rather than one side looking at the other as lunch? When has anyone caught on film the fierce war waged between bears and blue jays for control of the huckleberry fields? I have a feeling something was awry in my childhood education, as I seem to have missed those documentaries. Has Mr. Stearns forgotten the fact that reptiles appeared on earth a hundred million years prior to the first mammal? A hundred million years is a long time to fill up all available eco-niches. What’s amazing is that mammals appeared at all given the reptiles’ dominion.

Mr. Stearns is apparently unaware of or has forgotten (which is troubling, considering his profession) that basic evolutionary axiom: that a species cannot evolve into occupied space. It’s a corollary of the rule that evolution is driven by opportunity, not necessity. This is the sort of stuff that should be taught day-one in evolutionary science, so it’s disturbing that a practitioner in the field should not be aware of it. What sort of fight is he envisioning? If not hand-to-hand (paw-to-paw, paw-to-hoof) combat, then fighting for resource dominance? We’re back to the bears and the blue jays.
There are no “necessities” in the living world. There is no necessity for life on this planet. Most planets in our experience have no life on them; it’s obviously not a necessity for any given celestial object. It only arises where it can, not where it has to, and that distinction maintains itself forever. You do what you can, not what you have to to survive. If there’s a gap between need and ability, you die.

The second portion of Stearns’ argument, “what is the impetus to occupy new portions of ecological space if not to avoid competition with the species in the space already occupied?” makes it sound like one evolves to avoid danger, which is impossible. It again implies direct inter-species competition, which is not seen in nature. The lion and the vulture do not fight with each other over the spoils of a kill, they fight among themselves. The vulture doesn’t evolve with the hopes of knocking off the lion as king of the kill. It doesn’t even evolve to outpace the jackals. It evolves to be a better vulture than its neighbor.

And we didn’t evolve a bipedal life because chimpanzees were taking over the forests. Instead, becoming bipedal opened up previously nonexistent eco-niches: that of armed primates.

One wonders what sort of competition Mr. Stearns envisioned took place between the reptiles and the mammals after the die-off of the dinosaurs? Reptiles didn’t disappear during the Great Extinction, even in Connecticut there are lizards to this day. In Mr. Stearns’ view, it would seem, that the reptiles suddenly lost their competitive punch, or how else to explain that they couldn’t simply outmaneuver the mammals again, if that’s what they did they first time? Why did they loose their “competitive superiority,” as he put it? Unless, of course, they never had competitive superiority to begin with. Unless it was a case of first come, first serve, which is appears to have been.

To reiterate, the Basic Rule and its corollaries are:

Evolution is driven by opportunity, not necessity.
1. Evolution can not outrun ecological change
2. Evolution can not fill an occupied eco-niche


Accept neither wooden nickels nor excuses.

Saturday, July 24, 2010

Play Ball

Do chimps ever play ball? Do little chimps ever play catch? How about bonobos? Orangoutangs?

We start to play ball with babies as soon as they can sit up. We don’t wait until they can crawl; we start right off rolling the ball to them, and pretty quickly they try rolling it back. Sure, there’s a lot of social interacting going on, but at the same time they’re learning the most important motor skill that separates us from the other apes: how to hit something with a rock. (Why is it important for the quarterback to be able to hit the running receiver? Because the gazelle won’t stand still.)

Chimps, of course, certainly do throw things, and some, I imagine, get fairly good at it; but nobody’s worried over at MLB or the Dominican Republic that apes are going to take over the pitcher’s mound. Hang in there, Johan Santana, your job is safe.

But when chimps load up for a war party, they don’t load up with anything. They don’t carry along a cache of rocks, and they don’t fashion any spears, as they do when they’re singly hunting bush babies. And anyway, they never throw their spears, they only poke things with them. When a troop of chimpanzees sets off to invade a neighboring territory, they do it bare-handed; portable weapons are not part of their mind set. Needless-to-say, they don’t go marching off standing up; no need.

But us slow pokes. We were willing to forgo speed, just to stand up. We were willing to abandon our ability to scamper like hell, up trees, if necessary, just to stand up. Had to be something pretty important. Had to be something that was a constant, not just an occasional pressure. See over the tall grass? Oh, come on, 24-7? Cart food to the old lady? How come she learned to stand up too? Other animals seem able to cart food to families without growing hands.

But once an ape caught on to the idea that, if you were always armed with a spear and a few rocks, a bunch of you could go almost anywhere and have a lot less fear of being eaten on the way (providing, of course, you had sufficient water, if you were human-to-be). If you were always armed and always on the ready, you’d probably eat a lot better and so would your kids. Of which you’d have more with a higher survival rate, etc. Standing up to thrust a spear doesn’t require a large advance in skills for any ape, but accurately throwing rocks required mastering a set of skills heretofore little used in any of the animal kingdom. There just aren’t a lot of stone or nut tossing carnivores out there. No one has to worry that they will be attacked by boulder-wielding gorillas. Learning that skill put us in a class by ourselves. But if you’re going to be successful, you’re going to have to cart those weapons around the whole day and be at the ready.

But it worked and consequently we were suddenly dining a whole lot better than our weaponless cousins. We began to separate ourselves from the other apes by eating larger and larger quantities of meat. Standing up to hunt made all the difference (thank God we didn’t have vegetarians back then, the debate would have snuffed us out).

Coda:

Let it be noted that randomly selected, unaltered throwing stones would have been employed by apes for millions of years before anyone hit upon shaping the stones and putting on a cutting edge; and that sharpened wooden spears would never have survived the eons between then and now. In other words, when we first see stone cutting tools, we are well into the middle of weapon/tool technology, not at the beginning.