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A recent discussion about young Earth creationism has got me thinking about my view of the world.

Young Earth creationism (YEC) is such an easy target that is is tempting to be misled, and I realize that I have often fallen into the trap I’ll shortly describe.

YEC proponents claim that the Earth and in fact all the universe is something like six to ten thousand years old, that humans and animals appeared in pretty much their modern form at the beginning of time, that most extinctions occurred and geological formations like the Grand Canyon appeared due to a single worldwide flood, and so on, and that God was responsible for it all. The first part of this argument is so bad that it’s easy to get stuck there, and never get to the second part of the argument, which is in fact infinitely worse. This is the trap.

We can demonstrate that the universe is much older than a few thousand years. We can show that humans and animals have evolved. We can present evidence for the slow formation of landforms. But these demonstrations have no effect on YECs. Why? Because that’s not what YEC is truly all about. Instead, and this is the key point we miss, YEC is actually all about the second statement “God did it.” That’s a statement we can’t refute – which ironically is precisely what makes it such a spectacularly bad explanation.

Old-Earth creationists, intelligent designers, and so on, are far more clever than YECs, and we can see in their arguments the crux (no pun intended) of the issue. They might say, “Fine, we accept all that science and history and geography demonstrate. The universe is 13 some billion years old and began with a Big Bang. But God still did it.” Even though this argument matches (by definition) all the findings of science, it is still a bad explanation.

Let’s set up an imaginary scenario in which YEC or some other similar claim is not such fish-in-a-barrel easy pickings in order to explore why. Suppose an upcoming mission to the Moon discovers, inscribed in the original Hebrew, a replica of the Ten Commandments.

ten-commandments-400

You can imagine the mixture of celebration, consternation, “I-told-you-so” finger wagging, and so on that would ensue. Would this discovery prove the existence of the supernatural entity called God?

Many would be convinced. If I’m honest to my convictions, I have to say that such a discovery would not, in fact could not, convince me. For even with evidence like this, the idea that “God did it” is still a spectacularly bad explanation. If I accept the idea that life (not just science) is all about finding good explanations, then even with the inscribed tablets from the Moon I would have to reject the “God did it” argument as a bad explanation.

What would I say instead? First eliminate the obvious. Is it a hoax? Is this a modern Shroud of Turin, created by Earthlings with an agenda? If we can eliminate that by, perhaps, obtaining an accurate date, demonstrating that this material originated on the Moon itself, showing that the letters were carved in a way inconsistent with a hoax, and so on, then we move on.

Could it be that the tablets arose via natural processes? This is an exceedingly bad explanation. However, it is still better than the idea that a supernatural entity acted in our universe, for the simple reason that the tablets themselves must contain far less unexplained order than the entity that supposedly carved them. Even so, I’d be quite unsatisfied with such an explanation.

No, my conclusion, I believe, would be something like this: the stories of the Old Testament have more truth than I’d supposed. Perhaps there were original tablets, maybe even a person named Moses who received them, and perhaps he even thought he’d received them from God. But such a God, acting in our universe, must be part of our universe, must be, perhaps, a creature like the “Q” of Star Trek, an immensely powerful, knowledgeable, yet still evolved being of our universe, a being that still obeyed and obeys the laws of physics.While we have no evidence for such a race (other than these imaginary tablets, of course), this is still a far better explanation than the supernatural notion that “God did it.” Faced with magic, we must try to discover how the magic works.

What was the point of this imaginary exercise? Just this: the fact that YEC is demonstrably wrong is beside the point. Even if, through some utterly unlikely chain of events, modern science were to discover that the YECs were right all along, that the Earth really is only a few thousand years old and so on, such a discovery in no way validates the much worse claim that a supernatural entity known as God is responsible for our existence. Supernatural explanations are always bad explanations. This is why “debating” YECs (or old Earth creationists, or intelligent design advocates) is pointless.

This argument might feel uncomfortable. It seems like dogma, this out-of-hand denial of the supernatural. Isn’t this the equivalent of a religious claim, an unproved (and unprovable) belief that the universe makes sense? Consider the alternative (which is very much the “world” we live in, and by world I mean society). She claims “God did it”. He claims “The Flying Spaghetti Monster did it”. Another claims Allah, Vishnu, the Raven, the Great Turtle, and so on. Supernatural claims are infinitely variable because they are definitionally untestable. The only path forward we’ve ever found, the only way we’ve ever made any progress, is by assuming that the world makes sense.

Arthur Clarke famously said “Any sufficiently advanced technology is indistinguishable from magic.” Bull, I say! If you believe in reason, you will analyze the “magic”, find out how it works, and change your view of the world to accommodate the new information. But you won’t give up on reason. If we decide that “magic” is both real and unexplainable, we’ve lost.

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Some work I’ve been doing recently plus an exciting report from the Kepler mission has got me thinking about the Drake equation and extraterrestrial civilizations.

I haven’t found a great Drake equation online, but here’s one that’s ok, and will serve my purposes. Go ahead and try it, then come back and we’ll compare numbers:

http://easycalculation.com/other/science/Drake-equation.php

So what did you get? Are you optimistic about the number of civilizations in our galaxy?

As I think about the question, “Do you believe in extraterrestrial civilizations?” it occurs to me that there are in fact three possible responses. The first is no. The second is yes. The third is, “what a ridiculous question.” Let me explain.

Change the question to, “Do you believe in China?” At one point in Western history, such a question might have logically received a yes or no answer. Eventually, though, the existence of China became obvious. Today, no rational person could deny the existence of China. The proper answer is, “what a ridiculous question.”

We can easily imagine living in a world where the question, “Do you believe in extraterrestrial civilizations?” would equally be silly. If extraterrestrials had obviously altered their environment, if they were visiting our planet regularly, or if, in fact, we had been colonized by these beings, there would be no denying the existence of intelligence other than us.

We don’t live in such a world. That’s a data point. And that data point informs my thoughts about the Drake equation. If you believe (as I do) that a civilization can span an entire galaxy, you have to ask, “Where are they?”

Here are my numbers; let me know where we differ and why.

R (in this version of the Drake equation it’s the number of Sunlike stars in the galaxy – in others it’s a rate of star formation)

This should be the most certain number in the entire equation, but it turns out to be more difficult than you might suppose. The key is “Sunlike”. How wide or narrow a net does that cast? Could stars in double star systems still be Sunlike? What about stars that lack metals, because they didn’t form near enough to supernova remnants? What about stars too near a black hole or other radiating body? I’m going to use a number of 100 billion here, although I suspect this number may be a bit too high.

Fp and Ne (the fraction of stars with planets and the number of Earthlike planets per system)

This is where the new Kepler data comes into play. Kepler gives us a number of around 20% for Earth-sized planets in an Earthlike orbit – pretty large, considering all the ways things might go wrong in a Solar System. Here I’m assuming that to be Earthlike a planet merely has to be the right size and at the right distance. There might be all sorts of other factors I’m leaving out, like needing a big Moon and so on. But I’ll combine Fp and Ne into 20% (times 1), even though I think it might be too high.

Fl (the fraction of Earthlike worlds on which life begins)

I’d always been highly optimistic on this number, until I read an argument by Paul Davies in The Eerie Silence. My original feeling was that because life seems to have appeared on Earth as soon as it possibly could have, life’s origins must not be all that difficult, given a few million years and a planet’s-worth of the right ingredients. Davies’ argument made me question that assumption. Here it is: we’re here. It took almost 4 billion years for us to get here. At best the planet has another billion years left where our evolution would have been possible. Perhaps it is only on that (maybe small) subset of worlds where life started quickly that intelligent life had the time to develop. So of course we find ourselves on a world where life started almost right away.

Maybe. It’s an interesting argument. But if life was an incredibly lucky accident, why couldn’t complexity have happened a lot faster via its own set of lucky accidents? We’ve only just started this origin of life business, and there are already so many possible channels, it seems to me likely that life can get started quickly, and unlikely that there’s some fundamental barrier to every path.

This is one factor that could potentially get a lot more certain very soon. If we were to discover just one independent origin of life, either on Mars, in the biosphere signature of an extrasolar planet, or even here on Earth, then the likelihood of life beginning elsewhere would shoot up. I think this will happen – the stuff of life is just too common in the universe for life’s origin to be some rare one-time occurrence on this planet. I remain guardedly optimistic on the question of life and enter a figure of 90% for the number of Earth-like worlds on which at least simple life gains a toehold.

Fi (the fraction of living worlds that develop intelligence)

Now things get interesting. The same argument that makes me believe life is common also leads me to believe that complex life, animal life in particular, is perhaps exceedingly rare. The counter-arguments are that dolphins, crows, even octopuses have evolved intelligence essentially separately from humans. OK, sort of. But they’re all animals. Consider this chart:

tree of life

Once upon a time we looked at the natural world and saw just animals and plants. Animal, vegetable, mineral, remember? Then we made a concession to the oddballs and called them protists. Now we look out there and see a plethora of groups, with only a tiny few (the plants, the animals, and the fungi) showing a move toward complexity. We, it turns out, are the oddballs. And of these oddballs only animals have developed even a little intelligence. How much would change if that one, thin twig holding animals had been snipped early on? To put it another way, how much would you miss any of the other branches?

The late Lynn Marguils and her colleagues developed an alternate tree that emphasized symbiosis over branching – i.e. we’re not just animals. We’ve incorporated other beings into our ever cell. Mitochondria for animals, chloroplasts for green plants, even our own DNA-holding nuclei. All these were once free-living organisms, members of one of those other branches. That, I think, makes my point even stronger. How many events had to happen just so to make complex life even possible? What if even one had turned out differently? Complexity, history seems to be telling us, might be quite rare, and intelligence rarer still.

The calculator I’m using here only goes down to one in a million for Fi. I think that might still be too optimistic, but I’ll go with it for now.

Fc (the fraction of worlds with intelligence that develop civilization – which we’ll define as the ability to be noticed over cosmic distances, via radio or another medium)

We are so very, very new at this technology thing. There are people alive today that still remember the very first radio broadcasts. Even though we’re a young species, the amount of time we’ve had a technological civilization is a tiny fraction even of that number. It took us a long time to get here. Might we have not made it at all?

As a test case, I point to the Neanterthal. Here’s a species that arose, just as we did, from African ancestors. Neanderthals expanded into Europe and Asia, became adapted to cold weather, evolved huge brains (in many cases bigger than ours), learned to use fire, probably had spoken language, hunted the largest and most dangerous creatures in their ecosystem, and of course made and used tools. But here’s the rub. Neanderthals developed a stone tool kit and then did not change that kit for 100,000 years! It’s astounding to even think about that level of stasis. Life 200 years ago is practically unrecognizable today. Even pre-civilization, our ancestors were inventing bone fishhooks, musical instruments, art, jewelry, sewing needles, and on and on. But the Neanderthals stood stock still for a hundred thousand years.

Suppose we had never come on the scene? Could all of life’s pageant, nearly four billion years of evolution, have resulted in the Neanderthals and then have gone no further? Why not? The Neanderthals stood technologically still for 100,000 years. Would they ever have developed radio telescopes, if the world had been left to them? Why would they, when in 100,000 years they didn’t even learn how to fish?

What if, at any time before today, a giant asteroid had come our way? Not only could the Earth have not prevented an impact, but not one species on Earth would even have known it was coming, or even that such a thing might be remotely possible. No Neanderthal was ever going to deflect an asteroid.

Neanderthals are just one example of the move away from complexity. When one studies the evolutionary record, one sees again and again a move away from innovation and creativity and back toward the tried and true. Ancient apes evolved into innovative chimpanzees and of course our clever ancestors, but also into non-innovative gorillas and orangutans. Australopithecines gave rise to the first homo, but also to their own robust forms with giant jaws and sedentary lifestyles. And homo itself gave us the hobbits, H florensis, as well as the Neanderthals. An honest assessment says there are plenty of ways to not develop radio astronomy.

And then there’s the fact that even we H. sapiens could easily have never experienced the Enlightenment, could easily have disappeared without ever understanding what a star is, let alone what a radio wave is. Both pre-history and history suggest to me that arriving at one achievement (like a big brain) is absolutely no guarantee of moving up to the next one. Maybe I’m too pessimistic here, but again I’m going to pick the one in a million option.

L (the lifetime of a technological civilization)

Finally we come to the lifetime question, where hand-wringing and moralizing abound. We’re going to blow ourselves up. We’re going to create nanobots that will turn everything to grey goo. We’re going to unleash a genetically modified disease that will wipe us out. We’re going to use up all our resources and slowly choke on our own exhaust, buried in our own garbage.

Well, maybe. It’s all so moralistic. We’re too successful. We’re too powerful. Our knowledge is greater than our wisdom. Admittedly, humans are different from any species that has ever lived on this planet, so comparisons may no longer work. But keep in mind that too much of anything isn’t what brought on extinction for virtually every species that has ever evolved on this world. Rather, these species went extinct precisely because they were living within their means, and then something came along that did it better.

Similarly, human societies have not fallen due to overuse of resources. Rather, they have fallen due to lack of knowledge.

I take a different view. I learned from David Deutsch that the only infinite future is one that is unsustainable, one that depends upon the next innovation. I learned from Steven Pinker that we’re not getting worse, we’re getting better. We’re smarter, more moral, and less violent than at any time in our past. I believe this is (once an event like the Enlightenment happens) the most likely path for any intelligent species. Even if it’s not, I think we at least see how such a future is possible. And if it’s possible, then surely one (and it only takes one) civilization will make it. Not just to a long-lived civilization, but to a galaxy-transforming civilization.

Now we return to my original point. Where are they? If I’m right, if civilizations aren’t limited even by the life of their own star, why don’t we see evidence of the extraterrestrials in our neighborhood? Let’s run the numbers. I’m going to put 100% in for L, even though of course this wouldn’t apply to the home star of the civilization – since it certainly takes some time to evolve. It refers, instead, to the overall lifetime of the universe, and reaches into the tens of billions of years.

What’s my final number?

0.036

Wow. I’m saying that in this galaxy we are very likely alone. That’s why we don’t see them. They’re not there.

But wait. The universe is very large. Multiply that 0.036 by the number of suitable galaxies we can see, maybe another hundred billion. What do we get?

3 billion

My argument is that of all the galaxies we can see in the sky, roughly one out of a hundred is home to a technological civilization that is even now in the process of colonizing their galaxy. We’ll probably never talk to these beings, but we still might know they’re there. How? By their works.

If these beings are truly independent of their own star, then they must of necessity be “terraforming” their own galaxy to make it more suitable for themselves. Perhaps they’re building Dyson spheres around clusters of stars, so as to collect every bit of energy it gives out. Perhaps they are altering the rates of supernovas or gamma ray bursts, so as to protect themselves from catastrophe. Perhaps they are harnessing the power of black holes in a detectable way. Perhaps they are altering galaxies in ways we can’t even imagine.

When the signal comes, and I believe it will, it won’t come from our own galaxy. It won’t be a radio transmission welcoming us into the federation of planets. Instead, the signal will come from a galaxy far, far away, a galaxy that at first looks a little peculiar. As we examine its feeble light more closely, as we one by one eliminate natural explanations, we’ll slowly realize that something extraordinary is happening (or rather, did happen, as we’ll be looking into a long-ago past, delivered on light beams millions or even hundreds of millions of years old).

And what would such a discovery mean? Just this. Someone made it. Someone figured out how not to push the red button, how not to release the grey goo nanobots, how not to destroy what we’ve created but rather work together to make a society that might last not just a long time but forever.

We may never know much about these beings’ science, and even less about their art, their religion, their philosophy. But we will know that they found a way. And so might we.

HubbleDeepField.800px

The Hubble Deep Field, around 3000 galaxies in a tiny patch of sky. Of these, perhaps 50-100 are home to a billions-year-old civilization. Are any of these galaxies even now sending us light that will one day reveal an extraordinary truth?

As much as I thrilled to the technology Melville described in Moby-Dick, I particularly enjoyed laughing at Melville’s bad science. Some of his errors are wholly understandable; Melville lived in a pre-Darwinian world in which biology remained a great mystery. But some of his mistakes reflect what will seem a ridiculous statement, yet one I believe I can defend. Melville, I argue, lacked imagination.

Let’s begin with Darwin. Charles Darwin was born in 1809 and sailed around the world aboard the HMS Beagle between 1831 and 1836. While this voyage helped Darwin formulate his ideas on the evolution of life, these ideas didn’t solidify until the early 1840s, and were not published until 1856, five full years after the publication of Moby-Dick.

This pre- vs post-Darwin worldview is most obvious when Melville tries to classify whales in his chapter on cetology. The first mistake occurs before Melville has even begun his classification scheme. For Melville, “a whale is a spouting fish with a horizontal tail.” (p 198). He then goes on to classify whales by size as their most important and diagnostic characteristic.

Here’s the thing: in a pre-Darwinian world, there’s no particular sense in which we could say that Melville was wrong, either about whales as fish or about their familial relationships. Without Darwin’s insight of common descent, classification is nothing more than sorting. There are many, many ways to sort everyday objects – by color, by utility, by composition, and so on. Not until Darwin showed that all animals evolved from a common ancestor could there be exactly one correct way to classify them. That one way is to follow the concept of adaptive radiation. The history of life is an ever-branching tree, with each branch a species. Pre-Darwin, anyone might make an argument for or against whales as fish or as mammals. Post-Darwin, there is only one correct answer. Whales are mammals, because their ancestors were mammals.*

*Ironically, modern cladistics, which follows logically from Darwin’s insight, shows us that whales (as well as elephants, eagles, rattlesnakes, and we) actually are fish, because deep, deep in our history, we all have fish ancestors. But this is not the sense in which Melville claims whales as fish.

There’s a revealing episode later in the book in which Melville comments on the very human-like hand bones found in every whale’s fins. Melville is commenting on how strange it is that whales’ bodies so poorly match their skeletons. He says this tendency, “is also curiously displayed in the side fin, the bones of which almost exactly answer to the bones of the human hand, minus only the thumb.” (p 383) What I find curious is that it never occurred to Melville to ask why the one sort of creature in the ocean with both warm blood and lungs also happened to mimic the mammalian hand under its finny flesh.

A humpback whale skeleton – note the tiny hip bone remnant, and the finger bones embedded in the fins.

As mentioned, all this is perhaps excusable; after all, Darwin’s insight was genius. It took a Darwin to show us exactly what whales (and all other animals) were. But I think there’s a deeper issue in much of Melville’s scientific philosophy. He seems trapped in worldview from an earlier time, a time when nothing much ever changed.

For instance, when discussing cetacean art (art of whales, not art by whales!) Melville makes the following bizarre statement: “(A)ny way you look at it, you must needs conclude that the great Leviathan is that one creature in the world which must remain unpainted to the last.”(p. 383) In other words, we’ll never have a good rendering of the whale in life.

A 0.20 second Google image search makes a liar of Melville “about 565,000,000” times. Not fair, you might say. How could Melville ever have predicted the way in which image technology would explode? Yet this is exactly my point. From the moment our ancestors created painted images of the beasts they hunted upon dark and rough cave walls, people have worked to create images of their world. This desire for accurate pictures has never changed, though our technological skill has certainly increased. I take it as a failure of imagination that Melville, steeped as he was in the ingenious technology used to kill whales, could not envision that technology might someday allow us to render those same whales, not into oil, but into faithful images.

More seriously, in chapter 105, Melville asks the question, “Will He (the whale) Perish?”

(W)hether Leviathan can long endure so wide a chase, and so remorseless a havoc; whether he must not at last be exterminated from the waters, and the last whale, like the last man, smoke his last pipe, and then himself evaporate in the final puff. (p. 673)

Melville’s answer is no, we humans will never make the slightest dent in the worldwide whale population. His reasoning, once again, reveals a lack of imagination from this teller of tales. Melville argues that a single whaling ship, on a four-year cruise, is happy to kill and render perhaps forty whales. Such a small number could not possibly affect the whale’s population. He also argues that the ocean is vast, and if whales are chased away from one particular portion of the ocean, they can always relocate to another. Finally, Melville argues that as a last resort whales can always find refuge under the ice, where no human hunter can ever go.

We know, of course, that Melville’s argument fell sloppy dead on all three counts with the coming of more and better technology. Exploding harpoons, more efficient factory ships, and, of course, fossil-fuel engines that could outrun, outmaneuver, and outlast any whale anywhere in the world changed the equation dramatically.

In a related argument, Melville described the blue whale (he called it the sulphur-bottomed whale) quite briefly, merely stating that “he is never chased; he would run away with rope-walks of line.”(p 204) This to me reveals all, for when whaling began the same might have been said of the sperm whale. No one knew how to hunt it. Then people learned how. Why wouldn’t further learning, further ideas, further technology, reveal a method for hunting this largest of all creatures? Of course, that is exactly what happened, as the technology of World War II, once used to kill people, was soon after turned upon the blue whale, resulting in that magnificent animal’s near-extinction in a matter of decades.

All this makes me think of both David Deutsch’s book, in which he makes a statement so simple and yet deeply profound – we cannot know what we have not yet discovered – and Steven Pinker’s, in which he describes how people have changed over time. In particular, Pinker makes the argument that we today are better at reasoning than were people in the past. I was reminded of this forcefully when I read Melville’s argument that whales are fish. After describing the reasons forwarded by Linnaeus for putting whales into the mammalian class, Melville dismisses these arguments by submitting “all this to my friends . . . both messmates of mine in a certain voyage, and they united in the opinion that the reasons set forth were altogether insufficient. Charley (one of the narrator’s friends) profanely hinted they were humbug.” Now there’s an airtight argument for you!

This is so like Pinker’s discussion of the Flynn Effect in IQ testing, reflecting our growing ability to reason. From page 776 of that book:

Consider a typical question from the Similarities section of an IQ test: “What do dogs and rabbits have in common?” The answer, obvious to us, is that they are both mammals. But an American in 1900 would have been just as likely to say, “You use dogs to hunt rabbits.” The difference, Flynn notes, is that today we spontaneously classify the world with the categories of science, but not so long ago the “correct” answer would seem abstruse and irrelevant. “’Who cares that they are both mammals?’” Flynn imagines the test-taker asking in 1900. “That is the least important thing about them from his point of view. What is important is orientation in space and time, what things are useful, and what things are under one’s control.” (p 776)

Pinker goes on to describe how this change Flynn discovered makes a real difference in our lives:

Flynn suggests that over the course of the 20th century, scientific reasoning infiltrated from the schoolhouse and other institutions into everyday thinking. More people worked in offices and the professions, where they manipulated symbols rather than crops, animals, and machines. People had more time for leisure, and they spent it in reading, playing combinatorial games, and keeping up with the world. (p 778)

All this may seem pretty academic. Big deal that Melville got the science wrong – he was writing over 150 years ago! I think, though, that Melville’s failure is telling. Understanding the world through science, particularly since the Enlightenment, has always led to greater control and influence over that world. As we will see, for Melville such control, even such understanding, is illusory. This illusion of reason speaks to the moral struggles that form the heart of the book. It is those moral struggles to which I turn next.

There’s an interesting cover article in Scientific American this month. A researcher has found a potential human ancestor in South Africa called Australopithecus sediba. This is surprising because it seemed until now that the Australopithecus to Homo transition happened in East Africa, not South Africa. It’s always the case that researchers argue for their own find to be the keystone species in some great transition, and the argument reminds me of nothing so much as the 2000 presidential election in which supporters of Gore knew that Gore got the most votes, while supporters of Bush were just as convinced that their man had the numbers. How did either side know?

Australopithecus sediba - still a small brain

But that’s not the interesting part. The most interesting statement came early in the article by Kate Wong. Here it is:

“Conventional wisdom holds that the broad, flat pelvis of australopithecines evolved into the bowl-shaped pelvis seen in the bigger-brained Homo to allow delivery of babies with larger heads. Yet, A. sediba has a Homo-like pelvis with a broad birth canal in conjunction with a teeny brain – just 420 cubic centimeters, a third the size of our own brain. This combination shows brain expansion was not driving the metamorphosis of the pelvis in A. sediba‘s lineage.” (Sci. Am, April 2012, p. 34)

Caveats are in order. No one yet knows if A. sediba is really a human ancestor. No one knows if these early findings will hold out over time. No one knows lots of things that could make this argument moot. However . . . if this holds up, it is incredibly interesting.

As Wong says, the conventional story is that our ever-expanding brains forced an anatomical change in human females, altering the pelvis in such a way to let the big-brained babies out into the world. But what if that’s not true? What if our brains could only grow as they did if our mothers were pre-adapted, purely by accident, to allow larger-brained babies to be born?

Perhaps some other pressure – a different way of walking, a different way of fighting off a predator, even sexual selection – drove our ancestors toward a new pelvis shape. Perhaps that new shape, purely by accident, allowed for larger brains. And only later did other pressures cause the brain to evolve into its larger size.

So what? So this. Maybe (just maybe) this is another example of just how tenuous is our existence. Maybe, just maybe, this is another case that shows that there is nothing inevitable about our intelligence and our consciousness. Perhaps if our ancestors hadn’t ended up, quite by accident, with large enough hips to later on let big-brained babies out, then our brains might have remained small – or, unable to respond to the pressures for larger brains, we might have become extinct.

People are often disappointed when they find that I am not of the opinion that intelligent life is common in the universe. I just think there are too many ways to survive without human-level intelligence, and (as maybe this example shows), too many unlikely accidents that led to us. Consider that life went along quite nicely for nearly four billion years without a whiff of us. Even the Earth itself spent most of its history without human-like consciousness (or, if you prefer, human-level technology). I think it quite possible that we are, in fact, alone.

Don’t get me wrong. I’d love for ETI to exist, and I’d thrill at the discovery of a technological civilization in the stars. But the universe is not obligated to please me. We get what we get, and we make the best of it. If we are alone, that tells us something about just how precious we are. As Carl Sagan said, “If a human disagrees with you, let him live. In a hundred billion galaxies, you will not find another.”

 

I love connections. To me, they are what learning and understanding are all about. Plus they’re really cool. For instance, yesterday I learned something cool and amazing about fish and swim bladders.

OK, a little background. I was reading something about discrepant events – you know, those science demonstrations that make you go, whoa! I believe they are the key to creating disequilibrium in learners’ minds, forcing them to accommodate their world views . . . I’m losing you, aren’t I?

Anyway, while reading a list of discrepant events to discuss with learners, I came across one item that struck me as just wrong. The author was claiming that a fish’s swim bladder is a discrepant event. Most learners will think that a fish adds air to its swim bladder in order to float higher. In fact, claims the author, just the opposite is true. The fish expels air to swim higher, because the vacuum created has less mass than the air. This struck me as almost certainly wrong, so I did some research.

Sure enough, the author was mistaken. Fish do add air to the swim bladders to increase their buoyancy. But . . . how?

Think about it for a moment and it’s a great puzzle. Fish can’t have had that air inside them to begin with (unless it was compressed, and I couldn’t see how a fish could be holding compressed air in). Do they “breathe” in a bunch of air very quickly to rise? This seems impractical, as often fish need to change their buoyancy quite quickly. So what do they do? We’ll come back to it.

Have you ever been exercising and felt that painful burning in your muscles? That good ache that lets you know you’re working hard? That pain is from lactic acid. When you exercise, your muscles burn lots of glucose by combining it with oxygen, thereby releasing its stored-up energy (energy that came from the Sun via photosynthesis of the plant that made the glucose, but that’s another connection story). However, if you run low on oxygen, your muscles start to convert glucose to lactic acid. This releases energy, too, but not as efficiently as the glucose plus oxygen reaction. And the side-effect is that the lactic acid starts to make your muscles ache as it turns the tissue acidic.

Fortunately, your body has a built-in defense mechanism against lactic acid damage. When tissue starts to turn acidic, the blood feeding that tissue becomes acidic, too. And when blood becomes more acidic, hemoglobin (red blood cells) start to release more dissolved oxygen. Oxygen, of course, is exactly what your muscles are screaming for, and so everyone is happy again.

Fish, with whom we share a common ancestor (we are, in fact, highly-modified, bicycle-riding fish – apologies to Gloria Steinem), have this same physiological response, but in fish the response is even stronger. Fish blood is extremely sensitive to changes in pH, so that a little lactic acid can cause a large release of oxygen. And fish use this response in an amazing way.

Lining the fish’s swim bladder are cells that are specially adapted to produce lactic acid. When they do, instantly the blood near these cells dumps lots and lots of dissolved oxygen. Much of that oxygen goes into the bladder as gas, and that gas makes the swim bladder expand. The fish carefully controls the amount of gas going into and out of the swim bladder so that as a whole the fish remains neutrally buoyant in the water. Lactic acid as a buoyancy control! Amazing!

But it gets even better. Why do we produce lactic acid at all? Because we all evolved from bacteria that used this method to eat! Before there was much free oxygen in the atmosphere (which, after all, came from plants), all the creatures on the Earth used this non-oxygen (anaerobic) method of eating. Many bacteria still do, of course, and they can be found anywhere food is abundant but oxygen is not. It was only when the plants “poisoned” the atmosphere with this volatile, fire-supporting waste gas that evolution found the more efficient pathway of burning glucose with oxygen to release energy. We might get annoyed at this scar of evolution every time our muscles start to ache, but for fish, it’s the very scar that keeps them afloat!

And that, dear readers, is what makes life cool.

So far we’ve discovered two sources of helium in the universe. First (which came second) is the magic furnace of the stars, in which primordial hydrogen is transformed into helium via nuclear fusion, in the process lighting up the world and making peanut butter and jelly sandwiches possible. The second (which came first) is the fireball that began our universe, hot enough to cause helium to form in the first second of the universe’s existence.

But those two sources of helium don’t account for the helium we have here on Earth. Almost every bit of that helium has escaped into space by now. Why? Because it’s so light, and because it doesn’t react with anything else. With nothing to hold it here, that helium has long ago returned to the void.

You might wonder how we know that. It’s because the helium we detect today on Earth is almost entirely an isotope called helium-4. The helium produced in both the Fireball and inside stars is a mixture of helium-4 with another isotope, helium-3. We find almost no helium-3 on Earth, but there is, possibly, a nearby source that will become important as this entire story comes to a close. Stay tuned!

So why do we have helium on Earth at all? Because there’s a third source. And its been right under your feet all the time.

To find the source of that source, we need to go back to that dying star. With its hydrogen running low, that star began to collapse. That drove the temperature up, resulting in the fusion of helium into carbon. Just like hydrogen, helium can’t last forever, so eventually the star collapses again. As the temperature rises, carbon begins to fuse. It fuses with helium to make oxygen. It fuses with itself to make magnesium. It fuses with oxygen to make silicon. Oxygen fuses with helium to make neon.

All this nuclear cooking, by the way, shows why atoms with even numbers of protons are generally more common than atoms with odd numbers of protons. He (2) makes C (6). C(6) and He (2) make O (8). O(8) and He (2) make Ne (10). And so on. One exception is nitrogen (7 protons), which is actually formed in a different process that happens when a star is hot, but still contains hydrogen.

This process goes on as the star gets hotter and hotter, until the star produces iron. This is a dead end. No amount of fusion can wring energy out of the iron nucleus. Any change from iron is a net user of energy instead of a producer. That’s bad news for the star; with no energy source left, gravity takes over, and the star collapses. But just like a brick falling from a bridge, this gravitational collapse releases energy itself. In the collapse, and in the rebound that we see as a supernova explosion, vast amounts of energy are suddenly available. No longer constrained by the economics of nuclear fusion, wild collections of atoms, never before seen, are created in a moment. Among these are nearly all the gold in the universe and every bit of two very important atoms called uranium and thorium. All these atoms drifted about in space after their tumultuous birth and a few of them found themselves, quite by accident, falling into the cloud of materials that condensed to form the young planet Earth.

Uranium and thorium are rather gaudy elements. They are right at the edge of what is possible. The lighter elements are almost elegant in their balance of protons and neutrons – the most common isotope of carbon has 6 of each, oxygen 8 of each, nitrogen 7 of each, and so on. Even iron is close to being balanced, with 26 protons and 30 neutrons. But by the time you get to thorium (90 protons, 142 neutrons) and uranium (92 protons, most commonly 143 or 146 neutrons), things are wildly out of balance. In fact, these two elements have so many protons that even these wildly excessive neutrons are not enough to permanently hold the element together. Eventually, something happens.

Let’s watch one of these isotopes and see what happens. We wait, and we wait, and we wait. For thorium 232, we might wait 13 billion years or so. Or we might get lucky. The amazing thing about this process is that nobody knows when thorium will do what it does. Why? Patience, grasshopper. That answer will come.

There! The atom decayed! Shooting out of the thorium atom we spot a tiny something, traveling faster than a bullet from a gun. Where did all that energy come from? Though we haven’t discussed the details, we know the grand outline now. It’s star energy, the energy stored by that dying star, like a note in a bottle, in its final deadly explosion. You just watched a little bit of an exploding star!

http://www.youtube.com/watch?v=ItdSjJKmyDY (sorry about the music)

So what comes shooting out like a bullet? You’ve probably guessed by now. It’s helium. More specifically, it’s the nucleus of a helium atom, two protons and two neutrons. Now it just gathers a couple pieces of fluff called electrons, and we have a fully-formed helium atom, ready to fill balloons or make you talk funny. Virtually every atom of helium on Earth today was born in just this way, in the mini-explosion of a large and unstable atom inside the Earth, an atom that itself was created in the last, dying moments of an exploding star.

How cool is that?

Terry Jones wants to burn something.

I suggest The Turtle and the Universe (I hear it’s on sale at Amazon).

If you do so, Pastor Jones, I promise I won’t blow anything up. I won’t riot in the streets. I won’t even write a strongly-worded letter. Of course if I did, you’d probably burn that, too.

But why burn a children’s science book?

Well, take a look inside and the reasons become quite obvious. I claim that the Earth is 4.6 billion years old. I claim that dinosaurs and people never walked together. I lead children (innocent children!) down a path of moral decay, into a world where they believe in, no I can’t type it, you know, the e-word.

So here’s what I suggest you do, Pastor Jones. Purchase 1000 copies of my book. Toss them in a heap and light them on fire. Dance around the bonfire and celebrate the souls you’ve just rescued. It’ll make you feel better. Do it for the children!

And, on the odd chance that Pastor Jones isn’t a regular reader of Turtle Universe (unlikely as that may be), any of you loyal readers out there (both of you) are encouraged to get the ball rolling by purchasing your own copy of The Turtle and the Universe and having it shipped directly to:

Dove World Outreach Center

5805 NW 37th St
Gainesville, FL 32653

If it works out, just turn the other cheek. It’ll all be ok, really it will.

I’ve written before about Cloverfield Pond. On a recent visit there, I had an odd thought. What would happen if I just walked into the pond and sat down?

Well, the water’s probably not more than a foot or two deep, maybe three in the middle, so I’d probably still be able to breathe. But eventually, if I sat there long enough and didn’t defend myself, I’d be eaten. Nature is full of beauty and mystery and wonder, but it’s also hungry. And, not to sound egotistical, but I taste good.

What does that mean? It means that my body is chock full of low entropy stuff that other creatures crave. They can use my low-entropy ingredients to extract energy and/or build their own low-entropy bodies. Wherever there’s a resource, some creature will exploit that resource. And resource means low entropy.

But why should I be build of such tasty stuff? It’s not just me, of course. It’s you, too. It’s all of us. In order to be alive, we have to be made of low-entropy materials. That’s part of what being alive is. How’d we get that way?

Well, we ate other low-entropy individuals. Probably not other people, but certainly plants, and (if you’re like me) other animals, too (vegetarians taste better). We took those low-entropy materials, extracted the usable energy, utilized the most useful structures such as proteins, and, um, got rid of the rest. All living things are engines for extracting what they need from low-entropy materials, then returning high-entropy waste to the environment.

Plants are the crucial link, of course. They grab low-entropy sunlight and transform high-entropy materials (carbon dioxide and water vapor) into low-entropy materials (sugar). Everything else depends on their ability to do this amazing transformation trick. But notice how they do it. They capture very high-entropy sunlight and, overall, return lower-entropy ingredients to the environment.

This isn’t a criticism of plants; rocks would do much worse. A rock just absorbs low-entropy sunlight and then just radiates back much higher entropy radiation, without producing anything useful in the process.

But why, we have to ask, does sunlight have such low entropy? Because it was produced in a low-entropy environment, the Sun. There, low-entropy hydrogen is fused into higher-entropy helium, changing mass into light energy.

Let’s keep following the reductionist chain. Why is hydrogen lower entropy than helium? Because in reacting, hydrogen must fire off positrons and neutrinos, all of which carry away energy. The resulting helium atom has a mass just low enough to match the lost energy.

But where did the hydrogen come from? Hydrogen came originally from the Big Bang itself. Here, finally we reach the crucial mystery. The Big Bang began as an incredibly tiny dot of hugely low entropy (extreme high order). Ever since that event, the overall entropy of the universe has been increasing. Though, fortunately for us, overall entropy is a subtle concept.

Occasionally, gravity may pull a star together, lowering the local entropy. But because huge amounts of heat are released, the overall entropy still goes up. Even more rarely, the low-entropy light of the star may support life on a nearby world. Like stars, living things reduce their own local entropy, always at the cost of increasing the entropy of their surroundings (by, for instance, eating their neighbors, then releasing the waste).

One of those living things, me, has been increasing the entropy of his surroundings for over four decades now. But I know it can’t last forever, because I taste so good.

And so do you. The next time you go to the zoo and notice the tiger or polar bear eying you hungrily, the next time you get bitten by a mosquito or even just catch a cold, remember why these creatures are after you. You taste good because of the amazing order that existed just before the Big Bang. Yum!

I’m not sure I buy Davies’ argument from the previous post. There’s lots of potential big steps that might have taken less time than anticipated. Why the origin of life? Why not the origin of eukaryotic cells, multicellular animals, life on land, big brains? Why did those things all take a long time? The most straightforward answer is that those things are hard. If life’s origin is hard, too, then why didn’t it take at least a while to start here?

Even so, I agree with Davies (and Ward and Brownlee), about complex life, and intelligent life. I think it is very rare, so rare that we might be the only one.

I’m persuaded by Fermi’s Paradox: “where are they?” We’re talking here about intelligent life that, at least in some cases, must be many millions, even billions, of years old. If they were there, I believe we’d know it. Maybe not every intelligence would make their presence known, but it only takes one. It’s an old, old universe, and we just got here. Where is everybody else?

We can imagine a universe in which extraterrestrial intelligent life is obvious. We’d look up in the sky, and we’d know. Clearly we don’t live in that kind of universe. There are two potential reasons. One, they’re not there. Two, they’re there, but no one’s doing anything we’d recognize across the light years. Not one? In millions, even billions, of years? Really?

You can, of course, think of lots of scenarios explaining why we seem to be alone even if we’re not. But they are all special pleading. The most straightforward explanation for us seeming to be alone is that we are.

Some people might find this depressing, and I admit, I’d love for us to discover other intelligences. Just a single discovery could change everything tomorrow. I hope it happens. Assuming it doesn’t, though, I’m not so sad about the alternative. If we really are alone, then we have a huge universe that is ours and ours alone. We are the eyes and ears of that universe. Let’s see what we can learn.

I just finished “The Eerie Silence” by Paul Davies. Davies is deeply involved with SETI, and so took some time to speculate on the possibility of extraterrestrial intelligence.

It’s a subject I find fascinating, though I recognize that it’s all speculation. Still, it’s fun to think about.

I’ve been influenced by Peter Ward and David Brownlee, who wrote an amazing book called Rare Earth and another called The Life and Death of Planet Earth, and I’ve very much adopted their argument.

The argument goes like this: life itself may be quite common in the universe. After all, life seems to have appeared on our planet as soon as it possibly could have. It would be quite a coincidence if life began here so quickly, but then never appeared anywhere else.

But Davies points out a flaw in this argument. We are not a random sample, but a very special circumstance. We are a place where life has gone from single cells to complexity and intelligence. It took a very, very long time to get there – most of the time that the Earth will be inhabitable. We humans just barely made it, sneaking in under the wire before, in just 1 billion more years, the Sun gets so hot that it sterilizes the planet.

If that is typical, then it is no surprise that we happen to live on a planet where life started quickly. If it hadn’t, if it had taken billions of years instead of millions or less for life to form, there wouldn’t have been time for humans to develop. In the “space” including all those planets that have life, only those on which life started quickly is there any chance of finding intelligence. Naturally, since we’re here to ask the question, we live on one of those lucky early-life worlds.

It’s an interesting argument, and I’m still thinking about it. I think I’ll write about it again.

My first book, called The Turtle and the Universe, was published by Prometheus Books in July 2008. You can read about it by clicking on the link above.
My second book, Atoms and Eve, is available as an e-book at Barnes and Noble. Click the link above. You can download the free nook e-reader by clicking the link below.
November 2017
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A blog by Stephen Whitt

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