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Our future, our universe, and other weighty topics

Monday, March 26, 2018

The Organization Explosions They Can't Explain

Last night on the National Geographic channel there was a science documentary discussing the origin of life. It was the typical misleading treatment of this topic I expect to see on a TV show or a mainstream source. There was the usual vastly overconfident talk suggesting scientists may be on the brink of solving the problem of life's origin, an entirely unfounded claim we have been hearing for 70 years. We also heard a scientist in front of a hot spring or hydrothermal vent saying, “This is where chemistry turns into biology.” No, it isn't. There could only be a case of chemistry turning into biology if chemicals were to turn into a living thing, something that hasn't happened on our planet for at least three billion years, in either nature or a laboratory. Chemistry does not turn into biology in hot springs or hydrothermal vents.  As a recent scientific paper notes, "Independent abiogenesis on the cosmologically diminutive scale of oceans, lakes or hydrothermal vents remains a hypothesis with no empirical support."

The origin of life is a case of an organization explosion. The origin of even the simplest life seems to require a fantastically improbable burst of organization. Protein molecules have to be just-right to be functional. It has been calculated that something like 1070 random trials would be needed for a functional protein molecule to appear, and many such protein molecules are needed for life to get started. And so much more is also needed: cells, self-replicating molecules, a genetic code that is an elaborate system of symbolic representations, and also some fantastically improbable luck in regard to homochirality. Scientists have no plausible explanation for this organization explosion, nor do they have a decent explanation for another organization explosion: the Cambrian Explosion.

When we examine the fossil record, we don't see fossils appearing in larger and larger sizes, at an even rate of progression between 3 billion years ago and 100 million years ago. Instead, we see very little fossil evidence of life prior to the Cambrian era about 520 million years ago. But during the Cambrian era there is a sudden surge of fossils in the fossil record. This sudden blossoming of life during the Cambrian era is known as the Cambrian Explosion.

The major groupings of life are called phyla. There are about 35 animal phyla, and almost all of these phyla appeared during the Cambrian era. There is not a single animal phylum that has arisen since about the time of the Cambrian era, which lasted from about 540 million years ago to 485 million years ago. As one research paper states, “The youngest animal phylum is about 500 million-year-old.” This highly technical document states that Bryozoans are the youngest phylum of animal. The document states:

Bryozoans, or moss animals, make their first appearance in the fossil record about 490 million years ago. All other phyla had appeared by about 510 million years.

This creates quite a problem for Darwinian theory, as it is not what such a theory predicts. According to Darwinian ideas, what we should have seen is more and more phyla appearing as time progressed, as more and more branches appeared in a tree of life, like the tree of life that appeared as an illustration in The Origin of Species. In fact, Darwin said in The Origin of Species that the Cambrian Explosion “may be truly urged as a valid argument against the views here entertained.”

We don't know how many animal phyla originated in the Cambrian Explosion, and estimates vary between 30 and 100. The graph below assumes an intermediate estimate of 50. A graph like this is startling, because it shows the origin of animal phyla in a single blip.

cambrian explosion

There have been various attempts to explain how the Cambrian Explosion could have occurred. One such attempt is the book In the Blink of an Eye by biologist Andrew Parker. The author's theory is summarized on the dusk jacket of the book:

Parker's astounding explanation is that it was the development of vision in primitive animals that caused the explosion. Precambrian creatures were unable to see, making it difficult to find friend or foe. With the evolution of the eye, the size, shape, color, and behavior of animals was suddenly revealed. Once the lights were “turned on,” there was enormous pressure to evolve hard external parts as defenses and grasping limbs to grab prey. The animal kingdom exploded into life, and the country of the blind became a teeming mass of hunters and hunted, all scrambling for their place on the evolutionary tree.

The book calls this theory the “light switch” theory. What is this “pressure” referred to in this quote? It is what Parker calls “selection pressure.” The concept of selection pressure is reasonably used when talking about microevolution, changes in a population that result simply from a state where some particular trait already present in the population is either favored or disfavored by the environment.

Here is an example. Imagine a population of 500 dogs is introduced in the wild to a very cold island in upper Canada. Some of the dogs may have short fur, and others may have thick fur like the Samoyed breed. In such a situation, you could say there is selection pressure that might cause the dogs with thick fur to become more common in the population over the next few generations (because the short-haired dogs might tend to freeze to death). This is an example of microevolution, which does not involve any new complex biological innovations. All of the examples in the wikipedia.org article on “evolutionary pressure” (the same as selection pressure) are mere examples of microevolution.

But Parker has hijacked the term “selection pressure,” which is reasonable when talking about microevolution, and he is using it to try to explain sudden cases of biological innovation, what is called macroevolution. This is illegitimate. In no sense can we explain dramatic macroscopic innovations by using the phrase “selection pressure.”

Let us consider the Darwinian account of how evolution occurs. We are told that new biological innovations are caused by lucky random mutations and natural selection. The idea is that over the eons there very rarely occur fortunate random mutations. We are told that natural selection causes favorable random mutations to accumulate, and that this results in useful new adaptions.

Such a Darwinian process will be at the mercy of how often these rare lucky mutations occur. Such a rate will not be sped up when there is a need for some particular innovation. If a biological innovation requires many parts before it can be useful – which is certainly the case for a vision system, hard shells, and grasping limbs – then there will be no natural selection at all until the innovation has reached a functional threshold, which requires quite a few parts arranged in a way that achieves a functional coherence.

Using the term “selection pressure” to try to explain such an innovation of macroevolution is nonsensical. There would be no natural selection at all until the innovation had become largely functional. And when there's no natural selection going on, there can be no selection pressure. It is absurd to use the word “pressure” to try to explain the natural origin of useful parts and their arrangement into functionally coherent systems. It would be just as absurd to say that if you are freezing in the woods, there will be a “habitation pressure” that will cause falling trees to form into a log cabin for your convenience.

For example, suppose there's a species that does not have wings, and is often preyed on by some predator. It is absurd to say that there is then a selection pressure pushing such an organism to turn into a flying organism that can escape the predator. Until the organism were to develop functional wings, there would no natural selection going on favoring wings. And when there's no natural selection favoring something, there cannot be selection pressure.

Parker's magic-wand phantasmagorical thinking about “selection pressure” is shown on page 6 of his book, where he says, without providing an example, “The introduction of a new food source may lead to the evolution of new mouthparts and limbs for movement.” So if you're an animal that doesn't have a mouth or legs, and some other mobile animal starts to appear in your area, one that might be nice for you to eat, then evolution conveniently provides your species with a mouth and legs, like some Fairy Godmother providing Cinderella with just what she needed for the Prince's ball? That's hilarious.

In reality, Darwinian evolution will always be at the mercy of random mutations that will not cooperate based on needs, and which will always be fantastically unlikely to provide a species with new innovations that it might find useful. This is because virtually all random mutations are neutral or harmful, and it is fantastically unlikely that random mutations would conveniently occur in a way allowing parts to fit together, so that functional coherence was achieved. The need for some biological innovation would cause no change at all in the rate at which favorable random mutations would occur. Such favorable random mutations would be just as fantastically unlikely to occur when a species needed something as when the species didn't need anything. Similarly, there is no relation between your financial needs and the likelihood of you winning a million dollars by playing roulette at Las Vegas.

Below are some of the innovations appearing suddenly in the Cambrian explosion:

  1. vision, appearing in species such as trilobytes;
  2. various phyla that did not have protective shells;
  3. body parts allowing moving about and attacking other organisms;
  4. protective shells
You don't explain the first three of these under any “the lights turned on, so animals needed to protect themselves” idea, as it doesn't explain the first three things. Nor does it work to explain the appearance of protective shells by evoking Darwinian natural selection. Let us imagine the gradual evolution of a protective shell around the internal organs of some species like a primitive trilobyte. The first stages in such a protective shell would offer no benefit, because the organism's body would still be a mostly unprotected area that a predator could attack, like some shark munching on a swimmer who only had his wrists protected by steel bands. So there would be no natural selection benefit for the early stages of such an innovation. This is the same “non-functional intermediates” problem, which in Darwin's time was called the problem of incipient stages.

The problem of explaining the Cambrian Explosion is the problem of explaining the abrupt appearance of a wide variety of sudden biological innovations, including vision, which there is no fossil record of before the Cambrian Explosion. Parker cheats on such a task by offering an explanation that starts out with vision appearing, and then tries to use that to explain the other innovations. That's a cheat because his “light switch” theory doesn't explain the hardest part of the Cambrian Explosion, explaining the origin of vision. 

The problem of the origin of vision is constantly minimized by evolutionary biologists, who try to reduce it to only being the problem of an eye developing. But there are 4 parts in even the most elementary vision system:
  1. an eye
  2. an optic nerve
  3. extremely fine-tuned light-capturing proteins, fantastically unlikely to appear by random mutations
  4. very complex brain changes needed to interpret visual input
So here we have a classic case of the problem that intermediates or incipient stages would be nonfunctional. For example, it would do a species no good if it had only a primitive eye but not the proteins needed to capture light, or only those proteins but not the primitive eye.

Parker's explanation for vision's origin is as featherweight as a photon. His explanation is basically: because there was a little more sunlight, vision appeared. On page 291 to 292 Parker states:

The first eye must have evolved in response to an increase in sunlight...And indeed the geologists have revealed an increase in sunlight levels precisely at the very end of the Precambrian.

He provides no reference for this claim, which is not true in any substantive sense. There is no geological way to tell how much sunlight there was 530 million years ago, and scientists in general assume that the sun does not suddenly change its output. The scientific paper here has a graph that shows an estimate of solar radiation during the past billion years. We see no sudden increase at the time of the Cambrian Explosion about 530 million years ago.

The basic idea behind Parker's “light switch” theory in his In the Blink of an Eye book is a kind of “Fairy Godmother” concept of evolution. It's the idea that when species need something, evolution rather quickly provides them with wonderful new innovations, “in the blink of an eye,” like the Fairy Godmother providing Cinderella with the wonderful innovations she needed to go to the Prince's ball (or like the female character in I Dream of Jeannie blinking something into existence to benefit her astronaut master). Such a chimerical description is very much at odds with standard claims that evolution is driven by mere random mutations and natural selection. The rate at which incredibly unlikely favorable random mutations occur will have no relation at all to the needs of some species, and it should always be fantastically improbable that random mutations should occur in an organized way that conveniently matched the needs of some species. 

Another lame explanation of the Cambrian Explosion involves saying that there was an increase in oxygen that allowed it. But you don't explain a fantastically improbable thing by merely mentioning that a prerequisite for it recently appeared. That's as fallacious as Bob's reasoning in the exchange below, which takes place in Joe's backyard.

Joe: How do you like my house of cards?
Bob: You must have made that by just throwing a deck of cards into the air.
Joe: You're crazy! That would never work. 
Bob: But I have an explanation for how it happened: it's that today is a nice calm day. You never could have made that house of cards yesterday by throwing the deck of cards into the air, because yesterday it was too windy for that to work. 

Bob has here committed the fallacy of trying to explain a fantastically improbable event by merely mentioning that a prerequisite for it occurred.

There's one other explanation I've read for the Cambrian Explosion. It's that we observe it because the Cambrian Explosion suddenly started making fossils that are big enough and hard enough for us to observe 500 million years later. That explanation is as lame as the young man's reasoning in the exchange below.

Old man: I've never seen anything very strange,  except that 50 years ago I suddenly saw 40 huge monsters appear in a field. 
Young man: The explanation is obvious. You saw them that day because they were so big. If they were just tiny monsters, you wouldn't have noticed them.

This type of explanation explains nothing. 

There is also the rather laughable explanation suggested by one  researcher, in an article entitled, "Cancer tumors could help unravel the Cambrian explosion."  Talk about grasping at straws. Cancer is a disorganized cell growth, and such a thing does nothing to explain the incredible organization burst that occurs when a new phylum originates. In the article the author claims to have advanced a "new theory," but the scattered observations in the article never amount to a coherent hypothesis. 

A more substantive idea is advanced in this paper, which tries to suggest that earthly evolution has been supercharged by comet bombardments carrying genetic material from beyond our planet. I'm rather skeptical that such an idea could help much with the Cambrian Explosion problem, but perhaps it could help plug other holes in the standard story of earthly life's evolution. The authors state the following, making an interesting comparison between prevailing Darwinian theory and the discarded theory of Ptolemaic epicycles:

In a final reckoning it would have to be admitted that ultimately all of evolution has been controlled and continues to be controlled by space-borne organisms, microbes and viruses. It is important that we not allow Science to be stifled by a reign of dogmatic authority that strives to restrict its progress along narrow conservative lines. The current situation is strikingly reminiscent of the Middle Ages in Europe – Ptolemaic epicycles that delayed the acceptance of a Sun-centred planetary system for over a century.

A question raised by their idea is: if you're going to imagine extraterrestrial life contributing to earthly evolution, then why not just try to explain the Cambrian Explosion by imagining a spaceship that came here and dropped off organisms specifically designed to live here, as I speculated in this post?

Postscript: One of the authors of a scientific study confirms that the appearance of the first animals (which the author dates to 541 million years ago) involved an information explosion. The author states this:

We discovered the first animal had an exceptional number of novel genes, four times more than other ancestors. This means the evolution of animals was driven by a burst of new genes not seen in the evolution of their unicellular ancestors.

The scientific paper gives specific numbers of new genes that appeared when specific groups of animals originated. For example, it lists 1580 novel genes needed for Bilateria to originate, 1201 novel genes needed for Planulozoa to originate, and 1189 novel genes needed for Metazoa to originate. 

Interestingly, the New York Times covers this story with a headline "The Very First Animal Appeared Amid an Explosion of DNA," which sounds like my phrase "information explosion." Meanwhile panspermia.org refers to these novel genes by saying,"What we find remarkable is that neither the genes that apparently predate animals, nor the novel ones noticed now... have any discernable darwinian provenance," meaning they are unexplained under Darwinian theory. 

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