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Friday, May 27, 2011

Book Review - God- or Gorilla?, Chapter 16

This entry is part of a series. For a bit of an introduction and an index of all entries in the series, go here.

God or Gorilla PicThis installment covers Chapter 16, Bateson - A Brilliant Light.

Knowing what we now know about genetics, it's hard to imagine a time when people would have thought that it cast doubt on evolution. Here, McCann was quoting one of the founders of genetics, William Bateson.

"If we cannot see how a fowl by its egg and its sperm gives rise to a chicken or how a sweet pea from its ovule or its pollen grain produces another sweet pea we at least can watch the system by which the differences between the various kinds of fowl or between the various kinds of sweet pea are distributed among the offspring. . . . Until Mendel began this analysis nothing but the vaguest answers to such a question had been attempted. THE EXISTENCE OF ANY ORDERLY SYSTEM OF DESCENT (denied by Haeckel) WAS NEVER EVEN SUSPECTED." (McCann 205-206)

It's a bit silly to say that "the existence of any orderly system of descent was never even suspected". Of course an orderly system was expected. It's pretty obvious that dogs don't give birth to cats. The difference is that before Mendel, most scientists suspected blending inheritance. Mendel discovered that whatever it was that controlled inheritance was discreet. We now know that it's our genes, coded in DNA.

Here's another case of human exceptionalism.

Alas, by what violence of imagination are we to trace man's inheritance of the art faculty, the metaphysical faculty, the faculty of wit and humor, the faculty of scientific investigation, to the seed of an ape or of any other lower animal, without the intervention of God? (McCann 206)

I'm not going to quote de Waal yet again, but here's a link to his article in the New York Times.

We're probably smarter than any other animals. We're certainly more technological, and are the only animals that practice science. But let's not get too conceited over it. If we were cheetahs, we'd scoff at how slow all the other animals were. Or if we were blue whales, at how small they were. Or if we were swifts, at how land-bound they were. For any given trait, some species is going to be the best. But it's just one trait. Plus, it may not be the best by much. Just like a pronghorn is nearly as fast as a cheetah, dolphins and elephants appear to be nearly as smart as us, just not with a technological bent. The other great apes are all pretty smart, too.

Although McCann sees humans as much, much higher than 'lower' animals, he still apparently doesn't have a very high regard for our species.

We are living in an age of intellectual pride which takes as little heed of its futile vanities as of its paradoxical pursuit of gross humiliations. Few of us stop to consider that it was not the brain of the average fallen man that has given us the printing press, the cotton gin, the smelter and the anvil, the engine and the dynamo, the telegraph and the telephone, the trans-Atlantic liner and the aeroplane, the microscope and the telescope. We employ these majestic discoveries as if they were our own; as if they had not been given to us by a comparatively few geniuses standing as solitary luminaries above and beyond the average mass of fallen humanity. The poet Longfellow must have had some such thought in mind when, referring to the Mother of Christ, he penned the line, "Our tainted nature's solitary boast." (McCann 208-209)

Maybe things were different in McCann's time, but it's certainly not the scientific community that conflates evolution and abiogenesis these days.

By this time the student through his examination of facts and contradictions has probably arrived at the conclusion that the whole doctrine of evolution has been directed into lanes of confusion and darkness by reason of its vain assumption that its object was to explain the origin of life upon this planet. To attain progress along this deliberately selected route it was forced to espouse the assumption of a monophyletic evolution of the whole kingdom of organic life from a single cell which sprang into existence through some never repeated phenomenon of spontaneous generation. (McCann 210-211)

In discussions such as this, though, the distinction between evolution and abiogenesis is a bit of a moot point - there are few people who accept evolution who wouldn't also accept abiogenesis. However, 'monophyletic evolution' was not an initial assumption. It was the conclusion after studying the evidence.

You can see the precursors of the creationist micro- vs. macro-evolution canard.

The net result of his [Standfuss - jrl] extraordinary experiments took the shape of an opinion that the only really important variations of species are those modifications caused by definite external influences, which modifications, described as "adaptive variations" are transmitted to succeeding generations. (McCann 212)

It is common nowadays to hear creationists say that 'microevolution' occurs, but not 'macroevolution'. These are in fact real terms, but they're misused by creationists. To quote from Talk Origin's Index to Creationist Claims, "Microevolution is defined as the change of allele frequencies (that is, genetic variation...) within a population... Macroevolution is defined as evolutionary change at the species level or higher, that is, the formation of new species, new genera, and so forth." Many creationists actually do accept that macroevolution as properly defined does happen (it's the only way to explain the Noah's Ark story), and instead take macroevolution to mean some unspecified big change. Still, where's the stop sign? If you have enough small changes over many generations, what's to stop that resulting in a big change? The journey of a thousand miles begins with a single step (and sometimes ends badly).

Despite all the talk of bad science, here McCann gets down to the real reason he doubts evolution.

Polyphyletic evolution, instead of getting back to an accident resulting in a single stock from which the myriads of modern living creatures in the animal and vegetable kingdoms have descended, begins with numerous stocks expressly created by God and controlled as to their variations by the operation of fixed laws revealing plan and purpose. (McCann 212)

It really is religion that makes McCann reject evolution.

Proceed to Chapter 17

Wednesday, May 25, 2011

Gamera Human Powered Helicopter

University of Maryland's Gamera Human Powered HelicopterFrom time to time, I actually read the newsletter from the engineering department from my alma mater, the University of Maryland. The latest had an interesting story. Some students built a human powered helicopter, and managed to get it airborne (around 6" off the ground for just a few seconds, but still, it took off under its own power).

Human powered flight in fixed wing airplanes, if not exactly common place, has been accomplished numerous times by now. The record holder is the MIT Daedalus, which flew 71.5 miles from the island of Crete to the island of Santorini, staying aloft for 3 hours and 54 minutes. A flight that long is more than just a hop, but human powered flight is still pretty demanding. It took an Olympic cyclist to pilot that aircraft, and the structure was so optimized (the plane itself only weighed 69 lbs), that it couldn't handle the winds in Santorini and was blown apart before the pilot landed (he did escape unharmed). Other notable human powered airplanes include Southampton University's Man Powered Aircraft (the first human powered aircraft to take off under its own power in 1961), the Gossamer Condor (which won the first Kremer prize in 1977 by flying a designated course), the Gossamer Albatross (which crossed the English Channel in 1979), and the Musculair 1 (the first human powered aircraft to carry a passenger in 1984).

But if fixed wing airplanes are a challenge, human powered helicopters are next to impossible. I've only heard of 3 that have actually managed to lift off - California Polytechnic State University's Da Vinci III, which flew for 7.1 seconds at a height of around 8" back in 1989, Nihon Aero Student Group's Yuri I, which flew for 24 seconds and reached 27.5" in 1994, and now University of Maryland's Gamera, which flew for 10.8 seconds at around 6". Although certainly impressive technically, none of those results are very awe inspiring. It just goes to show how thin air really is, and why flight is such a challenge that humans weren't able to conquer until last century.

There's an Official Gamera Website where you can see pictures of the aircraft and read more about it. There's also a Wikipedia entry. To get a better idea of the scale of the aircraft, you really should watch the video of it flying (the flight starts at around 3 minutes into the video).

From the above websites, I gathered the following data. The empty weight of the aircraft was only 101 lbs, and with the pilot included the gross weight was only 208 lbs. The helicopter had 4 rotors, each with a 42' diameter.

A metric that rotorcraft engineers like to use is disc loading. You divide the weight of the aircraft by the disc area of the rotors. This is all to do with efficiency - the lower the disc loading, the more efficient the rotor can be. When you calculate disc loading for this aircraft, you get 0.0375 lb/ft². That's incredibly low. For comparison, the Robinson R-22, a lightweight helicopter with a relatively low disc loading itself, has a gross weight of 1370 lbs and a rotor diameter of 25'-2", giving a disc loading of 2.75 lb/ft². Gamera's disc loading is more than 70x lower than the R-22's! For another comparison, the V-22 Osprey has a relatively high disc loading of 26.7 lb/ft² (part of the reason why it will never do as good as a pure helicopter in hover), 712x higher than the Gamera.

I can't help but put up a picture of da Vinci's helicopter concept here. Everyone knows that his concept wouldn't work, but I don't think most people realize just how far from a workable design it really is. You can't be too hard on da Vinci given the state of aerodynamic knowledge in his time, but compare this to the Gamera.

da Vinci Helicopter Concept

On a less technical note, Maryland's human powered helicopter was the first to be powered by a woman, 24 year old biology student, Judy Wexler. I wonder if they chose a woman just to be the first, or if it was more to do with improved power to weight ratio (she only weighs 107 lbs).

So, my hat's off to the students at the University of Maryland who built this aircraft. It was an incredible technical accomplishment. I gather that they're going to attempt more flights and try to claim the Sikorsky Prize. I wish them luck.

More Info:

Friday, May 20, 2011

Book Review - God- or Gorilla?, Chapter 15

This entry is part of a series. For a bit of an introduction and an index of all entries in the series, go here.

God or Gorilla PicThis installment covers Chapter 15, Chromosomes and Genes.

Darwin used artificial selection (breeding) as an analogy to natural selection. Here, McCann tried to cast doubt on that analogy.

Artificial selection selects exceptional, most widely divergent characters which appear only in a few individuals, whereas natural selection is a selection of slight differences appearing simultaneously in many individuals. Artificial selection often leads to morbid or exaggerated development, to a sickly disposition, to an undermining of the whole constitution, whereas natural selection effects no injury to the whole constitution but on the contrary strengthens and betters it. Artificial selection results in lack of stability. Natural selection remains constant.

"In the light of this truth," says Morgan ("Evolution and Adaptation," 1903) "the relation between the two selective theories may appear quite different from the interpretation that Darwin gives it." (McCann 195)

Artificial selection is still a very good analogy to natural selection. In fact, they're pretty much the same thing. It's just that the selection pressures can so heavily favor single traits in artificial selection, or become extremely relaxed for traits that domestic animals no longer need. For example, let's look at modern chickens. They're extremely exaggerated compared to wild chickens. They're little more than meat factories with the bare minimum of life support to grow that meat (more info). But selection explains exactly why they got that way. Farmers chose the most muscle bound chickens to breed, so they created the most offspring. Scrawnier chickens were sent straight to the slaughterhouse without a chance to make any baby chicks. Farmers have just become a new selection pressure compared to what wild chickens see.

I don't want to criticize McCann too much for misunderstanding genetics, since it was still a fairly young science in his time, but here is a perfect case of what the modern synthesis would bring to the theory of evolution.

Here the biometrician and the Mendelist part company. The biometrician says: "Selection is the process of accumulating infinitesimal differences through gigantic periods of time." The Mendelist says: "Selection is a process of combining and sorting out genes." The biometrician says: "Selection is creative, actually producing new characters." The Mendelist says: "Selection merely assorts, and such effects of variation as are sometimes said to be found are merely due to new combinations of characters that were already present." (McCann 196)

When McCann quotes an actual scientist immediately following the above paragraph, he can make a good point.

De Vries himself says ("Darwin and Modern Science," p. 70): "Natural selection acts as a sieve; it does not single out the best variations but it simply destroys the larger number of those which are from some cause or another, unfit for their present environment. In this way it keeps the strains up to the required standard, and in special circumstances may even improve them." (McCann 197)

We now know that both points of view presented above are right. Random mutation is the ultimate source of the genetic variation in a population, and mutation occurs all the time. Current estimates for human mutation rates are around 100 mutations per individual. Obviously, most of those are neutral, but some will be advantageous or deleterious, and even that will depend on environment.

So, thanks to mutation, you have populations of organisms with quite a bit of genetic diversity. Natural selection acts on that existing diversity - it doesn't create new characters. Go back to my hypothetical population from a previous entry, where an environmental change favors animals that can browse from the tops of trees. Natural selection never creates an individual with a longer neck. Random mutations create animals with longer and shorter necks than their parents, and natural selection describes how those animals with the longer necks survive and reproduce more. After many generations, the population will be composed of animals with much longer necks than the founding population, but it was random mutation that created the longer necks in each generation.

To anyone who's spent any time following creationism, the argument that genetic mutation can only cause the loss of information, and not create anything new, is a familiar argument. After reading McCann, I now realize that this argument is nearly as old as genetics itself.

But science is not looking for losses along the path of evolution. On the contrary science insists she is looking for gains, additions.

It is for this reason that so many scientists are reluctant to admit that characters which look like additions in domesticated or cultivated forms are really due to the LOSS of something which in the past has prevented the appearance of the hidden factor. (McCann 197-198)

I'll once again use Richard Lenski's experiment, where e. coli developed mutations that gave them the ability to digest a new food source (citrate), as an example of how random mutations can result in new functions. I'll also link to an article by Richard Dawkins, The Information Challenge, which explains the processes of how information can be added to the genome.

With the way so many people today use the term 'Darwinism' synonymously with evolution, it's interesting to see it used in a slightly different (and probably more accurate) context.

"Klebs, the eminent plant physiologist," says Kellogg, "keenly criticizes the mutation theory. Copeland finds in the mutations of De Vries nothing radically different either in character or behavior from the Darwinian fluctuating variations." (See "Darwinism Today," 1907, pp. 372-373). Having abandoned Darwin and come to De Vries, there would thus seem to be a desire to return to Darwin. On this point Kellogg is clear and emphatic. He says, under the caption, "The Deathbed of Darwinism," in the introduction to "Darwinism Today," 1907: "... Numerous books and papers are appearing now in such numbers and from such a variety of reputable sources as to reveal the existence among biologists and philosophers of a widespread belief in the marked weakening, at least, if not serious indisposition of Darwinism. A few of these books and papers from scientific sources even suggest that their writers see shadows of a deathbed. (McCann 199)

So, Darwinism here isn't simply evolution. It's contrasting Darwin's evolutionary theories with De Vries' evolutionary theories.

With how much we take for granted our knowledge of genetics today, it's interesting to see this.

The remarkable fact has now been established that every species of plant or animal has a fixed and characteristic number of chromosomes. In many of the lower animals the number of chromosomes to the cell has been determined positively. With respect to man the number is now thought to be twenty-four. Wieman (1917) asserts that the number in both negro and white spermatogonia is twenty-four, thereby agreeing with Duesberg's (1906) count. (McCann 199-200)

The vast majority of people have 24 chromosomes. However, the number's not exactly fixed. Mutations involving fusions are so common that they have their own name, Robertsonian Translocations. Those people only have 23 chromosomes, and they get along just fine, though their children carry a higher risk of Down Syndrome and other similar disorders.

If only McCann could have actually seen the research he was wondering about.

At this writing, 1921, no scientist may foretell what a contrasted examination of the chromosomes of the chimpanzee, gorilla, orang, gibbon and man will reveal, yet the old dogmatic certitude of the evolutionists, who have heeded none of the bewildering complexities involved in this study, persists, as if it were indeed a thing upon which the freakish Trinil Ape-Man, Piltdown Ape-Man and Neanderthal Ape-Man might look with profound contempt. (McCann 201)

There's a very good comment in Pharyngula, that I often link to in these discussions (I have a local copy on this site it's so good). It discusses the very thing McCann mentioned - "a contrasted examination of the chromosomes of the chimpanzee, gorilla, orang, gibbon and man". We're related. Chimpanzess and bonobos are the most closely related of the great apes, and are next most closely related to humans. Our DNA is more similar to a chimp or bonobo than is that of a gorilla or orangutan.

We do have a different number of chromosomes than the other great apes, but when you look at our chromosome 2, you find telomeres and centromeres exactly where you'd expect if two chromosomes had fused together in one of our ancestors. And when you compare our chromosome 2 side by side with chromosomes 2p and 2q from the other great apes, you see marked similarities.

Comparison of Human & Ape Chromosomes

There's no doubt that all of us great apes are related.

Proceed to Chapter 16

Tuesday, May 17, 2011

Book Review - All My Friends Are Dead

I just recently bought* a rather silly book that I happen to like quite a bit, All My Friends Are Dead. It's described as "either the saddest funny book or the funniest sad book you'll ever read." At only 96 pages long, with only a handful of words per page, it can be read cover to cover in less than a quarter of an hour. It's pretty funny, in an off beat way. I've handed it to nearly everyone who's come to the house since I bought it, and so far everyone's laughed out loud while reading it (not necessarily at every joke, but at quite a few). If you want a taste for what's inside, the book's website shares a few of the pages:

Official Website for All My Frieds are Dead

I definitely recommend this book.

* On a trip to the mall with my daughter's girl scout troop, I didn't feel like sticking around Claire's with the girls, so I walked to the store across from it, Spencers, and took a quick look through the books (don't worry - my wife stayed with the girls). I was originally looking to see if they had any Chuck Norris books as a gift to a friend who likes those jokes, when I saw All My Friends Are Dead. I read it completely there in the store, but wasn't sure if I wanted to pay $10 for such a short book, so I put it back, and figured it was about time to catch back up with the troop. Well, the jokes stuck with me, so the next time I was at the mall, I decided to actually buy it. As described above, I've been able to share it with quite a few people, so I think it was worth it.

Friday, May 13, 2011

Book Review - God- or Gorilla?, Chapter 14

This entry is part of a series. For a bit of an introduction and an index of all entries in the series, go here.

God or Gorilla PicThis installment covers Chapter 14, Complications.

Yet again, McCann shows his misunderstanding in thinking of evolution as a ladder. First, he quotes a scientist discussing fossil whales and their teeth, and then goes on to give his interpretation.

Sir J. W. Dawson ("Chain of Life," p. 222), says: "The oldest of the whales are in their dentition more perfect than any of their successors, since their teeth are each implanted by two roots, and have serrated crowns, like those of the seals. The great Eocene whales of the South Atlantic which have these characters attained the length of seventy feet and are undoubtedly the first of the whales in rank as well as in time. This is, perhaps, one of the most difficult facts to explain on the theory of evolution."

They start you off back there with a little squirrel-like creature when the whale was a mammal seventy feet in length, more perfect according to the bewilderment of evolution than it is today, and they ask you to believe that the little squirrel-like creature was the father of the modern horse.

There were the Eocene Eohippus and the Eocene whale. The Eocene Eohippus they say has been coming up, up, up, under the irresistible and unyielding pressure of evolution and is now the horse. What, then, happened to that unyielding and irresistible pressure that it failed to carry along with it the Eocene whale which, instead of coming up, up, up, in comfortable accommodation to the indispensable requirements of evolution, has conducted itself, perhaps because it had flippers, with so much flippant indifference to the pre-opinions, pre-assumptions and prerequisites of those who would have had it reverse its procedure?

They start you off with something very small as the progenitor of the Eocene Eohippus, but the Eocene Eohippus and the Eocene whale had a common ancestor. Why, therefore, was the progenitor of the little squirrel-like creature lagging along the line of evolution while the whale was attaining a length of seventy feet? Everything went forward very nicely with the little Eocene squirrel-like creature, yet we see that something must have stopped altogether while its contemporary, the Eocene whale, was making such monstrous advance. But this is the very apex of paradox, for we see that the little Eocene squirrel-like creature didn't stop at all, but kept going right on, whereas the monstrous advance of its contemporary, the Eocene whale, is seen to be no advance of any kind whatsoever but in truth a sprag in the cogs of evolution.(McCann 181-183)

One of the most important factors contributing to natural selection is environment. It should be obvious that whales and horses evolved in very different environments, so that traits that would have been favored in one lineage may not have been beneficial in the other. But even among each lineage, the different groups within the lineage lived in different environments. Early horse ancestors were forest dwellers. There are many reasons why natural selection may have favored a small size in those populations, such as lower food requirements, ease in getting around through the trees or in the branches, or more places to hide from predators. Modern horses and zebras live on the plains, where large size is by itself a defense from predators, and also allows the animals to run faster.

Modern whales do have very different teeth than their ancestors. In the dolphins and toothed whales, the teeth are actually simpler than most mammal's teeth. They're simple conical teeth. But recall that whales are aquatic predators. They catch slippery fish and eat them whole. They don't need molars to grind up tough plant material. There's also the possibility that the regular sizing and spacing of the teeth allows them to be used as arrays, to help the whales with echolocation.

Then, of course, there are the baleen whales. They have no teeth at all, but it's because they've evolved a complex body part that allows them to filter feed better than plain teeth would have. And yes, scientists have found a transitional form that has both teeth and baleen (more info on baleen whale evolution).

This following paragraph is exactly what common descent means.

Its [a bat's] wings are like our own human hands. That is why they had to start the first horse with five toes. The evolutionist sees modifications of the same structure in the paws of cats and dogs, the hoofs of horse and cattle, the flippers of whales and porpoises, etc., yet the foot of the ape is scarcely so much a foot as a HAND! (McCann 183)

But this? Not so much.

In order, by the slowly acquired accumulation of infinitesimal differences in gigantic periods of time, to develop the primitive generalized fore-limb from which all these diverse forms evolved, the bat before acquiring a wing capable of flight would have had to have countless hosts of ancestors, millions of them, and man should be not a descendant of the ape so much as a cross between a tortoise and a lizard. (McCann 184)

Our ancient, ancient tetrapod ancestor had five toes on each foot, both front and back. Somehow this number became set in development (not that it's impossible to have a different number, but that the change is rather unlikely, particularly an increase). Subsequently, nearly all descendants of that ancient tetrapod ancestor have five toes on each foot. A bat wing is evolved from that ancient limb, as is our arm, a lizard's leg, a dinosaur's claw, or a horse's hoof. All of us subsequent descendants are cousins.

On some issues that McCann's brought up, I haven't been familiar enough with the state of science during his time to know whether science really was lacking in those areas. But on this one, there's no excuse.

But perhaps the bat is an exception among flying things? On the contrary, the same holds good of other flying creatures - birds, pterodactyles (flying lizards), etc. No trace of any of these creatures is found while their wings were in the making. (McCann 184)

Archaeopteryx was discovered in 1861. Surey, McCann should have heard of that, especially if he was doing any research for his book. At the very least, he could have brought it up to discount it, considering how many people have used it as an example of the very thing McCann is asking for.

Ah. A creationist screed just wouldn't be complete without conflating evolution with abiogenesis.

All this positive evidence, all this negative evidence, all this lack of evidence of any kind should demonstrate the folly of the theory that the whole organic world originated in one primitive cell under an accidental chemic urge that has never repeated itself. Moreover, it should show the folly of the theory that the animal and vegetable kingdoms emerged from the same ancestral cell. (McCann 187)

Abiogenesis is not the same thing as evolution. As I already wrote in a previous part of this series, the origin of life is as relevant to the study of evolution as the origin of the atmosphere is to the study of meteorology.

There is, however, a very good reason why we don't see new life springing up any more - advanced life is already here. When life was first getting started on this planet, it had no living competition. There were no hungry critters to gobble up organic molecules floating about, or to gobble up any incipient life. Now, bacteria are everywhere. There's practically no nook or cranny with the conditions where new life could get started that isn't already inhabited by bacteria.

After as much hoopla as there was over punctuated equilibrium when Gould pushed it, I thought it was interesting to read this.

Struck by the amazing lack of uniformity in what is called "the rate of evolution," its proponents must look to De Vries for help. De Vries believed there were periods of rapid change alternating with periods of fixed stability in the history of species. Consequently we find the idea of "periodic advances or waves of evolution." (McCann 188)

Keep in mind though, that De Vries was advocating saltationism, which was a bit different than punctuated equilibrium. When punctuated equilibrium advocates talk of "periods of rapid change alternating with periods of fixed stability", the 'rapid' is only in geologic terms. If you could somehow gather specimens from every generation during the 'rapid change' period, every generation would still look very much like the previous generation, with only slight differences. It's only the accumulation of many of those slight differences over many generations that results in a big change in the population. Saltationists, on the other hand, would predict that there would be a very noticeable difference from one generation to the next.

Saltation, as far as we can tell, doesn't happen. Even if, through the most unlikely of scenarios, a 'hopeful monster' were to be born, it would have no partner to mate with. Punctuated equilibrium, however, does appear to happen. The history of life on this planet seems to be a mix of punctuated equilibrium and gradualism.

I thought it was interesting to read this.

The significance of another admission of this modern Princeton professor [Conklin] is overwhelming. Announcing that one-celled organisms reached their utmost limits of complexity millions of years ago, he crosses the stream of life and reviews the higher animals and plants in all their multiplication of cells, tissues, organs, systems, metameres, and zooids which, he says, p. 20, "enormously increased the possibilities of specialization within each of these larger units of organization, BUT FOR MILLIONS OF YEARS THERE HAS BEEN LITTLE FURTHER PROGRESS IN THIS DIRECTION OF MULTIPLICITY AND COMPLEXITY." (McCann 188-189)

McCann's response shows the typical ego that many people have, considering humans to be separate from the rest of the animal kingdom.

Whence, then, came man with his extraordinary complexity of organization? (McCann 189)

First, I'll refute McCann's response, by simply quoting again something I'd already quoted in a previous part of this series, part of a recent article in the New York Times by primatologist Frans de Waal.

In the field of cognition, the march towards continuity between human and animal has been inexorable... True, humanity never runs out of claims of what sets it apart, but it is a rare uniqueness claim that holds up for over a decade. This is why we don't hear anymore that only humans make tools, imitate, think ahead, have culture, are self-aware, or adopt another's point of view.

If we consider our species without letting ourselves be blinded by the technical advances of the last few millennia, we see a creature of flesh and blood with a brain that, albeit three times larger than a chimpanzee's, doesn't contain any new parts. Even our vaunted prefrontal cortex turns out to be of typical size: recent neuron-counting techniques classify the human brain as a linearly scaled-up monkey brain. No one doubts the superiority of our intellect, but we have no basic wants or needs that are not also present in our close relatives. I interact on a daily basis with monkeys and apes, which just like us strive for power, enjoy sex, want security and affection, kill over territory, and value trust and cooperation. Yes, we use cell phones and fly airplanes, but our psychological make-up remains that of a social primate. Even the posturing and deal-making among the alpha males in Washington is nothing out of the ordinary.

Aside from having a big brain, humans are no more complex than any other mammal. (Actually, I always thought of birds as being more advanced than mammals in many ways, what with their feathers, air sac lung system, superior vision, etc.). In fact, when you get down to genetics, we're not even all that different from single celled eukaryotes or bacteria. All the functions that have to be carried out in our cells have to be carried out in those single celled organisms as well. Sure, we have organs and specialized tissues, but even bacteria can form colonies and have some degree of specialization. I'm not trying to say that we're not more complex than a bacterium. I think we are. I'm just pointing out that the difference isn't as big as some people would think. (On a related note, here's an entry on the evolution of complexity.)

McCann did make a good point that seems to be lost in the current popular notion of evolution, where so many people emphasize genetics in development, ignoring environment.

The composition of the soil determines largely the character of the plant's development, exerting a vast influence upon the variety of the species, the different individuals of which are influenced accordingly. (McCann 190)

In fact, I wrote about this in a previous entry of mine, Genetic Determinism. We're certainly the products of evolution, but we're also the products of our environment.

Proceed to Chapter 15

Website Update - Too Busy

A couple months ago when I started on the God or Gorilla series, I said I was still going to try to come up with another substantive post every week. Well, I'm really busy at work right now, so I'm cutting my lunches short to get things done. So for the next few weeks, I may only have time to do God or Gorilla posts. If anything else gets posted, consider it a bonus.

Friday, May 6, 2011

Book Review - God- or Gorilla?, Chapter 13

This entry is part of a series. For a bit of an introduction and an index of all entries in the series, go here.

God or Gorilla PicThis installment covers Chapter 13, What is a Horse?.

Once again, McCann doesn't seem to understand the whole concept of common descent, and why vertebrates would appear similar to each other.

The most casual observer will not deny the extraordinary similarity. The rearing horse, standing almost upright, so vividly resembles the man in bony structure as to suggest an entirely new line of speculation. There is no monopoly of the ludicrous, no patent rights on the ridiculous! We are not now speaking of a resemblance between man and ape, but between man and horse!

Why did man not evolute from the horse? (McCann 166)

Humans and horses look so similar because we both evolved from a common ancestor, not because we evolved from horses, or horses from us. We're cousins.

If McCann understood this a bit better, he probably wouldn't have been so dismissive in the following paragraph.

At this point the "scientists" kick the great authority on evolution, Professor Huxley, right out of the picture. Perhaps they wouldn't have been so bold if Huxley himself hadn't authorized the act. The Palæotherium comes in with another creature called the Plagiolophus. One of these animals was a direct ancestor of the horse, according to Huxley. Now they admit Huxley was wrong. The critter was only a "collateral relative." (McCann 170)

or here

When they get to Link No. 8 they don't know what to do with Anchitherium and Hypohippus. The first of these fellows has been found only in Europe and the second has given so much trouble, though found in Colorado, that they have had to admit he "is off the direct line of descent." (McCann 170-171)

This is what I was alluding to in the review of the previous chapter. When we find a fossil of an ancient animal that looks similar to an animal living today, we'd like to assume that it's a direct ancestor. We like easy stories and linear relationships. But like I wrote above, evolution creates family trees that look more like bushes. Populations are constantly splitting, creating closely related 'cousin' species. Also keep in mind how spotty the fossil record is, and how much more common it is for species to go extinct than to survive. When you look at it that way, it seems obvious that any fossil you find is most likely to have come from an extinct 'cousin' species, rather than from a direct ancestor of any living animals. Recognizing that is not any admission that evolution is wrong. It's a better understanding of how evolution actually works, and a better understanding of our sampling of the fossil record.

McCann strikes me as the type who would say that the discovery of a 'missing link' just creates two gaps where before there was only one.

Again it is odd that the scientists always find plenty of specimens of the things to be connected but never a single connection. (McCann 175)

Because archaeopteryx isn't obviously intermediate between terrestrial dinosaurs and birds.

Yet again, McCann shows a misunderstanding in assuming evolution to be linear.

According to the evidence itself there was deterioration instead of advance in the evolution of the horse, for the Epihippus which came along "thousands of years" after the Protorohippus is very much smaller than its grandfather when it should be very much larger on its progressive way from a four-pounder to a creature weighing a ton. (McCann 178)

Evolution is not a ladder of progress. It's a drunkard's stagger. There's no reason why the evolution of the horse from prior ancestors would have shown a steady increase in size. Just look at the finch example I used back in Part III of this review. Looking at the evolution of a population of finches on the Galapagos, average beak size was observed to increase in some years, and decrease in others, depending on the selective pressures operating on the population at the time. There's no reason to assume that horse's ancestors would have increased in size over their entire course of evolution from something like hyracotherium.

Proceed to Chapter 14

A Visitor at Dusk

The other day, just after I had gotten home and gotten out of the car, I heard a rustling in the bushes in front of our house. My first thought was that it was the cats, but I realized that our cats aren't clumsy enough to make that much noise. So, I took a step back, and waited to see what would come out.

Armadillo in my Driveway

It's a bit hard to tell from the grainy photo from my cell phone, but that's an armadillo. I've seen a few dozen armadillos, but what makes that one unique, after my having lived in Texas for nearly ten years, is that it's alive. Honestly, every single armadillo I've seen before this one (not counting zoos), has been roadkill. It probably has something to do with me living and working inside the city limits, but I've seen living bobcats, coyotes, skunks, possums, rabbits, beavers, foxes, raccoons, deer, bats, and plenty of other animals, but never a live armadillo.

I followed this one around the neighborhood for about 10 or 15 minutes before it finally went through a neighbor's backyard into a strip of trees. My daughter just missed seeing it, but at least heard it rustling in the woods.

Website Update - Top 10 Page List for April 2011

Top 10 ListWell, it's the start of a new month, so it's time to browse through the server logs again to come up with the list of the top most popular pages on this site from last month. There were no surprises - everything on the list had made it before, though there was a bit of shuffling around. The MBT Shoes entry still maintained its lead over the Autogyro History & Theory page.

My surge in traffic has dwindled a bit. I still had significantly more traffic in April than before the surge began, but less than in the previous 3 months.

Anyway, here's the top 10 list for April:

  1. Blog - A Skeptical Look at MBT Shoes
  2. Autogyro History & Theory
  3. Blog - Casio EX-F1 - First Impression of the High Speed Video
  4. Blog - Response to Anti-Liberal Article by Gary Hubbell
  5. Blog - Origin of Arabic Numerals - Was It Really for Counting Angles?
  6. Blog - Book Review - Voyage of the Beagle
  7. Blog - Running AutoCAD R14 in XP Pro 64
  8. Blog - Ray Comfort - Still Ignorant on Evolution
  9. Blog - The Texas Republican Platform, or Why I'm Not a Republican
  10. Blog - My Favorite Airplanes

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