Part 5: The Gulf Between Reptiles and Birds
Alan Feuerbacher
What about the supposed transition from reptiles to birds? At first glance the argument against this transition appears quite simple, as the Creation book explains. On page 75, under the subheading "The Gulf Between Reptile and Bird," paragraph 11 says:
Reptiles are cold-blooded animals, meaning that their internal temperature will either increase or decrease depending upon the outside temperature. Birds, on the other hand, are warm-blooded; their bodies maintain a relatively constant internal temperature regardless of the temperature outside. To solve the puzzle of how warm-blooded birds came from cold-blooded reptiles, some evolutionists now say that some of the dinosaurs (which were reptiles) were warm-blooded. But the general view is still as Robert Jastrow observes: "Dinosaurs, like all reptiles were cold-blooded animals."
The quote from Jastrow was from 1979; since then the general view has changed. The idea that dinosaurs were warm-blooded came from many considerations other than simply trying to show bird ancestry. A great deal information has appeared within the last twenty five years about the warm-bloodedness of dinosaurs, which is only lately becoming widely accepted among scientists, and which may not have been so readily available when Creation was published in 1985. One of the best and most comprehensive books on this subject is The Dinosaur Heresies,73 published in 1986. The author, Robert T. Bakker, has been involved in the search for clues about the dinosaurs' lives for many years. A reviewer's comment from the back cover well describes the book:
Reading The Dinosaur Heresies was sheer joy. Bakker explodes old myths and presents us, instead, with a dynamic panorama which seems so much more true to life. This points the way to a fuller understanding of the long reign of the dinosaurs. Soon most of the heresies will be heresies no longer.
Bakker says concerning the key scientific papers that have been published recently on the topic of warm-blooded dinosaurs:74
The two milestone volumes are: 1) the AAAS Select Symposium 28, Westview Press, 1980...; and 2) the Los Angeles County Museum of Natural History Special Colloquium Dinosaurs Past and Present, LACM Press (1986). Nearly every important paper about warm-bloodedness, pro and con, are cited in these two volumes. The difference in tone between the two is remarkable. The 1980 AAAS book was unapologetically skeptical -- even the title Cold Look at the Warm-Blooded Dinosaurs suggested that belief in warm-blooded Dinosauria was rash and beyond the boundaries of level-headed science. But the LACM volume contains articles by those who reconstruct dinosaurs and their world, and, with few exceptions the artists, anatomists, and paleontologists accord the dinosaurs a much, much higher level of locomotor energetics than was widely believed six years ago. Sylvia Czerkas, the editor and organizer of the LACM colloquium, said to me after the conference, "You must be feeling pretty good, seeing your ideas vindicated more and more." Maybe so. At least the general attitude is shifting away from the view that dinosaurs must be assumed to be cold-blooded in all points and any contrary evidence dismissed with a "harrumph."
Typical of the information coming out of recent research on dinosaurs is an article in Scientific American, April, 1991, "How Dinosaurs Ran," which concluded that dinosaurs were generally about as athletic as modern day mammals that are built according to similar body plans. Brontosaurus, up to about 50 tons, was about as athletic as an elephant. Triceratops, about the size of an elephant but with a relatively much stronger bone structure, must have been about as athletic as a rhinoceros. This strongly points to warm-bloodedness.
What does the fossil record show about animals that might have been warm-blooded? In the early Triassic Period, a group of mammal-like reptiles called therapsids (synapsids) appeared in the fossil record. Somewhat later there appeared a group of animals called thecodonts, which are said to have been ancestral to the dinosaurs. About the same time as thecodonts, the first mammal-like animals, turtles, crocodilians and frogs appeared.75 There are a great number of questions with regard to this early life, one of which is whether it was warm-blooded. Based on many considerations, Robert Bakker and others have argued that both therapsids and the dinosaurs were warm-blooded. Bakker also calls the therapsids protomammals, and says of them:76
They definitely included the immediate ancestors of genuine mammals -- and the advanced protomammals showed many signs of mammal-style adaptations in their body and skull. Most paleontologists therefore are willing to believe these later protomammals had already developed some degree of warm-bloodedness. Now, if they were warm-blooded, it is very strange indeed that they subsequently lost their dominant position to the supposedly cold-blooded dinosaurs.
The book Extinction says:77
It is puzzling that the therapsid mammal-like reptiles had a considerable head start on the dinosaurs, and yet the dinosaurs expanded to dominate terrestrial habitats of the Mesozoic Era. Robert Bakker of The University of Colorado Natural History Museum has argued persuasively that this fact attests to the inherent superiority of the dinosaurs -- and, in fact, of the thecodonts. These dinosaur ancestors, even before the dinosaurs themselves, seem to have begun to displace the therapsids. Even the early mammals were left behind, failing to undergo their great adaptive radiation until nearly 200 million years later, after the dinosaurs' demise. Bakker has viewed the dinosaurs' ecological dominance as offering strong testimony that they were endothermic ("warm-blooded"). Reptiles, which depend on external sources of heat energy, are unable to sustain high levels of activity for long intervals of time, whereas mammals, with their continuously high metabolism, can remain active for hours. The question is, if dinosaurs were saddled with a reptilian physiology, how could they have maintained ecological superiority over mammals? Even stronger evidence that dinosaurs were to a considerable degree endothermic comes from predator/prey ratios. In a community of mammals, which are of course endothermic, there is a relatively small number of predators compared to the number of herbivores. The reason for this is that the predators, being endothermic, need a great deal of fuel to stoke their metabolic furnaces. An example is the small number of lions, cheetahs, hyenas, and wild dogs on an African savannah compared to the huge herds of wildebeests, zebras, gazelles, and other herbivores that serve as prey. In contrast, carnivorous reptiles tend to be relatively abundant within their communities. Being ectothermic, they require little food. Bakker has shown that in dinosaur communities, predator/prey ratios were consistently very low, resembling those of mammals -- strong evidence that dinosaurs were endothermic.
Bakker has given the following additional evidence that dinosaurs were warm-blooded:
Histological studies show dinosaur bone microtexture is much closer to mammal and bird bone than to ancient reptile bone. This implies fast growth rates, which requires warm-bloodedness. This type of bone texture is seen in all size dinosaurs, from 5 pounds to 70 tons adult weight.78
Many dinosaurs had hollow vertebrae, like most birds do. In birds the hollows are intimately connected to the lungs and a system of air sacs, which are required to support their generally high level of activity. No ancient reptile had hollow bones and no living reptile has either hollow bones or air sacs.79
Dinosaurs apparently had gizzards, as do birds and most reptiles. This would have allowed them to eat whatever quantity of food necessary to sustain internal body temperature, as the gizzard system of digestion is more efficient than that of any mammalian system.80
More and more paleontologists are coming around to Bakker's point of view that dinosaurs were warm-blooded, but since the scientific community suffers from a great deal of inertia, as do all human institutions, the shift is slow. Nor has this information filtered significantly into popular consciousness. This change in overall viewpoint appears to be one of the large "paradigm shifts" that science undergoes from time to time, like the revolution in the earth sciences of the 1960s to 1970s. Bakker sums up his view that dinosaur classifications should be changed thus:81
Most taxonomists... have viewed such new terminology as dangerously destabilizing to the traditional and well-known scheme that has been with us since the time of Baron Cuvier. I cannot see any benefit to be gained by refusing to remove the dinosaurs (and the therapsids) from the confines of the Reptilia. Classification is a type of scientific definition, and definitions should help express our perceptions of nature, not hinder them. As long as textbooks and museum labels unreflectively repeat the message "Dinosaurs are reptiles," it will be difficult to establish an intelligent debate about the true nature of the dinosaurs' adaptations. Some of the orthodox paleontologists act as though the dinosaurs must be assumed cold-blooded until their warm-bloodedness is proved beyond any reasonable doubt. That is at least highly unscientific. And it certainly represents "argument by definition" -- dinosaurs are reptiles, reptiles are cold-blooded, therefore dinosaurs were cold-blooded.
A truly scientific skeptic would start by assuming neither cold-bloodedness nor warm-bloodedness, and then reevaluate the evidence without prior terminological bias. So long as the Dinosauria remain stuck in the Class Reptilia, this type of analysis is nearly impossible. Let dinosaurs be dinosaurs. Let the Dinosauria stand proudly alone, a Class by itself.
Did dinosaurs care for their young? Apparently they did. Extinction describes the fossil evidence.82
Dinosaur fossils offer evidence of relatively advanced reproductive behavior as well. In Cretaceous rocks of Mongolia and the western United States, eggs can be found arrayed in rings, as if they were very precisely buried. The eggs were tapered toward one end, this end having been thrust into the ground by the mother. Even more revealing is the discovery... of nests of baby dinosaurs in rocks of late Cretaceous age in Montana. The first to be found was a cluster of skeletons, each about a meter... long, surrounded by broken eggshells in a depression on top of an ancient hill. The nests demonstrate that dinosaurs cared for their young after they hatched.
Were dinosaurs like birds? Creation puts dinosaurs in the reptile class, and then proceeds to show how different are modern birds from modern reptiles. As the above quotation says, this is "argument by definition." What do the fossils show?
One late Triassic dinosaur was discovered in New Mexico by Ned Colbert of the American Museum. A whole quarry full of complete and partial skeletons was found:83
Colbert's splendid skeletons seem to belong to the same genus Cope had named from fragments in 1880: Coelophysis, roughly translated as "hollow-boned beast." Hollow it indeed was -- all of the major limb bones and vertebrae were constructed like those of birds, with an outer shell of dense bone rind surrounding an empty core. So perfect are Colbert's skeletons that no guesswork is required to reconstruct these bodies. Coelophysis was small compared to its Jurassic nephews Allosaurus and Ceratosaurus; the fully adult length was only six feet, half of which was tail. Compared to those Jurassic predators, Coelophysis was long and slender in the torso and very long in the neck -- the neck, body, and tail all seem to flow into one another to create an unusually smooth profile. Although it appeared early in dinosaur history, Coelophysis was already a birdlike biped with wide upper hip bones and deep lower hip bones, the whole design providing for ample thigh muscles and quick thrusts of the hind leg. The vertebrae in the neck were angled, producing a natural S-shaped curve, so the head was carried high above the shoulder as a bird's would be.
An entire group of flying creatures (not classified as dinosaurs) called pterosaurs and pterodactyls existed. They ranged from robin size to airplane size -- up to forty foot wing spans. They were as exquisitely built for flight as any modern bird:84
Pterodactyls... were equipped to fine-tune the shape and camber of their wings... the deep keel of the breastbone showed that the "white meat" muscles were as large relative to the body's size as are those of many flying birds today... In fact... pterodactyls were more fully committed to an active aerial way of life than any modern bird or bat, with the possible exception of swifts or hummingbirds... The pterodactyl's entire torso was highly compact from front to rear and the whole was reinforced by two rigid bony girders... these shoulder and hip braces made the pterodactyl's torso a light but incredibly strong boxwork of bony struts, exceeding in strength the body of the most modern birds...
Bird skeletons delighted medieval anatomists because of their lightness and economy. The bones of most flying birds are of a tubular-strut design. All the major limbs are cast in a thin-walled, hollow construction. Just so were the pterodactyl's bones designed. Even the apparently massive upper arm bone (humerus) of the gigantic Texas pterodactyl had only an outer shell of very hard bone a few millimeters thick. And just as avian bones achieve their greatest lightness by being filled not by marrow but by a core of air sacs connected to the lungs, likewise the pterodactyl's bones are constructed to contain air-sac liners. Though lung tissue itself is never preserved in fossils, the presence of air sacs can be detected from the characteristic pores in the bony walls which provided entrance for the air canals.
So hollow bones are not unique to birds. Even some very large dinosaurs had hollow bones:85
Many dinosaurs had hollow cavities in their vertebrae. A single bone of a Brontosaurus's spine is so full of holes and indentations that the actual bony tissue is reduced to thin partitions, often a few millimeters thick, folded and convoluted many times to produce the major structural contours. Allosaurus and other meat-eaters also had such hollowed-out vertebrae, though to a lesser extent than in the brontosaurs. What filled the vertebral holes and hollows is not difficult to see because very similar hollow backbones can be found in today's bird's. In them, the hollows are filled by air sacs connected by tubes to the lungs.
At least some of these pterodactyls even had a hair-like covering:86
... most paleontologists have assumed, since pterodactyls were classified as "reptiles," that they had a naked, scaly skin. Such images certainly dominated the restorations of pterodactyls until 1970, when a startling report arrived from a Russian paleontologist: Hairy pterodactyls had been found in Russia. Professor Sharov had been engaged in separating the slabs of Jurassic lake beds which preserved delicate leaves and insects. In one split slab lay a pterodactyl -- not unusual in itself. But highly unusual was the near-perfect preservation of the pterodactyl's body covering -- a dense coat of long, hairlike scales... Other specimens have confirmed Sharov's discovery. Flying dragons as a group seem to have been insulated. Were they alive today, it is very much to be doubted whether biologists would place them in Class Reptilia.
The flying "reptiles" are actually one of the best evidences against evolution, even though evolutionists explain them as products of greatly speeded up evolution:87
Flying dragons seem to burst into the world like Athena from the mind of Zeus, fully formed. Even the earliest skeletons of pterodactyls already display fully developed wings and the specialized torso and hips so characteristic of the entire order. Cases like this in paleontology -- and there are many more -- persuade many scholars that evolution doesn't work slowly and continuously at one even pace. Instead, there appear to be times when evolution speeds up and suddenly produces totally new adaptive configurations. Pterodactyls must have emerged in one of these creative spurts of the evolutionary process.
Keeping in mind everything said above, reflect on Creation's statement on page 77. Note that Creation speaks of reptile bones rather than dinosaur bones:
Consider further the design of the bird for flight. The bird's bones are thin and hollow, unlike the reptile's solid ones. Yet strength is required for flight, so inside the bird's bones there are struts...
Next note what a recent article had to say about experiments to determine the ability of birds to cool off due to strenuous exercise:88
... many fully feathered modern birds also dissipate heat by high rates of cutaneous evaporation across feathered skin... experimentally heat-stressed sand grouse... radiate heat (via evaporation) from their feathered skin at about 80% the rate of heat loss from naked skin... Similarly, during sustained flight in white-necked ravens... evaporative cutaneous heat loss accounts for about 8 times the magnitude of heat loss dissipated from respiratory surfaces.
The author of Creation is totally unaware of this aspect of bird physiology, since he continues:
This design of the bones serves another purpose: It helps to explain another exclusive marvel of birds -- their respiratory system.
Muscular wings beating for hours or even days in flight generate much heat, yet, without sweat glands for cooling, the bird copes with the problem -- it has an air-cooled engine... A system of air sacs reach into almost every important part of the body, even into the hollow bones, and body heat is relieved by this internal circulation of air.
It is a continual source of amazement as to where Creation's author gets his information.
In light of the above evidence from the fossil record it should be clear that Creation's statements that dinosaurs are reptiles and therefore birds must be very different from dinosaurs, birds and dinosaurs have no common characteristics, and similar things based on the difference between present day reptiles and birds, are wrong.
While the evidence that birds evolved from dinosaurs is relatively sparse, there is far more evidence than presented above that birds were similar to certain dinosaurs, and that bears on whether birds evolved from reptiles. The most famous and controversial single example is an early form of bird called Archaeopteryx, which had teeth and a long bony tail, and is the most ancient bird yet found.88a We now present detailed information on Archaeopteryx and show the cavalier manner in which Creation dismisses all this evidence. Here is a summary of current scientific opinion of Archaeopteryx:89
The first skeleton of this creature was found in 1861. The 140-million-year-old (Late Jurassic) lithographic limestone in which it was found also contained the skeletons of small carnivorous dinosaurs known as Compsognathus longipes. What made Archaeopteryx so strikingly different from these dinosaurs was the unmistakable impressions of feathers, the hallmark of birds. It displayed a few other features otherwise found only in birds, but most of its anatomy was reptilian and very similar to that of the small running dinosaurs with which it was found... In fact, another skeleton of Archaeopteryx collected in 1855 was not recognised as such until 1970 because, lacking clear impressions of feathers, it had been assumed to be another skeleton of Compsognathus.
The five skeletons of Archaeopteryx now known have been the subject of many detailed anatomical studies. The conclusions are always the same; this is an animal that belongs in the structural and temporal gap between reptiles and birds. It would be difficult to imagine a more perfect link. If there has been any significant debate among palaeontologists about the evolutionary significance of Archaeopteryx, it is not about its intermediate position between birds and reptiles but rather about the particular group of reptiles to which it is most closely related.
The remarkable resemblance between the skeletons of Archaeopteryx and Compsognathus can be seen in a drawing in one of the books from the Scientific American Library.90
Fossil birds from times later than Archaeopteryx have been discovered. Some of them also had teeth, but were much more like modern birds in other respects, so there is no controversy about whether they could be called birds. About 1885 professor Marsh of Yale University discovered the fossils of two toothed birds in Late Cretaceous deposits in Kansas, and called them Odontornithes ("toothed birds"):91
Marsh's fossils had undeniably been birds -- the smaller ones, Ichthyornis ("fish-bird"), possessed powerful wings constructed nearly exactly according to the plan found in living avian species. Marsh's bigger bird, Hesperornis ("western bird"), had clearly been flightless -- only the remnants of wing bones remained -- but its vertebral column and hind legs were of typically avian architecture. Hesperornis had clearly swum like a loon... But both Ichthyornis and Hesperornis had had teeth set in their jaws -- sharply pointed, curved teeth with big roots, just like those of crocodiles. And Marsh detected other more subtle remnants of reptilian ancestry: the upper wing bone (humerus) of Ichthyornis featured a wide crest for supporting the flight muscles, and this bony crest more resembled the one along a dinosaur's arm bone than the structure found in any modern birds. Ichthyornis also had simple dinosaur-style joints between its neck vertebrae -- the vertebral bones met at flat bony surfaces, unlike the strongly involuted, saddle-shaped joints of all modern birds...
In 1861, the lithographic limestones in Bavarian quarries yielded a fossilized bird from the Jurassic Period, Archaeopteryx (ancient wing). The Bavarian discovery consisted of a nearly complete skeleton of a dinosaurlike animal, strongly resembling Ornitholestes,91a with long hind legs and a very long tail. But there, on the carefully chipped-out limestone slabs, impressed into the fine limy mud before it had hardened, were also the unmistakable impressions of long flight feathers attached to the forearm and wrist and big tail feathers trailing behind... At first, the details of Archaeopteryx's skull and jaws remained obscure, because the head was the worst preserved part of the skeleton... in 1877, the Bavarian quarries yielded a second Archaeopteryx skeleton, and detailed analysis uncovered the startling pro-Darwinian evidence: Archaeopteryx too had had teeth, and everywhere the structure of its joints and muscle processes had been much less birdlike and far more primitive than those of the Odontornithes of the Cretaceous... truly modern birds without teeth made their debut at the very end of the Cretaceous and the beginning of the next epoch, the Paleocene.
Several other animals have been found that have been called links in the chain between reptiles and birds:92
There is much more that is fascinating about the early evolutionary record of birds in terms of our present interest in 'links'... for example, the Middle Cretaceous toothed birds (such as Ichthyornis dispar) represent a structural link between the Jurassic Archaeopteryx and the modern orders of birds, most of which made their first appearance in the Early Tertiary. These Cretaceous toothed birds display more avian features than did Archaeopteryx including a shortened tail, a synsacrum, a tarsometatarsus and uncinate processes on the ribs (see Table 6.1 for a brief definition of terms).
Recently, a fascinating fossil bird that is intermediate in time between Archaeopteryx and the Middle and late Cretaceous palaeognathous toothed birds has been described. Ambiortus dementjevi, an Early Cretaceous bird from Mongolia, is known from associated parts of a wing, shoulder girdle and vertebrae. Its pectoral apparatus shows features that are more like those of modern birds than the comparable conditions in the Late Jurassic Archaeopteryx while in other respects it closely resembles primitive palaeognathous birds recently discovered in the Paleocene and Eocene of North America and England...
There is even a fossil record of feathers that demonstrates a structural gradient between simple reptilian scales and the complex feathers of Archaeopteryx... This fossil scale-to-feather transition is supported by studies of the embryology of the scales of living reptiles and the feathers of living birds. Feathers are a very specialised type of reptilian scale.
The meat-eating dinosaurs such as Allosaur, Coelophysis, Compsognathus, and Ornitholestes were similar to birds in ways originally elucidated by Thomas Huxley in the 19th century:93
Huxley's case was impressive in documentation, persuasive in argument: (1) Only in dinosaurs did he find the distinctive bird type of ankle joint, where movement had been concentrated into a single hinge running between the two rows of ankle bones. (2) Only in dinosaurs had he found the great expansion of the upper hip bone (the ilium) so characteristic of all birds. (3) Only in some dinosaurs had the hind foot been arranged in a birdlike fashion where the inner toe turned backward and the three main toes pointed forward to produce the unmistakable footprint of birds. In fact, some dinosaur tracks were so birdlike that they had been mistaken for bird tracks when discovered in 1830. (4) Only advanced dinosaurs displayed the compact bipedal body fundamental to avian anatomy -- the very short torso, massively braced hips, long and highly mobile neck, and long hind legs. (5) Only in dinosaurs and pterodactyls had Huxley noted holes in the vertebral bones for the air sacs which connected to avian-style lungs, and the pterodactyls had been far less birdlike than advanced dinosaurs in most other regards. (6) Only in some dinosaurs had the pubic bone been turned backward exactly as in birds.
Another dinosaur called Deinonychus existed at the same time as Archaeopteryx, and except for size, the skeletons of the two were much alike:94
Some large dinosaurs obviously were most unbirdlike, Diplodocus or Triceratops, for example. But the bipedal predators were very avian in structure. And the small, advanced predators like Deinonychus were so close to Archaeopteryx in nearly every detail that Archaeopteryx might be called a flying Deinonychus, and Deinonychus, a flightless Archaeopteryx. There simply was no great anatomical gulf separating birds from dinosaurs.
Here are more details on the two animals:95
In 1964, John Ostrom at Yale discovered the very advanced predatory dinosaur Deinonychus, a long-armed Early Cretaceous carnivore with a cruel-looking killing claw on its hind foot... Biomechanical analysis applied to Deinonychus's bodily configuration yielded evidence for exceptionally high levels of locomotive activity: both running speed and maneuverability. Quite clearly, Deinonychus had had a great deal of birdness built into its limbs, a birdness that would have expressed itself in life by a daily metabolic regime more fitting for a ground bird such as a cassowary than for the orthodox view of any cold-blooded dinosaur... in a Dutch museum [Ostrom] found a set of bony fingers on a limestone slab out of those famous Bavarian quarries... He recognized the bony hands with their three long, clawed fingers as belonging to Archaeopteryx. But he also recognized in that hand a miniature version of Deinonychus's. Archaeopteryx had been pigeon-sized, its hand four inches long; Deinonychus had been as heavy as an average man and could stretch its hand a full nine inches. Yet the small bird hand and the dinosaur hand were virtually identical in shape. Each finger and wrist bone had been molded to the same peculiar biomechanical pattern, an adaptive plan totally unknown anywhere in the animal kingdom outside the Dinosauria... Between Archaeopteryx and Deinonychus the long bony fingers were not the only things identical. So was nearly every detail of their shoulder, hip, thigh, and ankle... And in its wrist Deinonychus's similarities to birds were nothing short of astounding...
So according to the fossil record, there are similarities between the dinosaur family and the bird family, and between particular dinosaurs and particular ancient birds.
Why is Archaeopteryx such an important fossil? John H. Ostrom of Yale's Peabody Museum explains:96
Possibly no other zoological specimens, fossil or Recent, are considered so important as are those of Archaeopteryx lithographica... Certainly few other specimens have generated such widespread interest or provoked as much speculation and controversy. The reasons are several: these specimens are the oldest... known fossil bird remains; they are extremely rare, only five specimens... are known at present; several of these preserve remarkably detailed impressions of feathers and an extraordinary mixture of reptilian and avian characters; and most important of all, because of the last fact, out of all presently known fossil and living organisms, these specimens are widely recognized as constituting the best example of an organism perfectly intermediate between two higher taxonomic categories -- representing an ideal transitional stage between ancestral and descendant stocks. Archaeopteryx may well be the most impressive fossil evidence of the fact of organic evolution.
A Scientific American article said:97
With its reptilian body and tail yet undeniably birdlike wings and feathers, Archaeopteryx provides paleontologists with their most conclusive evidence for the evolution of birds from reptiles.
Those arguing against the theory of evolution understand these points very well; that is why virtually all creationist publications contain strong statements that Archaeopteryx was a bird and was not a transitional form. There exists much information about Archaeopteryx's body structure relative to modern birds and to dinosaurs. The following material summarizes the differences and similarities.
These are the ways in which Archaeopteryx was similar to most modern birds:
It had feathers and a wing shape virtually identical to those of modern birds.98
It could fly, but probably not very well.99, 100, 101
It had hollow bones.102, 103
It had a wishbone.104, 105
It had feet and claws similar to those of modern birds.106
Its quadrate bone (which attaches the neck to the head), was similar to modern birds.107, 108
These are the ways in which Archaeopteryx was different from all modern birds:
It had teeth and a tail.109
It had no sternum (breastbone).110, 111
It had abdominal ribs.112, 113, 114
It had no air sac openings in its bones.115, 116
Its vertebrae lack the saddle-shaped articulations that are characteristic of modern birds.117
It appears to have had no attachment points in its skeleton for its feathers (quill nodes), but instead they were attached to the skin.118
The structure of its upper chest and shoulder bones was different from modern birds.119
These are the ways in which Archaeopteryx was different from most modern birds:
It had poorly developed muscle attachment points for the wings.120
Its pelvis had both avian and reptilian characteristics.121, 122, 123
Its feet were similar to those of modern birds, although noticeably different. There seems to be some controversy about exactly what the feet were designed to do -- were they better suited for perching on tree branches or for running on the ground?124, 125
It had three clawed fingers on its wings, which were quite similar to those of certain small dinosaurs.126, 127, 128
Parts of the upper arm structure were different from modern birds'.129, 130
Based on the above considerations, Archaeopteryx was probably not a good flier.131
This picture of Archaeopteryx as a poor flyer seems to be a bone of contention with creationists. There doesn't seem to be any real problem here; many birds today don't fly well or at all. The South American hoatzin has some characteristics that seem much like those of Archaeopteryx, especially with regard to flying ability. Refer to the characteristics of the hoatzin chick, as described by Robert Bakker in footnote 125 and footnote 128 of this essay, for more information on the hoatzin. The July 8, 1986 Awake! also described the hoatzin's flying ability:
[The] crop is so large that there is little room in the chest for strong muscles. The result? Hoatzin is a poor flyer. Admittedly, when you hear the loud, whirring sound of this bird in flight, you imagine him to be the picture of grace. But not so. Oh, he tries hard enough -- flailing his wings strenuously, going all out but hardly moving. Actually, he looks more like a helicopter taking off than a sleek airplane. During a short flight of about a hundred meters, he screeches protestingly with every tiring beat of his wings, eager to touch down as soon as possible.
After describing why the shape of Archaeopteryx's wing feathers show that it could fly, The Dinosaur Heresies said:132
Therefore Archaeopteryx very probably did indulge in powered flight, even though it must have been a noisy, slow, and inelegant performer in the air.
This is exactly Awake!'s description of the hoatzin's flight.
These are the characteristics in which Archaeopteryx was similar to most dinosaurs:
It had teeth and a tail.
It had no sternum.
It had gastral ribs.
It had no air sac openings in its bones.
These are the characteristics in which Archaeopteryx was similar to a few dinosaurs:
It had a wishbone.133
It had hollow bones.134
It had three clawed fingers on its wings.135
Its pelvis had both avian and reptilian characteristics.
Overall, the skeleton of Archaeopteryx was so similar to that of other small dinosaurs that one authority stated:
It has been stated (Colbert, 1969) that if it were not for the impressions of feathers, it is unlikely that the London and Berlin specimens of Archaeopteryx would have been identified as "bird" remains, but instead would have been labeled reptilian. (Recall the early debate about feathered reptile versus reptilian bird.) I would go even further than that. Were it not for those remarkable feather imprints, today both specimens would be identified unquestionably as coelurosaurian theropods.136
... the question must still be asked: How would those [Archaeopteryx] fossil remains have been identified -- indeed, how would they now be classified, if no feather imprints had been preserved in any of those specimens? The skeletal anatomy of Archaeopteryx, as I have demonstrated, is almost entirely coelurosaurian... and includes only one exclusively avian character -- the furcula. In fact, it is only because of the distinct feather impressions preserved in two of the specimens of Archaeopteryx that we now have any knowledge at all about Jurassic birds or about the origin of birds. In the absence of those feather impressions, I do not believe that any of the specimens of Archaeopteryx would ever have been recognized as avian, or even as remotely related to birds.137
The above was published in 1976. By that time several previously misidentified Archaeopteryx fossils had already come to light:138
The fifth specimen, too, was misidentified at first... It was found... in 1951... it was initially taken to be a small reptile similar the chicken-size Compsognathus. Not until 1971 was it recognized as an Archaeopteryx... when [a worker] illuminated the fossil from the side to reveal the faint impressions of wing and tail plumage.
Another specimen was identified in 1987:139
The sixth and most recently discovered specimen of Archaeopteryx came to the world's attention in 1987, when Gunter Viohl, the curator of the Jura Museum... spotted the prehistoric bird in a collection of fossils belonging to... [the] former mayor of Solnhofen. No imprints of feathers were apparent, and most of the skull had been lost. Because of its long, strong hind legs and long tail, the fossil was initially mistaken for that of a Compsognathus... This Archaeopteryx was fully the size of a modern chicken.
The resemblance to certain small dinosaurs was the basis for a charge the Archaeopteryx fossil in the British Museum of Natural History was a fake. In 1985 British astronomers Fred Hoyle and Chandra Wickramasinghe claimed that140
a forger had created the specimen by first applying a thin layer of binding material mixed with pulverized rock to the fossilized skeleton of Compsognathus -- a type of small dinosaur called a theropod -- and then making impressions of feathers in it... Ironically, the features that Hoyle saw as proof of the fossil's inauthenticity -- its mixture of Compsognathus-like bones and modern feathers -- are some of the most important clues that paleontologists have for understanding how birds and bird flight evolved. Its combination of anatomical characteristics from two distinct classes of animals make Archaeopteryx, the oldest-known bird, a textbook example of a transitional form between reptiles and modern birds.
Not all references agree with John Ostrom's conclusion that Archaeopteryx would have been classified as a small theropod.141
In the above pages we have contested this last viewpoint and presented evidence that the sister group (of Ostrom) or ancestral relationship between coelurosaurs and birds was based only on general similarity and not on synapomorphies.
Ostrom has stated that the skeleton of Archaeopteryx is essentially identical with that of some small theropod dinosaurs... We think that many of these "coelurosaurian" features are incorrectly identified.
The very fact that a number of competent paleontologists disagree on minor details of Archaeopteryx's anatomy should convince any reader that there are significant similarities between it and the small dinosaurs mentioned above. It is not justified to conclude that Archaeopteryx was "just another bird, and that's all that needs to be said." All a reader has to do to convince himself of what has been said up to this point is look at photographs and drawings of the fossils in question. Good comparative diagrams of Archaeopteryx, the small dinosaurs to which its skeleton was similar, and modern birds are found in Scientific American,142 the Biological Journal of the Linnean Society,143 and National Geographic Magazine.144
Francis Hitching, who we have met before, disputes the hypothesis that Archaeopteryx represents a transitional form.145 But he ignores evidence such as presented above, and misstates other evidence, with respect to its being an intermediate:
... is the case for Archaeopteryx quite so unambiguous as these claims make out? Apparently not. Every one of its supposed reptilian features can be found in various species of undoubted birds.
1 It had a long bony tail, like a reptile's on which feathers grew.
While it is generally true that reptiles have tails, and birds appear not to, the detailed position is more complex. In embryo, some living birds have more tail vertebrae than Archaeopteryx does, which later fuse to become an upstanding bone called the pygostyle. The bone and feather arrangement on a present-day swan shows striking similarities to Archaeopteryx. According to one authority, there is no difference in principle between the ancient and modern forms: 'the difference lies only in the fact that the caudal vertebrae are greatly prolonged. But this does not make a reptile'.
Hitching provides no source references for this discussion, an inexcusable omission. In any case the above argument is silly. Although a swan has many tail vertebrae, have you ever heard of a swan with a tail as long as its body, as Archaeopteryx had? As for there being no difference in principle between a long and a short tail, monkeys have long tails, but humans have tails where all the bones fuse together during fetal development so that the "tail" is entirely internal. Does this argue that monkeys and humans are no different "in principle"? The same argument could be used to "prove" all vertebrates are the same "in principle" because they have backbones.
2 It had claws on its feet and on its feathered forelimbs.
But so do some modern birds, such as the hoatzin in South America and the touraco in Africa. The ostrich of today, which also has three claws on its wings, has been suggested by some experts to have more supposed reptilian features than Archaeopteryx -- but nobody, of course, considers the ostrich a transitional form.
Claws on its feet? This is hardly a controversial point. The hoatzin has wing claws only during the hatchling stage, as already mentioned in the above discussions. The adult wing is the same as other bird wings -- the claws have fused into a solid bony structure. This is quite different from Archaeopteryx.
3 It had bony jaws lined with teeth.
Modern birds do not have teeth. But many ancient birds did, particularly those in the Mesozoic, and there is no suggestion that these are intermediates. It is just as convincing to argue that Archaeopteryx was an early bird with teeth.
The fact that Mesozoic birds had teeth and modern birds do not is precisely what evolutionists argue is evidence of the gradual change from exclusively reptilian to exclusively birdlike features. Archaeopteryx, which is the earliest bird that has been clearly identified as such, has teeth as well as other anatomical features, that except for the feathers, make it much more like certain dinosaurs than like chickens. The later Mesozoic birds, such as the Hesperornis and Ichthyornis referred to earlier, are anatomically much closer to modern birds. This succession in time is what evolutionists interpret as a succession of evolutionary forms. Hitching totally ignores this point.
4 It had a shallow breastbone that would have given it a feeble wing beat and poor flight.
Modern woodcreepers such as the hoatzin have similarly shallow breastbones, and this does not disqualify them from being classified as birds. And there are, of course, many species of bird, now and in the past, which are incapable of flight.
Where does Hitching get his information? As shown above, the fossil record indicates, not a shallow breastbone, but no breastbone in Archaeopteryx. There may have been a cartilaginous breastbone, but there is no fossil evidence for this. There are no birds besides Archaeopteryx, either modern or in the fossil record, that entirely lack a breastbone. Hitching's argument strikes out again.
5 Its bones were solid, like a reptiles's, not thin or hollow, like a bird's.
Another idea that has been drastically revised. The long bones of Archaeopteryx (wings, legs) are known now to have been both thin and hollow. It is still debated whether they were 'pneumatized' like a bird's, i.e. containing an air sac.
At last, one entirely correct statement.
6 It predates the general arrival of birds by sixty million years.
Until 1977, Archaeopteryx was uniquely early in the fossil record. But in that year, archaeologists from Brigham Young University discovered, in western Colorado, a fossil of an unequivocal bird, in rocks of the same period as Archaeopteryx. Professor John H. Ostrom of Yale University, who positively identified the specimen, commented: 'It is obvious we must now look for the ancestors of flying birds in a period of time much earlier than that in which Archaeopteryx lived.'
This discovery much weakens the case for Archaeopteryx as an intermediate, and makes it that much more likely that the creature was just one of a number of strange birds living at that time. Professor Heribert-Nilsson commented forcefully that 'they are no more reptiles than the present day penguins with their wing-fins are transitional forms to fish'.
The 1977 discovery by Dr. James Jensen of Brigham Young University of the fossil that Hitching says looked to be the femur of a Jurassic bird, was described by professor Ostrom in the August, 1978 National Geographic Magazine, on page 167. Contrary to Hitching's claim that it was "an unequivocal bird," and that Ostrom "positively identified the specimen," Ostrom said:
I visited Jim at the quarry to have a look at his find and was impressed with its birdlike form: a hollow bone about two inches long that appeared to be part of a thighbone... Jim and I debated the creature's identity: bird? pterosaur? mammal? dinosaur?... But all we had was a fragment. Birdlike as it appeared, it could not be certified... Recently another small birdlike bone has come to light, but its identity has not yet been established.
The fossils later turned out to be from a dinosaur, as was confirmed in a personal communication with Professor John Ruben145a of Oregon State University. These fossils have not been mentioned in any technical literature since 1977. So Hitching, having published his book in 1982, was using out of date and incorrect material to prove his point. Hitching also uses an out of date quotation from professor Heribert-Nilsson -- from 1954, long before the recent paleontological work described above. So again, Hitching's argument, on close examination, falls to pieces. He neglects to mention a key point -- although each of the reptilian features he mentions can be found in other birds or bird fossils, Archaeopteryx is the only one in which all of them are found.
Hitching's final conclusion is not bad. He says:
The further point might be made that even if Archaeopteryx is in fact a half-way form from reptiles to birds, it is still not very enlightening about the process of evolution, nor in any way evidence of Darwin's hoped-for gradual transitions. For that, we would have to see in the fossil record the slow development of feathers (perhaps from scales, perhaps from some other origin) and the hierarchical change of amphibian dinosaurs into delicate, light- boned creatures that could soar above the Earth. And here, characteristically, the rocks are mute.
Actually, later discoveries of ancient birds partially salvaged Hitching's point number six. Science News, October 20, 1990, on page 246 reported the discovery in China of a 135 million year old bird fossil:
The sparrow-sized specimen is the earliest known example of a bird with modernized flying ability, reports Paul C. Sereno of the University of Chicago... The still-unnamed Chinese bird is about 10 million to 15 million years younger than the oldest known bird, Archaeopteryx, and displays several flight features that the crow-sized Archaeopteryx lacked. "This is the first bird with the capacity for a modern flight stroke," says Sereno... The fossil shows an intriguing mix of modern avian features and primitive characteristics retained from reptilian ancestors. The bird had flight-specialized shoulders and a distinctly avian adaptation called the pygostyle... The Chinese specimen... displays adaptations for tree life. The claws of its feet were long and curved, allowing the bird to perch on a branch better than Archaeopteryx, says Sereno. The "hand" bones in the wings had a shrunken first digit and an enlarged second digit, an arrangement resembling that seen in modern birds. The fossil also shows many characteristics lacking in modern birds, such as stomach ribs, unfused hand bones and a primitive pubic bone... The Chinese bird joins several slightly younger fossils found in Spain... as the only known birds from this crucial phase in avian history. Some of its primitive features, including stomach ribs, do not appear in the Spanish fossils.
Another account of the discovery, in New Scientist, November 3, 1990, in an article "Fossil birds force an evolutionary re-think," page 28, said:
The small bird... sported a breastbone, which could have anchored strong flight muscles. Sereno believes that the bird would have looked much like a modern bird... The Chinese bird retained some primitive traits, however. Its wings reveal small remnants of claws and fingers, and the bird may have had teeth. It also had stomach ribs... these are present in Archaeopteryx and carnivorous dinosaurs, but not in modern birds... fossils of perching birds 125 million years old have been found in Spain and Mongolia, but the next oldest bird fossils are about 50 million years younger.
The above mentioned Spanish fossil was reported in Science News, February 13, 1988, on page 102:
Found in the Las Hoyas limestone outcrop in Cuenca, Spain, the fossil dates back to the early Cretaceous period, approximately 120 million to 130 million years ago. The oldest bird known from the fossil record is Archaeopteryx, which has been found in 150-million-year-old formations. "The new fossil, reported here, represents a previously unknown level in the organization of birds, intermediate between Archaeopteryx and later birds," according to the discoverers of the Las Hoyas bird... Although the fossil lacks a skull, the rest of the specimen is relatively complete. The bird had primitive pelvic bones and hind limbs, but displays some more modern adaptations that are particularly important in flight. Most notable of these characteristics is a bird-like coracoid -- a bone in the shoulder that helps translate muscular force into the power stroke of a wing. And at the end of the vertebrate column, the fossil has a bone called a pygostyle, which is the skeletal basis of an avian tail. Because it combines primitive and modern characteristics, say the researchers, "the new fossil suggests that the early evolution of birds was firmly and rapidly influenced by the requirements of flight."
Discover of January, 1989, on page 63 additionally said about this fossil:
... the collarbone is strongly connected to the breastbone and is built like an airplane strut to keep the shoulders braced during flight.
The latest information on Archaeopteryx available as of this writing is from the journal Evolution. The article said:146
Although Archaeopteryx lived almost 140 million years ago (Late Jurassic Period), its avian nature is immediately evident -- several specimens are at least partially cloaked in a set of flight and contour feathers that are surprisingly similar to those of many extant birds... However, another attribute of Archaeopteryx is equally obvious: much of its skeleton is reptilian, bearing striking resemblance to a number of late Mesozoic, small bipedal dinosaurs, the coelurosaurid theropods... Interpretation of Archaeopteryx' capacity for powered flight and general mode of life has historically been the source of continuous, sharp disagreement... With a view toward reevaluation of these (and other) issues, the 1984 International Archaeopteryx Conference was convened in Eichstatt, Germany... The following scenario emerged from their debates: Archaeopteryx was an active, cursorial predator and was also facultatively arboreal; it was a glider and a feebly powered, or flapping flyer. Finally, it was incapable of takeoff and flight from the ground upward.
Because Archaeopteryx had fully developed feathers and modern-looking wings, the author disagrees with the conclusion that it was not a great flier. He proposes that it was cold-blooded, in line with its skeleton:
A new hypothesis is offered here: If Archaeopteryx retained a reptilian, rather than an avian physiology, the flight-support capacities of various internal and external structures appear far less disparate.
We have already considered most of these physical structures.
Moreover, it would have been fully capable of standstill takeoff and powered flight from the ground upward, as well as from the trees down... Just as fossilized plumage clearly signals the avian nature of Archaeopteryx' surface anatomy, a reptilian internal anatomy is suggested by its reptilian skeleton. However, in spite of its mosaic, reptilian/avian morphology, conventional wisdom holds that Archaeopteryx was functionally avian, rather than reptilian in any significant respect.
The author presents a very good explanation of the various special physical structures that birds have for flight. His main conclusion is that reptilian muscle can actually produce about twice the power per pound as compared to modern bird muscle, and therefore if Archaeopteryx had a reptilian physiology it would have been quite capable of good flight over short distances, but would lack the endurance of modern birds:
There is, however, reason to suspect that although Archaeopteryx was capable of powered flight, nevertheless, it lacked the stamina and locomotory endurance of extant birds... During "burst-level" activity, major locomotory muscles of a number of active terrestrial squamate reptiles generate at least twice the power (watts kg-1 muscle tissue) as that of birds and mammals... Utilization of high-power, reptile-type flight-muscle to support powered flight seems consistent with Archaeopteryx' relatively reduced pectoral surface area... its flight muscles would have generated comparable power, but these muscles would have required far less skeletal area for their origin. This argument would resolve much of the apparent discrepancy between external and internal flight apparatus in Archaeopteryx... Based on the metabolic physiology of a number of active modern reptiles, an ectothermic, mostly anaerobically powered Archaeopteryx would have been capable of nonstop, flapping flight ranging to distances of at least 1.5 km... This is not remarkably different from the locomotor capacity of Varanus komodoensis [the Komodo Dragon of Indonesia], which is reportedly capable of nonstop, one-kilometer sprints at speeds approaching 30 km h-1 ...
... [Reptilian physiology] would have enabled Archaeopteryx to attain powered flight and ground-upward takeoff with less than one-half the relative volume of flight musculature of modern birds. This could account for the apparent disparity between Archaeopteryx' highly developed, aerodynamic exterior, and the absence of a correspondingly developed internal skeleton typical of modern birds.
In view of all the above evidence, it is safe to summarize the knowledge relating to early birds: Archaeopteryx was an ancient bird, it could fly, and it had many reptilian anatomical features. Whether it was warm or cold-blooded is not known. Bird fossils found in later deposits show anatomical features part way between Archaeopteryx and modern birds. Archaeopteryx was intermediate in skeletal structure between dinosaurs and modern birds, and later birds were intermediate between Archaeopteryx and modern birds. No fossils of birds that had feathers of intermediate form have ever been found. This is a serious difficulty for evolutionists. Was Archaeopteryx a link between reptiles and birds -- a transitional form? The fossil evidence provides no basis for a firm conclusion.
These considerations lead to one of the most astounding aspects of life -- throwbacks. Here is what The Dinosaur Heresies had to say:147
Both Archaeopteryx and [Deinonychus] had had three fingers only -- not the five found in primitive dinosaurs. And the proportions of the fingers had been the same: A short, stout thumb and two longer outer fingers, with the outermost of the three very slender, bowed outward, and closely bound by ligaments to the middle finger. This unique pattern can still be recognized in a modern bird's wing; the three fingers are all firmly fused together in an adult bird, but in an unhatched chick, the bones are not yet fused. In a chick the separate wrist and hand bones are clearly discerned, exactly as they had been in Deinonychus and Archaeopteryx.
There exists today one species of bird that retains its finger bones unfused and flexible into the first weeks of life in the nest. This bird, the hoatzin of South America, allows us to surmise how the Archaeopteryx worked. As birds go, an adult hoatzin exhibits nothing special in the anatomy of its wing. But the young nestling is a genuine evolutionary throwback, an ugly little chick that climbs through the vegetation by grasping with its three-fingered, claw-tipped hands designed to the Archaeopteryx blueprint...
Hoatzin chicks also force a rethinking of the idea that there could be no big reversals in the evolution of birds. Evolutionary reversals unquestionably were necessary to make a hoatzin. Hoatzin's relatives all have much weaker wing claws in the chick stages of life than hoatzins themselves have. Most ornithologists therefore conclude that hoatzins evolved from some ancestor with the "normal" pattern of growth in which the chick never possesses strong, flexible, unfused fingers for climbing. According to this view, the hoatzin chick evolved by means of a Darwinian U-turn -- the strong, Archaeopteryx-like flexible fingers were recalled from genetic storage.
Genetic storage is a nuance of evolution too often ignored. Many paleontologists believe that when a bone disappears in evolution, the genetic blueprint for that bone is also erased... But in fact evolution does not occur in this fashion. Hoatzin's ancestors never lost the genetic blueprint for producing Archaeopteryx-style clawed fingers. In essence, they merely turned off the physiological switch that ordered genes to produce organs according to the encoded information. Recent advances in genetic research reveal that most species carry such blueprints that are "switched off" and can't express their code as fully formed tissue. In other words, when an organ has been "lost," most of the time its blueprint is still there, in genetic storage. Hoatzin's ancestors were "normal" modern birds that employed a modern blueprint to produce a wing in their nestlings that was like a chicken's, with stiff, fused fingers. Hoatzins evolved their distinctive Archaeopteryx-like clawed fingers by the process of turning off that blueprint for its nestling and turning back to the older one to reexpress itself.
A wealth of evidence supports this theory of reexpression by genes that have been turned off for millions of years. Most of it occurs in throwbacks (what nineteenth-century scientists called atavisms), the rare appearance of ancient organs in species that, as a whole, had lost the anatomical features millions of generations earlier. A good example is multi-toed horses. Modern horses belong to the same general group as tapirs, and tapirs have four toes on each forefoot. The single-toed modern horse evolved from a four-toed ancestor. Every so often a healthy, normal, single-toed mare gives birth to a colt that has little extra toes sticking out beside the big main toe. Zoologists point to this multi-toed foal as a case where natural processes allow a bit of the ancestral blueprint to show through, letting ancient ancestral traits reexpress themselves.
Whales offer a more spectacular case. Modern whales have no hind legs at all, and even when all the blubber and muscle are flensed from the hip region, there is no remnant of the hip bones except a small splint representing the ilium. Even the oldest-known fossil whales display only slightly enlarged hip bones and some remnants of thigh and knee. But way back in their ancestry whales did have big hind legs, at a stage when they were land-living predators. And every once in a while a modern whale is hauled in with a hind leg, complete with thigh and knee muscles, sticking out of its side.147a These atavistic hind limbs are nothing less than throwbacks to a totally pre-whale stage of their existence, some fifty million years old.
Such throwbacks even occur in human infants. Hospitals occasionally register an entirely modern-looking baby characterized by all the expected organs, plus an unexpected tail, a long, caudal appendage protruding beyond the buttocks for two or three inches. Some of these tails are even bigger than the average caudal remnant displayed by our close kin, the chimps, gorillas, and orangutans.
Genetic experiments have revealed that these throwbacks are controlled by suppressor genes. We now know that most complex pieces of anatomy -- such as the clavicle and its muscles -- are controlled directly and indirectly by scores of genes that interact and can suppress each other. We also know that the full genetic blueprint in any single species is rarely, if ever, fully expressed. Instead, much of the genetic information is stored in the "inactive file," genes that don't produce their potential impact because some other gene prevents them from turning on. When an anatomical feature disappears during evolution, its genetic blueprint is not erased. Some new combination of genes has evolved to suppress the still-present blueprint.
Birds with teeth may have appeared ridiculous to creationists, but in point of fact modern birds do carry the ancestral genetic code for making teeth tucked away in their inactive file. No living species of bird manufactures teeth. But recent surgical manipulations of bird embryos demonstrate clearly that the potential is still there. In 1983, experimenters transplanted tissue from the inner jaw (dental lamina) of an unhatched chick to an area of the body tissue, where the graft could grow. In the transplanted position, the chick's dental lamina started to produce tooth buds! Birds with teeth could grow right in the twentieth century.
Consider the above information carefully. If things like teeth can be produced in a bird embryo by simply transplanting jaw tissue to another part of the embryo, doesn't that show conclusively that the genes to produce teeth are in the embryo's chromosomes? And if whales can produce a leg, complete with muscles, in the place one would expect a leg to be if there was going to be a leg, where normally there is no leg at all, isn't that compelling evidence that the whale possesses genes for legs? And if horses every so often produce a three-toed colt, isn't that proof positive that genes for three toes are still in the horse, just as the fossil record seems to indicate? Don't these things indicate there must be something fundamental the fossil record is telling us?
In this vein The Panda's Thumb said:148
... why should the fetus of a whale make teeth in its mother's womb only to resorb them later and live a life sifting krill on a whalebone filter, unless its ancestors had functional teeth and these teeth survive as a remnant during a stage when they do no harm?
If creation really occurred, the creator may well have reused much genetic material via a mechanism like suppressor genes. It is almost as if the creator were tinkering and experimenting with life forms. After a category of animal existed for awhile, he wiped it out and started a new one, reusing some of the old parts and inventing new ones. This would explain the great variety that explodes onto the scene after each wave of extinction. It would also explain all the intermediate life forms observed in the fossil record, such as three-toed horses and birds that have reptilian skeletons and modern feathers. If these things seem too ridiculous to consider ascribing to a creator, note that apparently-reused-parts are a major reason evolutionists believe the way they do.
At this point we return to our discussion of the Creation book's treatment of the question of the change from reptile to bird. All the preceding information should allow the reader to see how poor the argument of Chapter 6, paragraph 21, is:
At one time evolutionists believed that Archaeopteryx, meaning "ancient wing" or "ancient bird," was a link between reptile and bird. But now, many do not. Its fossilized remains reveal perfectly formed feathers on aerodynamically designed wings capable of flight. Its wing and leg bones were thin and hollow. Its supposed reptilian features are found in birds today. And it does not predate birds, because fossils of other birds have been found in rocks of the same period as Archaeopteryx.12
Note the footnote number "12" at the end of the paragraph. Looking this up on page 253 of Creation we find two references. One is to an article, "Feathers of Archaeopteryx: Asymmetric Vanes Indicate Aerodynamic Function" in Science, March 9, 1979, pp. 1021, 1022. This article concluded that
the shape and general proportions of the wing and wing feathers in Archaeopteryx are essentially like those of modern birds. The fact that the basic pattern and proportions of the modern avian wing were present in Archaeopteryx and have remained essentially unchanged for approximately 150 million years (since late Jurassic time), and that the individual flight feathers showed the asymmetry characteristic of airfoils seems to show that Archaeopteryx had an aerodynamically designed wing and was capable of at least gliding. Any argument that Archaeopteryx was flightless must explain selection for asymmetry in the wing feathers in some context other than flight.
The other reference is to The Neck of the Giraffe by Francis Hitching, pages 34-35. We have already considered this reference at length. We will not insult the reader's intelligence by pointing out which details of Creation's argument are based entirely on Hitching's and are therefore irrelevant or incorrect. This is another example where the author of Creation either has not done his homework, or has avoided considering relevant evidence, and as a result has led the reader astray.
As we have already shown, the author of Creation has borrowed much material from The Neck of the Giraffe besides that on Archaeopteryx. He has also borrowed much from the "scientific creationists." It is easy to tell, because the errors in logic or in data are the same. For example, on the question of rich Precambrian fossiliferous deposits, on page 27 of his book Hitching quotes three scientists, from material published prior to 1961, as saying that there are none. Creation makes the same error. On the above question of jawbone and earbone evolution, Creation's argument is nearly the same as Hitching's, which is nearly the same as creationist author Duane Gish's in Evolution? The Fossils Say No! All err in being ignorant of the fossil evidence.
The Society leads its readers to incorrect conclusions in other articles mentioning Archaeopteryx. The July 22, 1987 Awake! has a picture on page 12 of a brontosaur and a bird, with the caption: "'Dinosaurs evolve into birds'? Consider: Birds are warm-blooded, reptiles cold..." From the information presented above, it should be evident that this presentation is a gross simplification of the actual situation and is completely misleading. It is doubtful that anyone has ever claimed brontosaurs evolved into birds.
Regarding Archaeopteryx, the January 22, 1978 Awake! said on page 24 that the "relative proportions of the head and brain case are those of a bird and are quite different from those of reptiles. So, Archaeopteryx did not evolve from a reptile to a bird." A glance at the skeletal drawings in the references mentioned above will dispel the idea that the head and brain case are very different from the dinosaurs from which birds are claimed to have evolved.
The lack of attention to detail apparent in Creation, with regard to the fossil record of the structural similarities between reptiles and early birds, is well illustrated by the two pages of quotations on pages 68-69, under the title "What the Fossil Evidence Says... about the Origin of Living Things." Under the sub-title "On Reptiles Becoming Birds" the following is cited:
"The transition from reptiles to birds is more poorly documented." -- Processes of Organic Evolution
On the face of it this quotation is taken out of context -- the transition is "more poorly documented" than what? The full context is reproduced on Part 04 of this essay, but here is one paragraph:149
The transition from reptiles to birds is more poorly documented than are the other transitions between classes of vertebrates. Nevertheless, many of the smaller reptiles in the group ancestral to dinosaurs and crocodiles had light skeletons from which those of birds could have arisen, and moreover walked exclusively on their hind legs, as do birds. Furthermore, the earliest fossil birds, from Jurassic deposits of Germany, had jaws containing teeth and forelimbs with well developed fingers... We classify them as birds because feathers are preserved with their skeletons; but if their preservation had been somewhat poorer and the feathers were not present, these animals might well have been classified as reptiles.
So the reference is not saying that the transition between reptiles and birds is poorly documented in an absolute sense, even though a strong argument can be made that it is, but that in contrast to the wealth of fossils showing the transition between reptiles and mammals, the reptile-bird transition is more poorly documented. As shown on page Part 04 of this essay, Stebbins had spent several previous pages explaining that these other transitions are quite well understood. This is not at all what Creation implies.
The other quotation under the sub-title "On Reptiles Becoming Birds" is:
"No fossil of any such birdlike reptile has yet been found." -- The World Book Encyclopedia
What "such birdlike reptile" is The World Book Encyclopedia speaking of? By putting this quotation immediately after the above cited quotation, Creation implies that it means any transitional form. The context of the quotation shows something quite different:150
Most scientists believe that birds and mammals both evolved (developed gradually) from reptiles. However, scientists know far more about the evolution of mammals. Scientists learn about the development of animals by studying fossils, especially the remains of bones. Mammals have relatively hard bones and so have left behind many well-preserved fossils. The bones of birds, however, are extremely fragile. As a result, fewer bird fossils have been preserved. This section discusses the theory that most scientists believe best describes the development of birds.
The first known birds. At some point in the evolution of birds from reptiles, there must have been various kinds of birdlike reptiles. Such creatures would have been covered with featherlike scales, rather than with recognizable scales or feathers. However, no fossil of any such birdlike reptile has yet been found.
The earliest bird fossils belong to a genus (group) called Archaeopteryx. Archaeopteryx lived about 150 to 130 million years ago. It resembled a reptile in many respects. However, it was covered with feathers and so is classed as a bird.
World Book is not saying transitional forms have not been found, but is clearly saying that fossils of birdlike reptiles with featherlike scales have not been found. Again a reference says something different from what Creation indicates.
Footnotes
73 Robert T. Bakker, The Dinosaur Heresies, William Morrow and Company, Inc., New York, 1986.
74 ibid, p. 463.
75 Stephen M. Stanley, Extinction, p. 112, Scientific American Books, Inc., New York, 1987.
76 Bakker, op cit, pp. 406-407.
77 Stanley, op cit, pp. 112-113.
78 Bakker, op cit, p. 353.
79 ibid, pp. 361-365.
80 ibid, pp. 126-138.
81 ibid, p. 462.
82 Stanley, op cit, p. 114.
83 Bakker, op cit, pp. 258-259.
84 ibid, pp. 278-280.
85 ibid, p. 363.
86 ibid, p. 292.
87 ibid, pp. 296-297.
88 John Ruben, "Reptilian Physiology and the Flight Capacity of Archaeopteryx," Evolution, vol. 45, p. 6, February, 1991.
88a Scientific American, May, 1990, page 72, said this could change: "Sankar Chatterjee of Texas Technical University in Lubbock has identified parts of fossil skeletons from much older Triassic strata in Texas as those of a bird that he calls Protoavis, but those skeletons are fragmentary and evidence for their avian nature has not yet been presented." Chatterjee published his findings in 1991, in The Philosophical Transactions of the Royal Society of London: Biological Sciences 322, #1265, (June 29, 1991), pp. 277-346. He found the fossil he informally named Protoavis in 225 million year old strata, which is about 85 million years older than Archaeopteryx. He describes the fossil skeleton as very birdlike. Some paleontologists agree with him, while others strongly disagree, pointing out that the reconstructed skeleton probably contains a mixture of bones from several individuals and even possibly from two different creatures. Most agree that the fossil, as presented, has both dinosaur and birdlike features, and unique features of its own. Zoology professor John Ruben of Oregon State University said in a personal communication that Protoavis will probably turn out to be from some sort of early ostrich dinosaur, like Ornitholestes, just as happened with fossils found by James Jensen in Utah in 1977. A discussion of Protoavis and a photo of the fossil can be found in Kings of Creation, Don Lessem, Simon & Schuster, New York, 1992, pp. 79-101.
89 D. R. Selkirk and F. J. Burrows, editors, Confronting Creationism: Defending Darwin, p. 79, New South Wales University Press, Kensington NSW Australia, 1988.
90 George Gaylord Simpson, Fossils and the History of Life, p. 180, Scientific American Books, 1983.
91 Bakker, op cit, pp. 301-303.
91a Ornitholestes was a twenty pound birdlike dinosaur built along the same lines as the better known Allosaur.
92 D. R. Selkirk and F. J. Burrows, eds., op cit, pp. 80-82.
93 Bakker, op cit, p. 305.
94 ibid, p. 458.
95 ibid, pp. 311-313.
96 John H. Ostrom, "Archaeopteryx and the origin of birds," Biological Journal of the Linnean Society, vol. 8, No. 2, p. 93, June, 1976.
97 Peter Wellnhofer, "Archaeopteryx," Scientific American, p. 70, New York, May, 1990.
98 ibid, p. 73.
99 Alan Feduccia and Harrison B. Tordoff, "Feathers of Archaeopteryx: Asymmetric Vanes Indicate Aerodynamic Function," Science, vol. 203, p. 1021, 1022, March 9, 1979.
100 Wellnhofer, op cit, p. 75.
101 Jeff Hecht, "Fossil birds force an evolutionary re-think," New Scientist, vol. 128, p. 26, November 3, 1990.
102 Wellnhofer, op cit, p. 74.
103 Samuel Tarsitano and Max K. Hecht, "A reconsideration of the reptilian relationships of Archaeopteryx," Zoological Journal of the Linnean Society, vol. 69, p. 152, 157, June, 1980.
104 Wellnhofer, op cit, p. 75.
'... Archaeopteryx did have a furcula [wishbone] like that of today's birds. In modern birds some of the pectoral muscles attach to that structure; Archaeopteryx may therefore also have had a small area of attachment for those muscles on its furcula. Its ability to fly, however, would have been rather limited.'
105 Tarsitano and Hecht, op cit, p. 152.
106 Wellnhofer, op cit, pp. 75-76.
107 ibid, p. 73.
108 Tarsitano and Hecht, op cit, p. 160.
109 Wellnhofer, op cit, p. 73, 77.
110 ibid, p. 74.
'The sternum of modern birds is a wide, arched shelf of bone that often extends from the chest to the pelvic area and serves as a protective, supportive bowl for the internal organs during flight. In the middle of the outer side of the sternum is a crest that acts as an anchoring point for the pectoral muscles. Compared with the rest of the body, the size of modern birds' pectoral muscles is unmatched by any other animal; these enormous muscles enable birds to fly by flapping their wings. There are no indications that Archaeopteryx had similarly developed pectoral muscles.'
111 John H. Ostrom, "Bird Flight: How Did It Begin?," American Scientist, vol. 67, p. 50, Jan.-Feb. 1979.
'... there is no sternum... preserved in any of the specimens... Presumably, a sternum was present in Archaeopteryx, at least in a cartilaginous state, but there is no evidence of that. What does this indicate about the size and power of the flight muscles? Perhaps nothing. After all, in bats the sternum is quite small and often lacks a keel. But the ventral flight muscle... of bats is small, comprising less than 10% of total body weight, as compared with birds, in which it typically equals 15% to 20% of body weight... Thus, the absence of a sternum in Archaeopteryx seems important -- and perhaps indicates weak pectoral muscles.'
112 ibid, p. 75.
'Instead of a sternum [Archaeopteryx] had gastral (abdominal) ribs, just as its saurian ancestors did. Gastral ribs are thin, fishbonelike braces in the abdominal area that are not fixed to the rest of the skeleton. They are found today in lizards and crocodiles and were relatively common in early reptiles and amphibious animals. The gastral ribs may have protected the abdominal area and helped to support the internal organs of Archaeopteryx, but they could not have served as points of attachment for the pectoral muscles.'
113 John H. Ostrom, "Archaeopteryx and the origin of birds," Biological Journal of the Linnean Society, vol. 8, No. 2, p. 140, June, 1976.
114 Tarsitano and Hecht, op cit, p. 151.
115 Wellnhofer, op cit, p. 75.
'In modern birds, air bags extend from the lungs into the body and reach into the bones through small openings that are usually found at the top end of the upper-arm bone. These air bags enhance the capacity to breathe and help the bird to meet its heavy oxygen requirements during flight. Archaeopteryx lacks openings for air bags in its bones; therefore, it is questionable whether the animal had birdlike lungs.'
116 Tarsitano and Hecht, op cit, p. 157.
'It is unknown whether the bones of Archaeopteryx were pneumatic.'
117 Ostrom, op cit, p. 135.
118 Wellnhofer, op cit, p. 75.
'The largest feathers of the manus [hand] originate from only the middle finger; the largest feathers of the arm come from the ulna, the largest bone of the lower arm. Yet the ulna is smooth, in contrast to that of modern birds, which has small knobs where the main feathers are anchored firmly to the bone by ligaments. It therefore seems that the main feathers of Archaeopteryx were not anchored in the skeleton.'
119 John H. Ostrom, "Bird Flight: How Did It Begin?," American Scientist, vol. 67, p. 50, Jan.-Feb. 1979.
'Another surprising feature of the skeletal "flight apparatus" of Archaeopteryx is the shape and thin sheetlike construction of the coracoids -- the robust strutlike bones in modern birds that brace the shoulder against the breast bone. This coracoid brace is critical in flying birds, because it immobilizes the shoulder socket so that the full contractile force of the flight muscles is applied to the power stroke of the wing, and there is no loss of muscular force by downward displacement of the shoulder. In Archaeopteryx the coracoids are thin, half-moon-shaped sheets of bone -- short in length and not at all robust -- fragile "braces" (?) between the shoulder and the sternum. This too suggests that the pectoral region was subject to relatively weak stresses resulting from relatively small "flight" muscles.
'Even more interesting is the absence of the triosseal canal..., the pulleylike structure of the shoulder skeleton in modern birds that reverses the action of the suprocoracoideus muscle so that it powers the wing recovery stroke, rather than adding to the downward power stroke. Without that canal, this muscle could not possibly have functioned to elevate the wing in Archaeopteryx, and the recovery stroke must have been powered by the relatively weak and mechanically less efficient dorsal muscles, such as the deltoids.'
120 Wellnhofer, op cit, p. 75.
'... the bones in the manus [hand] of Archaeopteryx are not fused to support the wing as they are in modern birds. Its fingers could move independently of one another and were equipped with strong, pointed claws.'
121 ibid, p. 75.
122 Ostrom, op cit, pp. 124-130.
123 Tarsitano and Hecht, op cit, p. 171.
'... Archaeopteryx depicts a mosaic of advanced bird-like muscular features and primitive archosaurian attachment points.'
124 Wellnhofer, op cit, pp. 75-76.
'The foot of Archaeopteryx is definitely adapted to running and has features intermediate between those of reptiles and modern birds. In reptiles the metatarsal bones in the foot are separate; in modern birds these bones have fused into a single bone. Overall, the foot structure of Archaeopteryx, like that of its theropod ancestors, is birdlike, with three long toes and a short backward-facing toe. The sharp, bent claw on the backward facing toe suggests this prehistoric bird might have been able to grasp objects with its feet and perch on a tree branch.'
125 Bakker, op cit, p. 319.
'[John Ostrom] had observed that Archaeopteryx's foot couldn't get the same grip on a branch as can modern birds. Climbing birds have an inner toe that faces backward and flexes forward to grasp a branch against the other three toes. For the most efficient performance, all four of these toes must be long and their base joint must be at the same level, located at the very bottom of the long ankle bones (metatarsals). Archaeopteryx's foot was not so built. The toe facing rearward was too short and too high up on the ankle, so that its grip on a branch wouldn't be anywhere near as effective as a modern bird's... even though Archaeopteryx's foot didn't have as precise a grip as the most specialized modern perching birds do, it did have as much grasping power as many modern birds that climb adequately. And Archaeopteryx wouldn't have had to rely on its hind feet alone for effective climbing because its wings also had hooklike claws. Archaeopteryx certainly could have clambered through the ancient Bavarian vegetation as efficiently as any hoatzin chick. Finally, if Archaeopteryx were a ground jogger, its hind claws would have been blunt like those of a modern ground bird. In fact, the Archaeopteryx's feet ended in needle-sharp claws. And if it had run about on such pointed hind claws, it would have worn down their horny outer sheath. Yet the fossils display hardly any wear even on the delicate points of the claws.'
126 Wellnhofer, op cit, p. 72.
127 Ostrom, op cit, p. 109.
See photos and drawings on pages 110 and 115. Page 109 states: 'Although sometimes described as "bird-like", the hand and forelimb of Archaeopteryx actually are not like those of modern birds at all, but they are remarkably similar in a number of details to those of certain small theropods, namely Ornitholestes, Deinonychus, Velociraptor...'
128 Bakker, op cit, pp. 312-316.
Compare the drawings of the hands of the hoatzin adult, hoatzin hatchling, Archaeopteryx, and Deinonychus on page 313. The July 8, 1986 Awake!, page 23, said about the unusual hoatzin: 'If the adult hoatzin is unusual, baby hoatzin is even more singular. When hatched, out comes a naked chick armed with a strong beak and oversize feet. But puzzle for a moment at the well-developed claws, or "fingers," at the bend of each wing, much like our thumb and forefinger. E. A. Brigham, who studied them a century ago, exclaimed: "From an egg laid by a bird with two feet and two wings comes an animal with four feet."... On all fours they scramble among the branches and vines, using their parrotlike jointed beak, big clawed feet, and powerful wing hooks. Good climbers, all right! But the "hands" also make effective "paddles."'
129 Tarsitano and Hecht, op cit, p. 163.
'The similarity of the humerus and its deltoid ridge in Archaeopteryx and theropods is not a synapomorphy but the plesiomorphic condition found in most archosaurian reptiles, such as crocodilians and thecodonts. The avian humerus is characterized by the axis of the capitellum and trochlea being almost at right angles to the long axis of the head of the humerus. The condition in Archaeopteryx is primitive and non-avian.'
130 Ostrom, 1979, op cit, p. 50.
'... the humerus lacks all the other processes and tubercles that are prominently developed in modern flying birds and that are the sites of attachment of the special muscles that fold the wing compactly against the back and flanks.'
131 Wellnhofer, op cit, p. 75.
'The underdeveloped pectoral muscles, the reptilian lungs and the lack of firm anchoring for the main feathers all paint a picture of Archaeopteryx as a poor flier. Nevertheless, the perfectly developed plumage of Archaeopteryx makes it certain that the animal did fly. No other vertebrates besides birds are equipped with real feathers...'
132 Bakker, op cit, p. 319.
133 Wellnhofer, op cit, p. 72.
134 Bakker, op cit, pp. 258-259, 363.
135 Tarsitano and Hecht, op cit, p. 162.
This reference agrees that the hand and wrist structure of Archaeopteryx was quite similar to that of various small theropod dinosaurs, as described above, but attributes them to "parallel evolution" rather than direct descent.
136 Ostrom, 1976, op cit, p. 109.
137 ibid, p. 170.
138 Wellnhofer, op cit, pp. 73-74.
139 ibid, pp. 73-74.
140 ibid, p. 70.
One person commented:
Neither Fred Hoyle nor Chandra Wickramasinghe has a clue about biology (their acknowledged fields are astronomy and mathematics respectively). Note that the origin of life on earth is completely separate from the evolution of life (the latter obviously presupposes life exists but does not even try to say anything about how life started).
Fred Hoyle created a recent flap by claiming that Archaeopteryx was a forgery (his claim has since been shown to be false and based on an abysmal ignorance about fossils). Creationists actually flew Chandra Wickramasinghe to the 1982 "Balanced Treatment of Creation-Science and Evolution-Science Act" trial held in Little Rock Arkansas (as their star witness!). Unfortunately, their moronic scheme back-fired in a very large and humorous way. When cross-examined about the young earth creationist notion that the universe was 10,000 years old, his reply was "one would have to be crazy to believe that". Could any rational scientist believe that the earth's geology can be explained by a single catastrophe? "No." Could any rational scientist believe that the earth is less than one million years old? "No." Wickramasinghe's firm understanding of biology was brought forth by asking him to read a passage from [Hoyle and Wickramasinghe's book] Evolution From Space which claimed that insects are in fact smarter than humans but are being very careful to not let on. These statements ended up completely undermining the case of the team who paid his air fare. Judge Overton expressed confusion as to why the defense recruited Wickramasinghe; he ended up assuming that it must have been because Wickramasinghe was critical of both evolution and the scientific community.
141 Tarsitano and Hecht, op cit, p. 177.
142 Wellnhofer, op cit, pp. 74-75.
143 Ostrom, op cit, p. 170.
144 John H. Ostrom, "A New Look At Dinosaurs," National Geographic Magazine, vol. 154, No. 2, p. 168, Washington, D.C., August, 1978.
145 Hitching, op cit, pp. 34-36.
145a Professor Ruben published an article "Reptilian physiology and the flight capacity of Archaeopteryx" in Evolution, vol. 45, pp. 1-17, February, 1991. Ruben said in a telephone conversation April 22, 1991 that Professor Jensen's find "was a joke, it was probably from one of the ostrich dinosaurs and was certainly not an early bird."
146 John Ruben, "Reptilian Physiology and the Flight Capacity of Archaeopteryx," Evolution, vol. 45, pp. 1-17, February, 1991.
147 Robert T. Bakker, The Dinosaur Heresies, pp. 314-316, William Morrow and Company, Inc., New York, 1986.
147a Science magazine, 13 July 1990, Vol. 249, pp. 154,156, in an article "Hind Limbs of Eocene Basilosaurus: Evidence of Feet in Whales," said: "Hind limb buds have long been known in embryonic cetaceans up to 32-mm crown-rump length (6), and adults with externally projecting rudiments are also known (7)." Reference (7) said: "The rudimentary limb described by [R. C.] Andrews [in 1921] was said to include a femur, tibia, tarsus, and metatarsus; only two were ossified, and these are best interpreted as a femur and tibia with intervening connective cartilage. Tarsal and metatarsal bones are not found in extant whales." In other words, the limb contained upper and lower leg bones, and cartilage corresponding to partially formed feet and toes.
148 Stephen Jay Gould, The Panda's Thumb, p. 29, W. W. Norton & Company, New York, 1980.
149 G. Ledyard Stebbins, Processes of Organic Evolution, p. 146, Prentice-Hall, Inc., Englewood Cliffs, New Jersey, 1971.
150 The World Book Encyclopedia, Vol. 2, p. 369, 1990.
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