Dr. John Ankerberg: Dave, you have done research into feathers. What did you find?

Dr. David Menton: I have a sort of hobby and a layman’s interest in feathers, and indeed, in birds in general. It may come as a surprise to a lot of people that birds have, in fact, left a rather reasonable fossil record. Now, we’re not just talking about archaeopteryx that is speculated to be the first bird. Some would argue that there are even substantially older birds found in the record. However, that’s debated.

In any event, it may come as a surprise that the birds have left a fossil record. I understand that there is something well in excess of 8,000 species of birds in existence today, and that approximately 2,000 species of birds have been found in the fossil record. Now this may be just a fragment of a bone, it may be an egg, or a portion of an eggshell, it could be a single feather, but nonetheless approximately 2,000 species of birds are there.

Usually fossils are skeletal parts. These are the hardest parts and I guess the reason it’s surprising to find so many bird fossils is that the bird skeleton is very light. It’s a very unique skeleton in that respect. The skeleton, indeed the whole bird appears to be an animal that has been formed to fly. To give you an idea how light the skeleton can be in a bird, the frigate bird, which has a 7-foot wingspan, has a skeleton that weighs the grand total of 5 ounces. This is less than the feathers of the bird would weigh.

Now, evolutionists perhaps are as confident regarding the origin of birds and by implication of the origin of feathers, which I really want to focus on, as they are about anything. They’re quite confident that birds evolved 150 million years ago in the Jurassic. There is some difference regarding what particular reptile they may have evolved from. The Pygopodid reptiles rank high in that category. And because there’s a great deal of confidence that birds evolved from reptiles, there is then by implication confidence that the feathers of a bird evolved from the scales of the reptile, both being, as it were, cutaneous appendages. This has led, I think, evolutionists to be somewhat less than objective, at least some of them, regarding the assumed relationship of feathers and reptilian scales. They have emphasized that the two are not very different.

Let me give you a specific example. Gerhard Heilmann in his classic work called The Origin of Birds, said, "The most striking peculiarity of birds is their plumage, which apparently has nothing to do at all in common with the scaly covering of reptiles. So much more surprising is it on examining these expressants microscopically, to learn that the feather is nothing but a further development of the scale." Indeed, he said that the feather may be considered a cylindrical, fringed scale. This has led to a great deal of speculation of how a scale could perhaps get longer and become frayed and eventually form a feather.

I would ask the readers to look at the evidence for a fossil bird to see the evidence for feathers in the earliest known bird, according to evolutionary views, and decide for themselves whether, in fact, there is an evolutionary precursor for the feather—and I submit there is none—and whether reptilian scales, at least as they exist today, and bird feathers as they certainly existed in archaeopteryx, are, as Heilmann says, not very different.

According to some evolutionists, archaeopteryx would be the world’s first bird, approximately 150 million years old. There are six or seven fossils identified as archaeopteryx. Some of the fossils are just merely feathers. Two have particularly good skeletal component as well as feathers.

A distinctive feature of birds is the wishbone, as everybody knows who has broken a wishbone at Thanksgiving dinner. And archaeopteryx, like other birds, does have a wishbone. And as far as I know this is unique to birds. It’s a fused collarbone, and the fused collarbone helps to support the shoulder girdle in flight. Immense forces are brought to bear on the shoulder in flight.

The important thing about the archaeopteryx fossil is that we can see feathers. We see feathers in the wing, feathers in the tail, and in fact, there’s evidence that there are even small contour feathers on the head, even though archaeopteryx is often shown with a scaly head, trying to emphasize its similarity to reptiles.

The feather of a bird has a shaft running down the center. It has a feather vane on either side, and this vane is made up of approximately 400-600 barbs that hook together to give the feather its sort of airplane wing shape.

Feathers are essential for avian flight. They are under control of muscles so that they can be tilted in flight to increase lift, they can open and close rather like Venetian blinds in flapping flight, so that on the upstroke wind can be allowed to pass through the feathers of the wing and on the down stroke the Venetian blinds can close as it were and give a power stroke in flapping flight.

As I say, feathers are unique to birds. They are not found among reptiles, certainly not among living reptiles. And the question is, are they similar to the reptilian scales? I submit that they are not similar in any sense of the word.

If you look at a feather under a scanning electron micrograph, you will see a shaft running upward through the middle of the feather, the vane on either side, and the barbs, which comprise the vane of the feather. Each of these barbs, if it were removed, would look like a small feather in its own right.

When one looks at a reptilian scale, one does not notice an obvious similarity between feathers and reptilian scales. Indeed, developmentally (that is, not in an evolutionary sense, but in terms of embryologic development and in terms of the development of the adult as the scales are shed or as the feathers are shed), there is no similarity in the developmental pattern of a feather and a scale.

A feather grows out of a follicle, much as a hair grows out of a follicle, whereas a scale is a more like a fold, a full-thickness fold, in the surface of the skin and is not a follicular structure.

If you look at a scale from below, you will see that it looks like a little coin purse, or a flap. This is why we say that the scale is really a fold in the skin and not a structure that grows out of the tube-like follicle, as does the feather and the hair. There are scales that are pointed on the end, but there are no scales that we know of that have anything resembling barbs, making up something like a feather-vane.

There are really three different types of feathers. First, we have the so-called contour feather, which is the principle feather of the bird. You find it on the wings and on the body. Then we have the down-feather, which looks kind of like a ball of fuzz. The down-feather comprises an under-plumage of the bird that serves for insulation. And finally, we have a very fine feather called the filoplume. These are small hair-like feathers. If you’ve plucked a chicken, you’ve probably noticed the little hairs protruding from the skin and these particular feathers are believed to be proprioreceptors. That is, because the individual feathers are movable, particularly the flight feathers in the wing, you need a way for the bird to know what position the feathers are in at any given time as they’re tilted, to produce slot-like effects. And the presence of the filoplume apparently gives some feedback to the nervous system of the bird regarding the status of its feathers.

Let’s look at the feather in more detail. The down-feather has a shaft similar to the contour feather. However, instead of having a flat vane on either side of the shaft, the individual barbs are separate from one another and are not hooked together to form an airfoil.

Next, the contour feather. If we were to remove individual barbs we would see that each barb of a vane looks like a microscopic feather in its own right. Indeed, each of these barbs has approximately 800 barbules, which are like miniature barbs, that protrude both anteriorally toward the tip of the feather and posteriorally toward the base of the feather. It is these barbules that interlock with a Velcro-like hook mechanism that hooks the feather together.

Anyone who has taken a feather knows that you can pull a vane apart, and by stroking the feather—and birds do the same sort of stroking with their beak—you can cause a torn feather to rehook or reattach. So it is the presence of approximately 20 tiny, little hooks sometimes called barbicels, on each barb that locks the barbs together to form the vane.

If we pull this feather apart so we can look down inside a little more, we can see the barbs crossing one another, and we see the individual hooks, which look like a little cane protruding. These hooks attach to a little trough that runs along the so-called posterior barb and the radius of curvature of the hook just precisely fits the radius of curvature of the little trough that it needs to hook to. So it is approximately 700 billion barbicels that are on the whole bird that need to be hooked in place to hold the feathers together. And as I say, this is a rather Velcro-like arrangement that allows a very light and yet very strong structure that we call a feather.

I might point out that the entire feather structure is dead, just like a hair, and that it is full of a product called keratin, which of course occurs in human skin and hair as well. And so the cell started out alive but gorged itself with keratin, went through a program cell death, so that when the feather emerges from the skin, like a hair it is a entirely dead structure. It’s like building a ship in a bottle.

The feather grows out of a "tube," rather like squeezing toothpaste out of a tube except, as the toothpaste emerges it hardens, because it dies. The keratin becomes very substantial and strong. The feather emerges from the skin, although down in this tube-like follicle, all of the components of the feather develop from living cells.

Down at the bottom of this tube that we call the feather follicle in the skin, is a ring of cells that grows not only the shaft along one side, but the barbs as well. And this is all rolled into a tube much like a mailing tube. The shaft of the feather runs down one side; there is the growth zone along the base; and the individual barbs are protruding at a steep angle on both sides. The entire structure is rolled into a cylinder and meets on the other side.

The feather then grows out of the skin looking like a thick hair. A shell breaks off the surface of the feather, the cylinder opens up and the individual barbs all hinge down, thus substantially increasing the width of the feather.

It’s in this sense that I say making a feather down inside of a follicle is like a rather extreme case of building a ship in a bottle, then pulling the ship out of the bottle and having all the rigging finally stand up and everything lock into place. Usually, we build the ship outside the bottle and then put it in. All of this is produced, as I say, from living cells, which go through programmed cell death to form a feather.

Nothing remotely like any of this occurs in the reptilian scale. There is no development similarity whatsoever. The only thing we can say that the two would share in common at all is that both are made out of a protein or actually a large family of proteins that we call keratins.

There is no evidence of a pre-feather. Archaeopteryx comes packaged with perfectly modern type feathers. The material in which the fossil has been formed in the case of archaeopteryx, is of such fine grain that it has allowed us to actually see the detail down to the level of the barbs and hooks. And all of this suggests then, that archaeopteryx had a feather structure that was not significantly different from that of modern birds.

More importantly, the feather that exists on archaeopteryx, particularly in its wings, is the type of feather that we associate with flying birds. That is, it is an asymmetric feather vane, one vane is narrower than the other. In birds that do not fly, but hop along the ground, such as the chicken, the two vanes of the feather are approximately equal. But in the flight feathers of the birds that are powerful fliers, one vane on the wing feather would be much narrower than the other vane.

This is the type of feather that we see in the wing of archaeopteryx. All of which is consistent with the idea that archaeopteryx was a bird. It had a wishbone, or fused collarbones, like a bird, and does not then represent an intermediate form between reptiles and birds. Rather, it is an interesting bird that is extinct and bears features we no longer see in modern birds, although the digits on the hand of the wing is seen in some modern birds.

All of this is consistent, I believe, with the creationist point of view that birds, like bats and many other organisms, appear suddenly in the fossil record without known ancestral forms. This certainly is true of feathers.

I mentioned, I think, that there are some scales that do have a little ridge on their surface, that is instead of being discoid, there would be a little dorsal ridge. Sometimes this ridge protrudes as a point. But it requires a great deal of credulity—certainly much more than I have—to believe that this scale can be gradually transformed by increasing its length beyond that which we see in reptiles into an ever longer keratinized form and that this rod-like structure protruding from a scale could then develop lateral rods that would form the barbs of the feather and that these barbs could form hooks. Certainly nothing even closely approximates that structure on modern reptiles or fossilized reptiles.

The feather and the scale are greatly dissimilar structures, but the feather and the hair are similar in many important respects. Now, why don’t the evolutionists focus on this fact? That, for example, the feather grows out a tube-like follicle in the skin, the hair grows out of a tube-like follicle in the skin. All of the growth matrix where the cells are dividing in the feather is confined to a little dermal papilla down at the bottom of the feather and the same is true of the hair.