Posted by jlwile on July 27, 2010
An article in Science Daily reports on a study that supposedly answers the question, “Which Came First, the Chicken or the Egg?” Unfortunately, while one of the authors gives the correct answer (the chicken), he doesn’t use the correct reasoning. Also, spending time on that question actually distracts from the amazing results of the study, which demonstrate the incredible design ingenuity of the Creator.
The study focuses on chicken eggs. Specifically, it focuses on the shells of chicken eggs. While you and I (and a baby chick) see the shell as something annoying that needs to be broken, it is actually a marvelously-constructed shield that protects the contents of the egg while allowing them to interact safely with the environment. After all, the contents of the egg need protection, but the embryo needs oxygen, which it must get from the outside world. The egg shell is strong enough to protect the egg’s contents, but it is also porous enough for oxygen (which the embryo needs to take in) to diffuse into the egg and carbon dioxide (which the embryo must expel) to diffuse out.
This marvelous shell is made of a combination of proteins and calcium carbonate crystals. The proteins provide a bit of flexibility, while the calcium carbonate crystals provide strength. Without the proteins, the shell would be too brittle, and without the calcium carbonate, the shell would be too weak. The mother chicken makes both the proteins and the calcium carbonate, but until the study mentioned above was published, there was a big question mark regarding exactly how the calcium carbonate portion of the egg shell was formed.
You see, the calcium carbonate in an egg shell is in the form of crystals – solid structures in which the ions (charged atoms) that make up the structure are arranged in a long-range, repeating pattern. This gives the calcium carbonate the rigidity it needs to provide strength to the shell. However, that’s not how the mother chicken produces it. She can’t make crystals, so she makes amorphous calcium carbonate, which has no long-range repeating pattern in the layout of its ions. In order to make a proper egg shell, the amorphous calcium carbonate has to be transformed into calcium carbonate crystals. It turns out that’s where the real engineering comes in.
In the study, the authors looked at a protein called ovocledidin-17 (OC-17). It is found in egg shells, and it was always assumed to play a role in the formation of calcium carbonate crystals. Using the known structure of the protein, the authors used supercomputer calculations to show that the protein grabs a bit of amorphous calcium carbonate and clamps down on it, encouraging its ions to form the orderly structure necessary to turn it into a tiny crystal. At that point, the crystal forms what chemists call a “nucleation site,” which can then attract more ions to continue its orderly structure. In essence, once the protein forms the tiny crystal from calcium carbonate, the protein’s job is done, because that crystal can then grow on its own by just collecting more ions.
Now here’s the tricky part – the protein is attracted to calcium carbonate, and it is everywhere in the egg shell. Suppose the protein kept going back to the same crystal, continually clamping down on it. That would take it away from other bits of amorphous calcium carbonate that need its help to start the crystallization process. So…how does the protein know what it should clamp down on and what it should ignore? As you would expect from any well-engineered system, the protein looks at the size of the crystal to determine what it should do. If the crystal is large enough to grow on its own, the protein doesn’t clamp down on it. It “sees” that the crystal doesn’t need its help, and it moves on. If the calcium carbonate is not in the form of a crystal that is big enough to grow on its own, it clamps down to transform it into such a crystal!
Now this might sound like common sense, but that’s just because you can think through the issues involved and come to the same conclusion that any intelligent designer would reach: the protein should spend its time on crystals that need its help. However, in order to do that, the protein must be built with exactly the right structure – one that can not only do the job it is supposed to do but also gauge whether or not to spend time on a particular job. That makes for a very sophisticated protein, indeed. As the author of the Science Daily article says:
The researchers had therefore uncovered an incredibly elegant process allowing highly efficient recycling of the OC-17 protein. Effectively it acts as a catalyst, clamping on to calcium carbonate particles to kickstart crystal formation and then dropping off when the crystal nucleus is sufficiently large to grow under its own steam. This frees up the OC-17 to promote more yet more crystallisation, facilitating the speedy, literally overnight creation of an egg shell.
This “elegant process” is just one of many, many examples of design that we see in nature. From amazing biological systems to the incredible chemical systems that run them, the natural world is filled with instances of breathtakingly elegant design, which clearly testify to the design ingenuity of the Creator who produced it all.
Now…since the Science Daily article distracts from this issue with the Chicken and Egg question, I need to comment on that as well. We know the chicken came first, because God first created, and then His creation was fruitful and multiplied. Does this mean the author’s conclusion supports the creationist view? Definitely not. Indeed, all it does is show the author’s ignorance regarding some of the basics of the evolutionary hypothesis.
The author claims that since the OC-17 is made by the mother chicken, and since it is necessary for the formation of an egg’s shell, the chicken must have come first in the evolutionary process. Otherwise, the egg wouldn’t have a shell and wouldn’t survive. However, from an evolutionary point of view, that’s not the case at all.
First, evolutionists rely heavily on the hypothesis of co-option, where a protein that is used for one process is somehow co-opted and used for a completely different process. It could be that the evolutionary ancestor of the chicken made OC-17 (or something similar to it) for some other purpose, but when it the right number of mutations and other changes occurred in order for the ancestor to produce a chicken embryo, the OC-17-like protein got co-opted to form calcium carbonate crystals for the egg from which the first chicken would hatch. Most likely, the crystal formation was not nearly as “elegant” as it is today, but over time, mutation and natural selection would “tinker” with the protein until it became the marvel that it is today.
Second, there is no evolutionary reason to suspect that the first chicken egg was covered in a calcium-based egg shell. Indeed, if chickens evolved from some small dinosaur, it is possible that the first chicken hatched from an egg with a leathery egg shell, like the shell that covers the eggs of modern reptiles. Then, over time, the chicken could have developed a calcium carbonate egg shell (along with the OC-17 needed to produce it) due to many fortuitous mutations that were operated on by natural selection.
From an evolutionary standpoint, then, this study says nothing about the chicken and egg question. That’s not a big deal, however, since the evolutionary hypothesis is not very scientific. From a scientific standpoint, we know that the world was created, and thus the chicken definitely came first. The scientific part of the study (the analysis of OC-17) just provides more evidence for the fact that the chicken was created.