If we open any tenth grade Biology book we will face a chapter called "Evidences for Evolution." Do evidences for evolution really exist? Let's study some of these evidences and check to see if they are truthfully reliable.
COMPARATIVE ANATOMY
The similarities in anatomy between various forms of animals are considered as one of the strong supports for evolution. For example, when we compare the wing of a bird, the fin of a dolphin and the arm of a man, we will see that even though they are very different, they have very similar bone and muscle structures. The evolutionists look at these structures and say they came from a common ancestor, through inheritance of a basic plan of body structure. The creationists, on the other hand, look at these same evidences and say they are the results of a Designer using a common plan. The data are consistent in every respect with the paradigm that an intelligent Creator made the systems of the various vertebrates. He developed a general flexible plan that could be adapted to each one of their needs. The evolutionist must assert that all of these characteristics developed through random mutations and natural selection. The creationist explains them as structures that were received from the Creator with special functions directed toward specific goals. When similar goals were required (flying or swimming), similar structures (wings or flippers) were created.
COMPARATIVE EMBRYOLOGY
If we compare the embryos of certain kind of animals, we will see that there are similarities among them, and these similarities are even greater than the ones found in the adult forms.
Even at the time of Darwin, evolutionists suggested that the similarities in embryos’ development indicated a common ancestry. Some modern textbooks still show pictures of embryos of fish, amphibians, birds, reptiles and mammals together with those of man, emphasizing similarities among them and presenting these similarities as evidence for a common ancestor for these diverse forms.
The well-known evolutionary phrase "ontogeny recapitulates phylogeny" is a popular definition of the "recapitulation theory" or "biogenetic law" of Haeckel. He stated that each organism in its embryonic development (Ontogeny), has a tendency to recapitulate the stages through which their ancestors passed (Phylogeny). In the case of man, for example, it was taught that the human embryos began life as a marine protozoa, developed in a aquatic environment until it became a worm with a tubular heart, then a fish with gills and a heart with two chambers, after that it became an amphibian with a heart of three chambers and a mesonephric kidney, and then a mammal with a heart of four chambers, metanephric kidney and a tail, and finally a human being. In this way, the human embryo retained "vestiges" of its evolutionary history, recapitulating its main phases.
The most famous of these parallels was undoubtedly the supposed development of gills in the “fish stage” in the growth of the human embryo. This supposed recapitulation was entirely superficial; the human embryo never develops gills or anything similar to them, and therefore it is never a fish. In fact, both the man and all of the chordates develop pharyngeal "pouches" with pharyngeal sacs. In fish they latter become the gills. In humans beings they become the Eustachian tubes, the parathyroid glands, and the thymus. While they are developing, they serve as essential guides for the development of blood vessels, and in this way, are in no wise, useless vestiges.
Haeckel’s belief that each embryonic stage represents the adult stage of one of its ancestors is considered to be completely wrong by modern embryologists. Today evolutionists accept that developmental patterns in a close group of animals might contain aspects that reflect its past, but many innovations are overlaid and frequently make the ancestral pattern obscure. Thus, there is no precise recapitulation. It is surprising that some prominent evolutionists still continue to refer to this idea as an evidence for evolution. However, those that have an up-to-date knowledge, in embryology as well as in paleontology, do not.
If, for evolutionists, the similarities in embryology are evidences of common ancestry, for Creationists, they just make evident the common design of the Creator. From the Creationist premiss, because chordates (fishes, amphibians, reptiles, birds, and mammals) would have the task of reproducing its species by the same reproductive process, it would be expected that the development would be similar in all these animals.
The embryonic animal begins its existence with the fusion of two gametes, and after this fusion happens a multiplication of cells that must take place for a certain time in the same kind of environment. Furthermore, many of the structures that are to develop have to be similar in a general sense (limbs, head, etc.). Taking this into account, it would be natural that embryos would be very similar in early stages of development.
In this period, however, as the specialized traits that correspond to the progenitor species become necessary to be formed, these superficial similarities give way to the distinct and appropriate embryonic characteristics. In fact, these important differences begin to show in a very early embryonic stage of development.
There are also, even in the early stages, differences between embryos that are as important as the similarities. The DNA of a bird is quite different from the DNA of a reptile. The distinct genetic material, programmed for each animal species, assures that only that species will develop from that embryo.
COMPARATIVE BIOCHEMISTRY
The recent advancements of Molecular Biology have made possible to compare directly the genetic structure from different species, through the comparison of the sequence of nucleotides of the DNA molecule. Other chemical compounds present in living beings have also been compared, especially proteins like gamma globulin, insulin, cytochrome C, hemoglobin and others. In general (however with many exceptions) the similarities of these biochemical systems align almost in the same way as the similarities traditionally based on the anatomic characteristics and the other morphologic traits. That is, animals that would have several anatomic similarities, in general, also have DNA and proteins that are very similar. This should be an expected fact, knowing that the DNA is responsible for protein synthesis of a given organism, and the proteins, in an ultimate sense, will be responsible for the phenotypic traits of the organism.
Doubtlessly, this is exactly what one should expect having as paradigm the Creation model; compared biochemistry can be used as evidence for evolution and as evidence for the common design of a Creator.
VESTIGIAL ORGANS
Vestigial organs are present in man as well as in other animals, and are considered useless vestiges of structures that were useful in former stages of development. In the turn of the twentieth century, a long list was made of vestigial organs in mammals. This list was considered to be a compelling evidence of macroevolution. The list consisted of more than 80 organs, which included such as thyroid, thymus, pituitary glands, olfactory bulb, middle ear, tonsils and appendix. Today it is common knowledge that all these organs have useful functions, and not infrequently, essential. But in the time the list was made, nobody knew their function. As studies were developed by physiologists, the list started shrinking. Presently, it has been shown that the majority of the so called vestigial organs, especially in man, has a definite use and is not, in any sense, atrophied.
The logic used to determine whether or not an organ is vestigial should be carefully analyzed. If we don’t know the function of something, it is automatically a candidate to be a vestigial organ. The weakness of the argument, however, is that the more we do research, the greater the chance that we will learn the functions to the supposedly vestigial organ.
The human appendix was commonly removed in surgeries by physicians, for it seemed to lack function and it would frequently cause problems. Today we know that it is part of the immune system. It is true that disease sometimes happen in the appendix, and, when it becomes infected, it must be removed. However, the person would be better off by keeping the appendix.
Could it be that the fused vertebrae in men are useless? Actually, this little structure has a very important function as the connecting point to the muscles that allow us to stand up (and that provide cushioning when we sit down). In no way they can be considered vestigial. The embryological pathway that renders a tail in other mammals, produces in us an important structure. Did that happen by evolution or was it planned by a Creator?
The segmented muscles in the abdomen are important for bending the body and for maintaining tonus of the abdominal wall. That these muscles came from a common ancestor is pure conjecture, and is not evidence for or against evolution or Creation.
Why there are muscles attached to our ears? Some people desired to call them true vestiges, whereas others say that they give a certain shape to our heads or sustain the ears. More information is necessary for a decision to be made.
The posterior limbs of whales are isolated bones that are immersed in the tissue. They are considered by evolutionists as vestiges of true posterior limbs that would have existed in the terrestrial ancestors of the whales. Nevertheless, they have a very definite function: they are the attaching point for the muscles of the reproductive system. Creationists can argue that God modified the genetic instructions of the posterior limbs to produce these structures that serve for a unique function.
FOSSILS
Fossils are remains of vestiges of beings that lived in the past. A fossil is formed when the death remains of an organism are kept safe from the action of the decaying agents, as well as from weathering (wind, sun, rains, etc.). The most favorable conditions to fossilization happen when the body of an animal or a plant is buried in the bottom of a lake a rapidly is covered by sediment.
Depending on the acidity and of the minerals present in the sediment, different processes of fossilization may happen. Permineralization, for instance, is the filling up of the microscopic pores of the body of a being by minerals. Substitution, on the other hand, consists of the slow exchange of the organic substances of the carcass for minerals, turning it into stone.
Fossils are considered evidence of evolution because they show that our world has been inhabited by different beings than those that live today and that they would be the ancestors of the modern forms of life.
However, there are some serious problems with fossils in the field of the theory of evolution. Let’s take a look at some of them.
It is interesting that the same abundance of similarities and of differences is found in same extent in living creatures as in fossils. The same kinds of gaps between species that exist in the fossil record also exist today among animals and plants. If the evolutionist model were valid, it would be predictable to find a continuous and horizontal series of organisms instead of definite categories.
One of the most important fossil gaps is the one existent between the microorganisms like blue algae and bacteria found in the Precambrian strata and the abundant and complex invertebrate marine life found in the Cambrian. In the Cambrian we find a great variety of very complex invertebrates, such as trilobites, sea urchins, sponges, jellyfishes, crustaceans, brachiopods, mollusks, and worms. If evolution really happened, we should find in the Precambrian the evolutionary ancestry of all these animals. However, in the Precambrian rocks we find only fossils of microorganisms. If we find fossils of bacteria, we most surely should be able to find the ancestors of the Cambrian animals. If the former indeed evolved and became the latter, it seems impossible that no transitional forms have ever been found. For over 150 years there has been an intense search, but none of the ancestors has been found.
This phenomenon has been called by Gould the “Cambrian Explosion”. Recently, the estimated time for the occurrence of the “explosion” was revised downward from 50 million to 10 million years – which is equivalent to a blinking of an eye in geologic terms. This shorter estimate forced the sensationalist writers to look for new superlatives, one of the favorite being “Biological Big bang”. Gould argues that the rapid rate of appearance of new forms of life demands another mechanism to explain them, other than natural selection.
Ironically, we’ve come back to the starting point since the days of Darwin. When he proposed his theory, one of the great difficulties was the estimated age of the Earth. The XIX century physicists thought that the Earth had only 100 million years, though Darwin thought that natural selection would require a much longer time to generate life. Evolutionists now affirm that the Earth is much older: around 5 billion years old. With the discovery of the biological Big bang, however, the length of time necessary for life to go from simple to complex shortened to much less that the estimated age of the Earth in the XIX century.
Another serious problem of the fossil record that evolutionists cannot explain is that the majority of plant and animal groups appear abruptly. There are no evidences that there were transitional forms among these groups. Neville George, a known evolutionist, declared: “There is no need to apologize any longer for the poverty of the fossil record. In some ways it has become almost unmanageably rich, and discovery is outpacing integration … The fossil record nevertheless continues to be composed mainly of gaps.” Paleontologist Niles Eldredge thus states the problem: “No wonder paleontologists shied away from evolution for so long. It seems never to happen. Assiduous collecting up cliff faces yields zigzags, minor oscillations, and the very occasional slight accumulation of changeover millions of years, at a rate too slow to really account for all the prodigious change that has occurred in evolutionary history. When we do see the introduction of evolutionary novelty, it usually shows up with a bang, and often with no firm evidence that the organisms did not evolve elsewhere! Evolution cannot forever be going on someplace else. Yet that's how the fossil record has struck many a forlorn paleontologist looking to learn something about evolution.
CONCLUSION
We can see that the so called “evidences” of evolution are not as convincing when analyzed in a different prism. The similarities between living beings can be well explained by the Creationist model, assuming that The Creator utilized similar basic plans. And the fossils, on exact opposition to what the defenders of the evolutionary theory desire, show that never in time there were intermediary forms between distinct groups of living beings. This absence of links between the diverse kinds of living beings is also present in today’s wolrd.
REFERENCES
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BRAND, L. Faith, reason and earth history. Berrien Springs, Andrews University Press, 1997.
ELREDGE, N. Reinventing Darwin. Nova York, Wiley, 1995, p. 95
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