On
the website, evolutionfaq.com, there's an article titled, Five
Proofs of Evolution. I can see the article is geared toward a
lay audience and is certainly not very technical so I won't try to
pretend that this is the best evidence evolutionists have. On the
other hand, the author calls these five examples “proof” of the
theory. What's more, there is a lot of supposed evidence for
evolution out there and this site picked these five to make the
argument for the theory so they must think they're somewhat
compelling. So even if they're not what I would consider great
evidence for the theory, this website presents them as though they
are. Let's take a look at list and see.
1)
The universal genetic code. All
cells on Earth, from our white blood cells, to simple bacteria, to
cells in the leaves of trees, are capable of reading any piece of DNA
from any life form on Earth. This is very strong evidence for a
common ancestor from which all life descended.
Universal
DNA is not a prediction of evolution. Certainly if all life
descended from a single common ancestor with DNA, then all living
organisms should also have DNA but there's nothing about evolutionary
theory that requires abiogenesis to have only occurred once. Another
lineage could exist that did not have DNA. Would that then prove
evolution false? Hardly. Therefore, whether DNA is universal or
not, the theory of evolution would chug along either way.
It
makes perfect sense, on the other hand, to believe that universal DNA
is the product of design. If God originally intended people and
animals to eat only plants, for example, it wouldn't be possible if
the various life forms were completely alien to each other.
2.
The fossil record.
The
fossil record shows that the simplest fossils will be found in the
oldest rocks, and it can also show a smooth and gradual transition
from one form of life to another.
This
is a misleading characterization of the fossil record. First, many
of the creatures appearing near the bottom of the illustration
provided with the article, are organisms that are still alive today –
sponges, protozoans, and protists. Over the last 500 million alleged
years, sponges have evolved into what? Sponges?
The
fossil record shows something completely different than simple to
complex progression from bottom to top. If you looked at a cross
section of the earth, you would see marine animals at the lowest
layers with plants, birds, and mammals at the top. That very closely
resembles the order in the article's tree-of-life chart. I maintain
that the appearance in the fossil record more closely depicts where
the creatures lived rather than when they lived.
3.
Genetic commonalities.
Human
beings have approximately 96% of genes in common with chimpanzees,
about 90% of genes in common with cats, 80% with cows, 75% with mice,
and so on. This does not prove that we evolved from chimpanzees or
cats, though, only that we shared a common ancestor in the past.
The
similarity between human and chimp DNA has been vastly exaggerated,
to the point of lying. I
wrote about this just a few months ago. Most telling is that
chimp DNA is 8% longer than human DNA. Therefore, if the two were
identical in every other respect, they could only be 92% similar at
most. But human/chimp DNA are not identical except for their length.
If you do a letter by letter comparison of human/chimp DNA,
estimates of their similarity range between 70-81%. So if similar
DNA “proves” we shared a common ancestor with chimps, then
dissimilar DNA should be evidence against having a common ancestor.
Regardless
of all this though, I reject the premise that similar DNA must be the
result of common descent. DNA has been compared to blueprints; they
are the instructions that build living things. The more similar 2
creatures are, the more similar their DNA should be. Even according
to creation theory, human DNA would be more like a chimp's than a
bird's. Consider this, if I drew 2 lines, one 9 inches and one 10
inches, the lines are 90% similar – but they are similar because I
drew them that way, not because they have a common ancestor!
4.
Common traits in embryos. Humans,
dogs, snakes, fish, monkeys, eels (and many more life forms) are all
considered "chordates" because we belong to the phylum
Chordata.
One of the features of this phylum is that, as embryos, all these
life forms have gill slits, tails, and specific anatomical structures
involving the spine. For humans (and other non-fish) the gill slits
reform into the bones of the ear and jaw at a later stage in
development. But, initially, all chordate embryos strongly resemble
each other.
Ernst
Haeckel was a professor of biology about the time of Darwin. He
published several papers and books where he presented a series of
drawings comparing the embryos of different animals. He advanced a
theory called embryonic recapitulation which basically says
that, as embryos develop in the womb, they progress through stages
similar to our supposed evolutionary history.
There
was a controversy surrounding Haeckel with claims that he
intentionally altered the drawings to make the embryos more similar.
Modern photos we've taken of embryos at the same stages as Haeckel's
drawings do not show the same similarity Haeckel saw.
Human
embryos do not have gill slits. At a certain stage of development,
human embryos have folds in the skin of their necks that bear a
superficial resemblance to gill slits. As they develop, though, the
folds become glands and parts of the ears. They have nothing to do
with the respiratory system as fish gills do.
When an antibiotic is applied, the initial innoculation [sic] will kill most bacteria, leaving behind only those few cells which happen to have the mutations necessary to resist the antibiotics. In subsequent generations, the resistant bacteria reproduce, forming a new colony where every member is resistant to the antibiotic. This is natural selection in action. The antibiotic is "selecting" for organisms which are resistant, and killing any that are not.
The
author here has precisely described natural selection. I've said
many times that natural
selection is the opposite of evolution. Some bacteria in the
colony already have the immunity to antibiotics and the ones that
don't are removed. It's survival of the fittest. Pointing to an
example of unfit creatures being removed from a population doesn't
demonstrate the kind of evolution that would add feathers to
dinosaurs or legs to fish. Evolutionists routinely conflate natural
selection with evolution as though they are the same thing. They're
not. Evolutionists want to use examples of things we do observe
(natural selection) as evidence for something we don't observe
(evolution).
In conclusion, these supposed "proofs" of evolution are hardly persuasive. Not even in the least. Is this the best they have. Surely not. What it does demonstrate is how people's belief in evolution is less about the evidence and more about their willingness to believe in evolution.
1) Finding the murderer's fingerprints, at the crime scene, in the victim's blood, is not a prediction of "suspect X murdered victim Y," but if you find it, it looks very bad for suspect X. Certainly the claim "I could have murdered him without leaving fingerprints" is a weak defense indeed. By the same token, it is not required by evolutionary theory that, e.g. feathered dinosaur fossils actually exist, but the fact that they do remains evidence for a link between non-bird dinosaurs and birds. And the near-identical genetic codes used in all known life remain evidence likewise.
ReplyDeleteIt has long been pointed out that if abiogenesis were still occurring, it wouldn't get very far: the already-existing microbes would use the spontaneously forming proteins and nucleic acids as food sources before they could start a new lineage of life on their own. So once life gets a foothold on Earth, new starts for unrelated evolutionary trees are likely to be aborted. Even if multiple simultaneous abiogenesis events occurred, a slight superiority in one version might drive all other versions of life extinct, so that, again, you'd have only one surviving evolutionary tree. Multiple abiogenesis events are not that likely to leave multiple separate evolutionary trees.
Yes, one might expect a common genetic code from a common designer. Or one might not. After all, the disparate arrangements of the retina in vertebrates and cephalopods, or the different way that the vertebrate forelimb is altered to make a wing in pterosaurs, birds, and bats, might suggest that the Designer would prefer a variety of genetic codes. Note that identical codes aren't needed to code for identical proteins: since in the present code, each amino acid is coded for by two to six different codons, even with the present code you could have identical organisms coded for by very different genomes -- and since presumably different genetic codes are possible, you could have very different genetic codes (e.g. one in which UUU coded for glycine rather than phenylalanine) still yielding identical proteins and organisms. We don't need to share a genetic code with potatoes to be able to eat them.
One more point: the genetic code is not quite universal; some groups of life have slightly different codes. It's not easy to mutate the genetic code itself (if a mutation caused UUU to start coding for phenylalanine, then hundreds of sites in thousands of proteins would be suddenly changed; at least one of those changes would likely prove highly deleterious), but there are theoretical ways it could happen on rare occasions. The present state: slight variations on the code, arranged in a nested hierarchy ("tree pattern") seems more in line with what we would expect of gradual descent with opportunistic modification than from intelligent design.
2) You might add that cyanobacteria have been around, judging from the fossil record, for over three billion years, and are still recognizably cyanobacteria (photosynthesizing bacteria, sometimes misleadingly called "blue-green algae"). And monkeys are still around, even after some of them evolved into apes and some apes evolved into humans. Evolution is a tree, not a ladder, and sometimes one branch of the tree remains morphologically primitive even as another becomes more and more derived. It still remains the case that we find single-celled prokaryotes (cells without nuclei and organelles) before single-celled eukaryotes (cells with nuclei and organelles -- though here the record is biased because the oldest eukaryotes are cells with hard, fossilizable silica shells), and single-celled organisms before sponges and other multicellular life.
ReplyDeleteIf fossil layers represented where an organism lived rather than when, we'd expect modern species of bottom-dwelling life to be found in the lowest levels, rather than seeing, e.g. trilobites rather than modern deep-sea fish. We'd expect whales and ichthyosaurs to be buried together rather than in separate strata and formations, or elephants and sauropods to be more closely associated with one another. Or, as has been pointed out, if young-earth creationism were true, Tiktaalik was just as likely to be a dolphin as a lobe-finned fish. The modern sea-bottom isn't wall-to-wall stromatolites (bacterial colonies) without any vertebrates or arthropods, so why should the oldest layers of fossil-bearing rocks be?
3) There are different ways of counting genetic similarities; if, e.g. the eight percent greater length of the chimp genome consists of multiple copies of elements that exist in only one copy in humans, you can count each copy as a single difference (gene duplication is a known type of mutation) rather than as one difference for each extra nucleotide. And this is an honest way of counting if you're interested in how hard it would be to derive the two genomes from a common ancestor. Note that no matter how you count, human and chimp genomes are more similar than horse and zebra genomes (and less different in chromosome count!), or lion and house cat genomes. If you're minded to derive the entire genus Equus (never mind the entire, mostly extinct family Equidae) from a single pair of ur-equines aboard Noah's Ark, you can't find the differences between humans and other great apes to be prohibitively huge.
ReplyDeleteAgain, given the degeneracy of the genetic code (the way two to six different codons can correspond to each amino acid), you don't need highly similar genomes to produce highly similar organisms. There's certainly no reason to expect, e.g. shared pseudogenes (e.g. identically-disabled GULO pseudogenes in humans and other old-world simiiformes) shared between unrelated "kinds." On the principle of special creation, there's no obvious reason to expect that, e.g. all birds should have a right but not a left aortic arch, while the opposite conditions prevails among mammals (the last common ancestor would presumably have both -- the loss of one aortic arch is an adaption to warm-bloodedness). And so forth and on: the distribution of similar and dissimilar traits is better explained by common descent with modification than by common design.
4) Not that the original article mentioned Haeckel, but anatomical illustration has priorities other than photo-realism: compare, e.g. the neat, distinct organs in your standard human anatomy diagram with the squashed-together, compressed cluster of organs in a real body -- or the identical, "standard" organs thus depicted versus the variation seen among the organs of real individuals. The photos that accompany Hackel's drawings aren't necessarily more "typical" of what these embryos look like (different embryos of the same organism will look different and take different positions). The point is that the structures Haeckel identified do exist, whether you call them "gill slits" or the more proper "pharyngeal arches." The point is that the same structures are present in different vertebrate species, whether they develop into the jaws and branchial arches that support the gills of fish or into the jaws and inner ears of mammals (it is generally supposed that vertebrate jaws originated from the first branchial arch in some early fish, while there are a series of synapsid fossils showing how two bones on each side of the lower jaw shrunk and detached and became two bones in the inner ear). There does not seem any "common design" reason why species designed to be disparate and unrelated should derive their structures from such common precursors, but it does make sense if they are products of diverging descent from a common ancestor, forced to make do with modifications of ancestral embryology.
ReplyDeleteThere are various other examples: one of the most notable is the hind limb buds and teeth that are grown and then resorbed by embryonic baleen whales (who have, of course, neither hind limbs nor teeth after birth). In whale embryos, also, the nostrils form near the tip of the snout (the typical mammalian position) before different growth rates in different parts of the skull cause them to migrate to above and behind the eyes to form the blowhole). Embryology is replete with features explicable in terms of common descent but rather odd in terms of common design (since we should expect special creation to produce common design only where common function or common adult structure exists).
5) It is not necessarily the case that some bacteria have an allele (variant of a gene) for antibiotic resistance. One can start with a monoclonal colony (started from a single bacterium and genetically identical to one another), let it grow, expose it to UV light to raise the mutation rate, and find that any of several possible mutations conferring antibiotic resistance have occurred. Note that the UV light is simply a time-saving measure; let the colony survive long enough and a range of mutations will arise naturally.
ReplyDeleteNor is it true, entirely, that natural selection merely prunes away less fit variants and builds nothing new. In a sexually-reproducing species (bacteria don't sexually reproduce, but they do occasionally exchange genes with one another -- or bacterial genes opt for free agency and join a new team, depending on how one looks at it), two rare variants that each confer some advantage may grow common enough that they have an opportunity to join up in the same individuals. But the point is that the mechanisms of evolution -- mutation and natural selection -- are readily observable and ubiquitous. It is an advantage for any theory that it depends on things that actually happen, and a disadvantage if it depends on phenomena that are known only from legend and unattributed anecdote.
Steven J,
ReplyDeleteOnce again, you have left more comments than I have time or space to answer. I may use some of them as material for future posts so stay tuned. Regardless, I'll make a few points now.
Theories are only ever attempts to explain the evidence and you and I offer two different explanations of the same evidence. A universal genetic code, for example, could be the result of common descent or it could be the result of a common designer. My point in raising the fact that it's not a prediction of evolution is to dispel the idea that using evolution to explain universal DNA is not proof of evolution as was claimed by evolutionfaq.com. Evolution could be true with or without a universal genetic code so citing it couldn't possibly be proof of evolution. It's a common ploy of many evolutionists to use their theory to explain some phenomenon – then cite that phenomenon as evidence for their theory. It's circular reasoning. I've used this analogy before:
Imagined that you and I are walking and we find a black rock with purple stripes. I suggest that aliens painted the stripes on the rock. What evidence do I have for this? Well, there is the rock and there are the stripes so that's certainly evidence for my theory!
As far as progression in the fossil record from simple to complex, I am genuinely curious how evolutionists define “simple.” How do we quantify that a sponge is more “simple” than a mushroom or that a snake is more “complex” than a fish? I don't see any such thing in the geological column; rather, I see complex life forms from bottom to top. Actually, I see marine animals from bottom to top. It's more like bottom-dwelling marine animals, swimming marine animals, marine animals with amphibians, marine animals with reptiles, and marine animals with birds & mammals.
By the way, I wouldn't expect to see modern species in the fossil record. I would expect to see species as they existed at the time of the flood.
That's about all I have time for now. Thanks for your comments. God bless!!
RKBentley
This is utter nonsense. If it is true, please publish your paper in www.nature.com and win the Nobel prize for disproving evolution.
ReplyDeleteRajiv,
ReplyDeleteThank you for your comments. It's typical of people who disagree with me to make snide remarks without even attempting to point out any factual errors. “This is utter nonsense,” isn't a rebuttal of any sort so there's nothing to which I can respond.
I invite you to keep visiting and commenting. God bless!!
RKBentley