I asked a professor why evolution is a fact and he listed off several evidences. Was he correct, is evolution a fact? The answer ultimately depends on you because there is no objective criteria for facthood. So there is bound to be disagreement, but let’s at least agree on our disagreement.
When I asked the professor why evolution is a fact he focused specifically on the evolution of humans and offered seven evidences: biogeographical data, fossils, genetic similarities between species in protein coding DNA, genetic similarities between species in non coding regions, genetic similarities between species involving transposons and retro viruses, and the fusion of human chromosome #2.
But there are two problems here. First these evidences are decidedly mixed, and second they are also selective. If these evidences make evolution a fact, then a great many things most people consider unlikely are, in fact, facts.
The evidence for evolution is mixed
In mandating evolution, the professor cited genetic similarities between the human and chimpanzee. There are indeed great similarities. In fact these two genomes are so similar it suggests there are other reasons for the human and chimp differences. Furthermore the DNA differences we do find don’t fit the expected evolutionary pattern.
It turns out that the differences between the human and chimp DNA instructions are not sprinkled, more or less at random, throughout our genome. Rather, these differences are found in clusters. Even more interesting, at these locations the chimp’s genome is quite similar to other primates—it is the human that differs from the rest, not the chimp.
Evolutionists refer to these clusters as
human accelerated regions (HARs) because they believe the human genome evolved from a human-chimp common ancestor. Often these HARs are found in DNA segments that do not code for genes (the majority of the genome does not code for genes). These HARs cause several problems for evolution. For instance, we must believe that evolution caused rapid changes to occur right where needed to improve function and eventually create a human. As one evolutionist
wrote:
The way to evolve a human from a chimp-human ancestor is not to speed the ticking of the molecular clock as a whole. Rather the secret is to have rapid change occur in sites where those changes make an important difference in an organism’s functioning. HAR1 is certainly such a place. So, too, is the FOXP2 gene, which contains another of the fast-changing sequences I identified and is known to be involved in speech.
Furthermore, some HARs are found in DNA segments that do code for genes, and here we find another story of contradictions.
Of course the evolutionary expectation was that humans evolved from the chimp-human ancestor via natural selection acting on mutations, to improve the genes. That is, mutations happen to occur in the genes and occasionally a mutation was helpful or at least not harmful (neutral). In those cases it may well persist and eventually become established in the population.
But
findings published earlier this year reveal nothing of the kind. Assuming evolution is true, the HARs that were found in protein coding genes showed evidence not of mutations that had been selected because they were genetically helpful, but rather the exact opposite. The genetic changes showed evidence that they were, in fact, at least slightly deleterious. They had become established in the population not because they were helpful (or not harmful), but in spite of being deleterious. As the evolutionists concluded, the results led to:
the provocative hypothesis that many of the genetic changes leading to human-specific characters may have been prompted by fixation of deleterious mutations.
Once again the results make little sense under evolution.
Another problem with this genomic comparison evidence is that amongst the primates it often does not correlate well with morphological differences, as evolution would predict. For instance the orangutan looks and acts more like humans than do chimps. As one evolutionist admitted, if it weren’t for DNA, it would be the orangutan rather than the chimp pictured next to the human in the evolutionary tree. Contra the DNA evidence, only a handful of visible characters make it look like humans are most similar to chimps, whereas many more characters point to orangutans being more similar to humans than chimps. As one researcher put it:
There remains, however, a paradoxical problem lurking within the wealth of DNA data: our morphology and physiology have very little, if anything, uniquely in common with chimpanzees to corroborate a unique common ancestor. Most of the characters we do share with chimpanzees also occur in other primates, and in sexual biology and reproduction we could hardly be more different. It would be an understatement to think of this as an evolutionary puzzle.
Yet once again we find conflicting characters when trying to align the species to an evolutionary tree. Even presupposing that evolution is true, we are left with an array of contradictory data. Here is how one evolutionist summed it up:
revisiting the red ape is a useful reminder that not everything to do with morphology can be attributed to the closeness of a genetic relationship. We can evolve likenesses even to our more distant cousins if both sets of ancestors faced similar problems.
You can read more about this
here.
The professor also mentioned the fusion of human chromosome #2. It would have been a problem for evolution if apes and humans had different number of chromosomes without any fusion events. We do have fewer chromosomes, but a fusion event was discovered. So evolution escaped what presumably would have been a problem. But the fusion event itself has nothing to do with evolution. We infer that such an event occurred, but there is no need for evolution to be true for the event to occur. So the evidence is interesting, and evolution escapes a problem, but there is nothing powerful here in support of the theory. Yet the professor described this evidence as demonstrating an evolutionary relationship: You can read more about the human chromosome #2
here,
here and
here.
A similarity does not demonstrate an evolutionary relationship. This is a misrepresentation of the scientific evidence. The fact that we share the same number of chromosomes with apes, or that we have a similar body plan, or that species share the same genetic code, or that different species of fish share similar gills, and so forth, does not demonstrate evolution.
There is of course much more that could be said about the scientific evidence. And it is not all bad for evolution. There are supporting evidences for evolution, and it has its successful predictions. But there are substantial scientific problems within the empirical evidence. While the evidence may be mixed, there is no question that evolution does not qualify as a scientific fact in the same sense that gravity or the round shape of the earth are facts. There is, however, an entirely different problem with the evidence that evolutionists set forth.
The evidence for evolution is selective
The evidence provided by the professor is selective. Yes, there is some supporting evidences within the professor’s categories, but he omitted entire categories that present substantial problems for evolution. This is a long story, but one rather obvious problematic category is that of mechanism. How is it that a living cell arose from inorganic chemicals? How did that population lead to multicellularity? How did fish arise, and then amphibians and birds and mammals? How did everything from the cardiovascular system to the brain arise?
There are few detailed answers to such questions. What we have mainly is speculation based on the assumption that evolution must be true. Evolution cannot even explain how proteins initially arose. The empirical evidence, rather, points to how astronomically unlikely their evolution would be. You can read more about this
here,
here,
here,
here,
here and
here.
Seeking agreement
In spite of these well known evidential issues the professor was insistent that evolution is a fact beyond all reasonable doubt. It is, he explained, a fact because what we observe shows it to be a fact. The scientific evidences say evolution happens and has happened, and we are relatives of many other living species, if not of all, in the planet. Of course these high claims are typical. Evolutionists say their theory is compelling and that it would be perverse and irrational to doubt it.
Obviously evolutionists have very unusual logic for determining what qualifies as a scientific fact. I’m not expecting them to change their minds about this, but perhaps we can understand that very different reasonings are at work. Perhaps we can agree about our disagreement.