Last time I made the statement about evolution being stuck in the nineteenth century and this did cause some comments about how evolution has changed over the years. However I stand by my original assertion. Yes, there have been minor changes taking in account modern genetics and cell theory. We know much more about how complex cells are and now know the complexity of RNA and DNA but pop the hood on evolution and we have the same engine that was installed over 150 years ago. The basics have not changed natural selection and gradualism, small changes built up over long periods of time.
Now let’s be clear, I have no issues with natural selection. We see that all around us as species unable to adapt to changing environments go extinct. We see this in bacteria as those naturally resistant to antibiotics survive and reproduce while those not resistant die off. The black plague and the Spanish flu pandemic of the early twentieth century show that some humans had a natural resistance to these devastating diseases. But, natural selection can only select what exists. It cannot create and it cannot plan. Every step of the way needs to be beneficial to the organism and provide a survival benefit. Natural selection needs something to select, something that provides the organism a survival benefit.
Today I want to look at what I think is the key to evolution, gradualism. Gradualism just does not fit the observations. I also believe that there is simply not enough time for a gradual change from the first single cell organism to modern humans. But let me get out to the way and let’s see what the late Stephen Jay Gould has to say about gradualism in his book The Structure of Evolutionary Theory. All quotes are from the first edition copyright 2002 and from chapter nine Punctuated Equilibrium and the Validation of Macroevolutionary Theory under the heading Testimonials to Common Knowledge.
Anatomy may fluctuate through time, but the last remnants of a species usually look pretty much like the first representatives… Paleontologists have always recognized the long-term stability of most species; we had become more than a bit ashamed by this strong and literal signal, for the dominant theory or our scientific culture told us to look for the opposite result of gradualism as the primary empirical expression of every biologist’s favorite subject–evolution itself.” p. 749
For example, in 1903 H.F. Cleland … wrote the following: “In a section such as that of the Hamilton formation at Cayaga Lake… if the statement natura non facit saltum* is granted, one should, with some confidence expect to find many – at least some – evidences of evolution. A careful examination of the fossils of all zones, from the lowest to the highest, failed to reveal any evolutional changes, with the possible exception of Ambocoelia praeumbona (a brachiopod). The species are as distinct or as variable in one portion of the section as in another. Species varied in shape, in size and in surface markings, but the changes were not progressive. The conclusion must be that… the evolution of brachiopods, gastropods and pelecypods either does not take place at all or takes place very seldom, and that it makes little difference how much time elapses so long as the conditions of environment remain unchanged(quoted in Brett, Ivany, and Schopf, 1996, p.2).” ( * Nature makes no leaps) p. 750
“Evolutionary theory may be a wonderful intellectual frill, but workaday paleontology, until recently used fossils primarily in the immensely useful activity (in mining, mapping, finding oil, etc.) of dating rocks and determining their stratigraphic sequence. These practical paleontologists dared not be wrong in setting their criteria for designating ages and environments. They had to develop the most precise system that empirical recognition could supply for specifying the age of a stratum; they could not let theory dictate a fancy expectation unsupported by observation. Whom would you hire if you wanted to build a bridge across your local stream – the mason with a hundred spans to his credit, or the abstract geometer who has never left his ivory tower? When in doubt, trust the practitioner.” p. 751
If most fossil species changed gradually during their geological lifetimes, biostratigraphers would have codified “stage of evolution” as the primary criterion for dating by fossils… But in fact biostratigraphers treat species as stable entities throughout their documented ranges–because the vast majority so appear in the empirical record.” p. 751
“We made the following remakes in closing our first paper on the application of our model to biostratigraphy (Eldrege and Gould): (We) wondered why evolutionary paleontologists have continued to seek, for over a century and almost always in vain, the “insensibly graded series” that Darwin told us to find. Biostratigraphers have known for years that morphological stability, particularly in characters that allow us to recognized species-level taxa, is the rule, not the exception. It is time for evolutionary theory to catch up with empirical paleontology, to confront the phenomenon of evolutionary non-change, and to incorporate it into our theory, rather than simply explain it away.” p. 752
“So if stasis could not be explained away as missing information, how could gradualism face this most prominent signal from the fossil record? The most negative of all strategies – a quite unconscious conspiracy of silence – dictated the canonical response of paleontologists to their observation of stasis… Paleontology therefore came to view stasis as just another failure to document evolution. Stasis existed in overwhelming abundance, as every paleontologist always knew. But this primary signal of the fossil record, defined as an absence of data for evolution, only highlighted our frustration – and certainly did not represent anything worth publishing. Paleontology therefore fell into a literally absurd vicious cycle. No one ventured to document or quantify – indeed, hardly anyone even bothered to mention or publish at all – the most common pattern in the fossil record: the stasis of most morphospecies throughout their geological duration.” pp. 759-760
The simple fact is that the fossil record does not support gradualism. Even so called intermediary species are just fossils that someone has decided must be transitional because they have similar features or fall in the right order in the stratum. What is not seen is actual transitional features such as and arm gradually changing into a wing or a fin. For the longest it was thought that the Archaeopteryx was the link between dinosaurs and birds. It fell in the fossil record before modern birds and had many of the same traits as dinosaurs. Then over the past few decades modern bird fossils have been found in China that predate the Archaeopteryx. Another missing link bits the dust. Now it is believed that the Archaeopteryx is a feathered dinosaur which explains why it has so many features in common with theropod dinosaurs.
For over 150 years evolutionists have been telling everyone just give us some more time and the transitional fossils will appear. We still are waiting. At what point do we say enough is enough and change the theory to fit the observations? Biology seems to be the only field that steadfastly refuses to adjust the theory to fit the facts. Just recently there was an article in the Houston Chronicle dated November 29, 2012 about scientists finding an enormous black hole in the in a small disk shaped galaxy smaller than the Milky Way galaxy. This galaxy is a rather small galaxy and according to current theory should not have such a large black hole. So what are the cosmologists and astronomers going to do? If they follow the biologists they wound just ignore the observation and say that eventually we will find something to fit or they can change the theory. To their credit they are looking at changing the theory to fit the observations. How novel.
Evolution may eventually be changed to fit the facts and could be actually proved to be correct. But based on its track record so far not until the theory is changed to fit the facts. Until then we have a theory and we have the observations unfortunately they do not mesh.
As an aside, it has bothered me that such a respected scientist and author as Stephen Jay Gould would be treated as though he had somehow betrayed the cause because he dared question not evolution but gradualism. If evolution is beyond questioning by scientist then who can question it and how will it evolve?
Have a blessed day,
PS I apologize for the delay between postings on this subject but I wanted to do justice to the subject. This means a lot of side reading such as Gould’s book and for the most part I just do not like to use Wikipedia as my source. At the moment this looks like it will be a nine part series. So bear with me and as always I appreciate your comments, just keep them civil. I have always believed that we need to be open to opposing viewpoints, how else can we learn and strengthen our own arguments.