Those who have followed this blog recently might know of my interest in the fossil history of the Earth. It should not be surprising, then, that I also have a deep interest in Biology as a subject. As a card-carrying science geek for most of my life, my particular area of interest was always Biology. Of all the geeks in AP Biology, I was geekiest among them. My AP Biology teacher once told my mother that if she had a daughter, she would want her to marry me. This should tell you a thing or two about the impression I made.
Anyway, just like any student of the time, we were taught about Darwin and Natural Selection. Also known as “survival of the fittest”, the concept of Natural Selection does a lot to explain the behavior of species in real life. It is especially good at explaining how species adapt to a particular niche, and how certain traits are favored over time if they lead to some kind of survival advantage. However, once a species is adapted to its niche, we no longer see changes. There have been species in the oceans which are virtually unchanged for the past 500 million years, even if improvements could still be made (the Horseshoe crab, for instance). Indeed, these unchanged species are not perfect, but they are perfect for their particular niche. If Natural Selection were constantly driving new species (speciation), then these unchanging species are a big problem for it being the main driver for speciation events.
Do not think that I am calling Natural Selection invalid here. One must only look towards species isolated on islands to see all kinds of strange happenings (flightless birds, for example) as a product of Natural Selection. However, the one thing Darwin’s theory of Natural Selection was supposed to be revolutionary for was as an explanation for speciation events. I think back to my time in AP Biology for this, as the teacher had us do an experiment that was supposed to show how this speciation should come about through Natural Selection. All I remember about the experiment is that it involved trading slips of paper to “select” for favorable traits. In their telling (think to the example of the species isolated on an island), we would see such dramatic differences between the populations over time that eventually we would end up with a totally new species. There is only one problem…this has never been shown to happen…not once, not ever. I was the sole confused student who knew something was wrong. The smartest kid in the class should be the one who “gets it”, but in this case, I was the sole kid who didn’t get it. Immediately, I could see that this experiment did not work. A dog reproducing with another dog will always lead to an offspring of the same species (a dog). Even many generations down the line of isolated populations (Great Dane and Shitszu, for example), we are still left with two dogs. Two dramatically different dogs, perhaps…but still dogs nonetheless. If the two dogs are still sexually compatible, their offspring will always be a dog. In this way (and more), Natural Selection does not explain speciation. In this write-up, I hope to support a different explanation for speciation…one given by Immanuel Velikovsky and the catastrophists.
Natural Selection can indeed cause such dramatic changes that eventually two populations are no longer sexually compatible, but this would not lead to the creation of a NEW species…just two incompatible dogs. The history of life on earth, seen through fossil records, shows that there have been many true speciation events. Brand new forms of life springing forth. None is more well-known than the Cambrian Explosion. The Cambrian Explosion was a dramatic diversification in the forms and complexity of life which happened not long after atmospheric oxygen levels rose to near present-day levels. For billions of years prior to this, there were only simple eukaryotic and prokaryotic-celled life forms. Then, about 550 million years ago, there was a sudden explosion in complex life forms. All present-day forms of life are derived from life forms which came about as part of the Cambrian Explosion. The most interesting thing about the Cambrian Explosion is that its cause is not well understood. Just like Darwin’s Natural Selection being an inadequate explanation for speciation events, we do not have an adequate explanation for the Cambrian Explosion.
So, if Natural Selection does not explain speciation events, then what does? The main driver of the Cambrian Explosion is believed to be increased genetic mutation. That is not to say that we understand WHY this increase in the mutation rate occurred, but it is believed to be the key to the Cambrian Explosion. Indeed, genetic mutations are seen as critical to speciation events. The rate of genetic mutation is typically very slow, and random genetic mutations are very rare. Even rarer is an advantageous random mutation, which is nearly unheard of in the present-day. If a birth results in a mutated offspring, this single offspring is incompatible with all other members of its species. It cannot procreate. Even if this mutated offspring somehow had an advantageous mutation (which is even rarer than any old mutation), then it would still not be able to develop into its own species by virtue of it being a one-of-a-kind. This is the problem, and why random mutations were not seen as the main driver of speciation events. The regular rate of genetic mutation does not lead to speciation events, and Natural Selection does not explain speciation events. What are we left with to ponder?
We must remember that mutations ARE indeed key to speciation events, even if they were somewhat disregarded by scientists due to the regular, random rate of mutation being inadequate (too slow) to explain speciation. A key realization is that random mutations are only inadequate to explain speciation events throughout the history of life on Earth if the rate of random mutation is always constant. What if the mutation rate is NOT constant? Mutations are what could theoretically cause a new species to come about. What is then the idea that we have to consider? Instances of SUDDEN and DRAMATIC increase in the rate of mutation. How could this come about? Any number of ways, I suppose. This is where it gets interesting, and where Velikovsky comes in.
Immanuel Velikovsky was a Russian scholar who lived from 1895 to 1979 who believed that the history of Earth was largely defined by a series of great catastrophes. In the world of fossil study, there is a great disagreement between two concepts: uniformitarianism and catastrophism. Uniformitarianism, also known as gradualism, is the idea that things occur gradually and constantly. As in above where I reminded you that scientists have assumed that the rate of random mutation has always been constant. Under uniformitarianism, every process that is happening right now on Earth has always been happening, and will continue to happen at this uniform rate over geological time (hundreds of millions of years). Catastrophism, on the other hand, is just as it sounds. Changes come about catastrophically and suddenly, with periods of inactivity between. Natural Selection was seen as a key uniformitarian concept to explain speciation. Under this idea, the survival of the fittest over time resulted in new species. We have explained that this is faulty logic. As mentioned, it does not actually hold with what we see in reality. Natural Selection has never once been shown to be the cause of a new species, and remember…under uniformity whatever is happening now has always been happening. If Natural Selection is not creating new species now, then it has never been creating new species. As for catastrophism, one of the key observations noted in Velikovsky’s book “Earth in Upheaval” is that after bombings in London in WW2, unknown plants grew in the bomb craters that had never before been witnessed in London. This may have been a stray observation, but it is a critical one. Under catastrophism, speciation would result from any number of different catastrophic events, but on a planetary scale. These catastrophic events would have caused a dramatic increase in radiation, which would have then dramatically increased the rate of mutation.
You might ask HOW an increased mutation rate would lead to speciation events, and for this I can provide a very clear example. We had previously discussed the rare example of a single offspring with an advantageous mutation not being able to propagate with a compatible partner because it is one-of-a-kind. If instead we saw a sudden and dramatic catastrophic event which raised the mutation rate through increased radiation, then we would see ALL offspring from ALL populations suddenly have similar sets of mutations. Since these mutated offspring are all born at once, then it would just take one compatible pair to reproduce, and bam…a new species would be born. It would be a speciation event. Simple as that. This is a much more compelling explanation for speciation throughout the history of life on Earth. In the case of the Cambrian Explosion, we can envision an increase in radiation coinciding with higher oxygen levels to bring about a dramatic explosion of new, complex life on Earth.
The question becomes what kind of sudden, catastrophic events could suddenly raise the radiation level and mutation rate? Well, I suppose there are all kinds of different examples to pick from there. Velikovsky proposes that Earth has had close calls with other planets in its history (even very recently). This would certainly raise the radiation levels to suddenly boost the rates of mutation. However, there are many other possibilities. A gamma ray burst, for example, would do the trick. Earth’s position in the Milky Way galaxy could also make it pass through an area of heightened radiation. Velikovsky’s idea about close encounters with other planets is certainly possible, but I do not feel that we need to limit the thinking to only this. We could also think of events like a magnetic pole shift as being a possible mechanism for raising radiation levels. When the magnetic poles are firmly in position, much of the life on Earth is protected from intense radiation levels. If the poles were to shift, this could cause high levels of radiation, and speciation events for animal life on Earth. There are innumerable sources of high radiation throughout the universe, and when we are dealing with billions of years, we can imagine there may have been many different explanations for bursts of radiation over this time.
In the end, we are left with Natural Selection as simply a mechanism for the periods between the bursts of radiation. Organisms do select for favorable traits over time to adapt themselves to each niche. The main driver for this is Natural Selection. With that said, Natural Selection has nothing whatsoever to do with speciation events. To explain the speciation events, we must look to the catastrophists, like Velikovksy. Rates of mutation cannot be viewed as constant across billions of years. The sudden periods of heightened radiation would lead to a dramatically higher mutation rate, and therefore lead to new species. The fossil record supports this explanation for speciation, with sudden bursts and completely new and different types of species appearing following each catastrophic event.
PS-I will close with an image of my favorite fossil. All of the fossils in my collection were found by myself, not bought. This is of Silurian age, and is an orthocone (straight-shelled) cephalopod sitting on tabulate coral. Both species now long extinct.