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Richard Dawkins, the key proponent of the selfish gene theory of evolution, revolutionized the way evolution was viewed by proposing that organisms are simply the ‘vehicles’ for genes, and that genes preserve their own existence by promoting qualities and behaviours that increase the organisms chance of survival into the next generation. Dawkins view of evolutionary theory makes it a lot easier to understand ideas such as kin selection and altruistic behaviour, however it does encounter some large theoretical problems such as those of incipient stages. The main objection to Dawkins theory comes in the form of Stephen Jay Gould who is one of the key proponents of the rival to the selfish gene theory; the punctuated equilibrium theory of evolution. This is just one of many available alternatives but is definitely the one that has attained the most attention. Other alternatives to Dawkins view are those of gaia theory, game theory, group selection and individual selection but all have their difficulties.

Since the discovery of DNA in 1953, genes codified in DNA molecules have been viewed as the persistent entities that are passed down through the generations of an organism. These genes are the causal agents behind the phenotype and as such variations of the phenotype can only be relevant to natural selection if they are firmly attached to a genetic variation. Given this, Dawkins theory, is based upon a few simple facts concerning inheritance and development.

The first of these facts, as previously stated, is that genes are the hereditary information found within DNA molecules. These genes do two important things for the organism; they replicate themselves, and through RNA and protein synthesis they exert phenotypic effects. Secondly, in a biological system, genes are the only replicators and as such, phenotypic variations can only have long term effects on an organism or species if they are produced by genetic differences. Based on this it follows that only genetic mutations are transmitted through generations. Lastly, genes are the only biological parts of an organism that are passed through the generations, and as such, are the only part that exist for an evolutionary long period of time and exist in many copies. Dawkins uses an analogy of a computer programmer. The genes are the computer programmer and they must anticipate every possible eventuality, they must predict the future. All they can do is setup beforehand and hope that they make the write decisions otherwise their organism will more than likely not make it to the next generation (and subsequently they don’t make it to the next generation).

Dawkins theory also made it much easier to interpret phenomena such as kin selection and eusocialty (altruistic behavior). By incorporating simple mathematics into the theory he establishes how such phenomena may work. “At some unconscious level, something functionally equivalent to the mathematical calculations is going on.”

He uses an example of the ethologist Niko Tinbergen where he uses a fish tank with two male sticklebacks to test their behavior. Each stickleback had built a nest at opposing ends of the tank and each defended the territory around their own nest. Tinbergen then place the two males in two separate glass test tubes and place the tubes side by side and watched as they tried to engage each other in battle. He then moved the two test tubes within male A’s territory and watched as male A assumed an attacking posture and male B retreated, but upon moving the two test tubes to male B’s territory the tables were turned and male A was on the back foot attempting to retreat while male B assumed the attack position. This is one of many scenarios that can be envisaged in the real world and is based upon a concept referred to as an evolutionary stable strategy.

Gould as previously stated is the self-proclaimed messiah of the opposing view, he prefers to view evolution as occurring at higher biological forms such as at the level of the species. But Gould is not the only aggressor in this battle, on the contrary, there are many, but all seem to be clinging to old theories or allowing personal beliefs such as religion to dictate their arguments.

Professor Herbert Gintis, who is an economics professor at the University of Massachusetts believes Dawkins gene-centred view of evolution is fatally flawed for one key reason; the heart of evolution is mutation and selection, not replication as is hypothesized by Dawkins. But Dawkins never claimed that replication was the sole force behind evolution, in fact, he has been quoted many times agreeing with the idea that natural selection still plays a role in evolution. Mutation on the other hand is also supported by Dawkins view, as long as it is occurring at the level of the gene. He talks of point mutation where, for lack of a better analogy, a single letter in a book is misprinted.

This translates to a chromosome being programmed the wrong way, much like a spelling error. Another form of mutation that Dawkins talks about is that of inversion, where a piece of chromosome detaches itself at both ends, does a 180 degree turn and reattaches itself. Both of these types of mutation, although rare, are of great evolutionary importance and can have long term effects on an organism as such genetic mutations can tend to be favoured by natural selection.

But there are other problems encountered by Dawkins selfish gene theory of evolution, the biggest of these is that of incipient stages. If evolution is a gradual process over millions of years rather than a sudden mechanism followed by periods of complete stasis as is proposed by punctuated equilibrium it begs some fairly large questions; “we can readily understand how complex and fully developed structures work and owe their maintenance and preservation to natural selection – a wing, an eye, the resemblance of a bittern to a branch or of an insect to a stick or dead leaf. But how do you get from nothing to such an elaborate something if evolution must proceed through a long sequence of intermediate stages, each favored by natural selection? You can’t fly with 2% of a wing or gain much protection from an iota’s similarity with a potentially concealing piece of vegetation. How, in other words, can natural selection explain these incipient stages of structures that can only be used (as we now observe them) in much more elaborate form?”

But the questions raised by Gould’s quote make assumptions that the underdeveloped eye or wing is being used for seeing or flying. There is nothing to suggest that an underdeveloped eye or wing would (or even could) be used until it was completely developed.

Gould’s theory on the other hand, although renowned for complicated and elaborate exceptions does have evidence to support it, however the conceptual difficulties associated with it take away a lot of its force. The three main themes of his exceptions are; offering exceptions to the account of evolution as gradual cumulative change (evolution as progress), pointing to the importance of historical contingency (thus leaving room for catastrophic changes like that of meteor impact on the earth) and establishing the importance of non-adaptive side consequences of variation (biological structures that constrain function even though they were not specifically selected for).

Although one encounters severe terminological vagueness and equivocation throughout his theory there is evidence to support it in the fossil record. This evidence, according to critics, also tends to deny Dawkins theory of gradual evolution over millions of years as if evolution occurs in jumps and jerks then the unit of selection cannot be the gene; selection must occur at a higher level.

“There are lots of sediments from over fifty localities around the world which have good sections which have yielded fossils and when you get that many samples of an interval of just … a few tens of millions of years or so it means that the record is reasonably complete. So we are quite confident that the pattern we’re seeing is not an artificial one, not caused by lack of the fossil record. The rocks are there, plenty of rocks, perfectly good rocks, laid down in the appropriate environment. So the fossils we see probably record the story that happened.”

But just because Dawkins theory makes the assumption that evolution is a gradual process does not mean that the unit of selection is not the gene, Dawkins may be wrong in his theory in some respects but that does not take away the key element of the selfish gene theory.

Of the other alternatives to selection at the level of the gene is group selection. But the idea of group selection simply doesn’t work on an evolutionary scale. After all, groups don’t reproduce, only individuals do, and with most species each individual organism is on its own, constantly fighting for survival resources and others to mate with. Individual selection does not encounter the same problems as group selection but has its own set of problems. Individual selection is the view that individuals will always act selfishly, never altruistically, and thus organisms that exhibit cooperative breeding, delayed reproduction, food sharing, alarm calling, and group defense help to prove the falsity of such an idea.

It seems that Dawkins selfish gene theory of evolution, although it does have a few problems, that its core element is correct; that the unit of selection is the gene. After taking everything into consideration, as time goes by, Dawkins and Gould’s theories seem to grow ever closer. With ample evidence in the fossil record to support the idea of rapid evolution followed by pronounced periods of stasis and all the information we have about how phenotypic change occurs it is difficult to deny that Gould’s punctuated equilibrium theory does have some merit, but Dawkins gene-centred view of evolution does too. In time, the gap between these two theories is likely to close further but it will be very difficult for anybody to deny that the gene is the unit of selection. Without genes we do not have the instructions to build an organism, and as such, any change to an organisms genes or DNA can signify a change in the overall organism.