Week In Science

The website TalkOrigins features an essay entitled 'What is Evolution.' The essay poses the following question:

"What exactly do biologists mean when they say that they have observed evolution or that humans and chimps have evolved from a common ancestor?"

To answer the question Douglas Futuyma's definition is referenced.

"In the broadest sense, evolution is merely change, and so is all-pervasive; galaxies, languages, and political systems all evolve. Biological evolution ... is change in the properties of populations of organisms that transcend the lifetime of a single individual. The ontogeny of an individual is not considered evolution; individual organisms do not evolve. The changes in populations that are considered evolutionary are those that are inheritable via the genetic material from one generation to the next. Biological evolution may be slight or substantial; it embraces everything from slight changes in the proportion of different alleles within a population (such as those determining blood types) to the successive alterations that led from the earliest protoorganism to snails, bees, giraffes, and dandelions."

- Douglas J. Futuyma in Evolutionary Biology, Sinauer Associates 1986

A definition citing change in populations also makes virtually everyone an evolutionist by definition. Who would argue that changes do not occur? On the other hand who would contend that acknowledging change equates to acknowledging the sufficiency of evidence for mainstream evolutionary concepts? The specific data supporting these concepts extends well beyond the simple population change phenomenon noted by Futuyma.

Describing evolution as mere change without referencing actual changes attributable to it is trite. If population changes were all that is conveyed by the term then the word evolution itself would be superfluous. Why not stick with change? Try using the term evolution in any internet discussion group and scientists and non-scientists alike interpret the word as applicable to the broad array of biological change said to have occurred throughout natural history.

The essay author, Laurence Moran, notes confusion about the "precise definitions of biological evolution" and attributes some of this to ineffective communication on the part of scientists. He also goes on to emphasize the importance of distinguishing between theories about evolutionary mechanisms and evolution itself.

Far from being ineffective communicators, evolutionary proponents since Darwin have been brilliant advocates of two dual concepts. The first focuses on scientific data and relates it to theoretical models. Who would argue that this has been ineffectively done? Some cite creationist and intelligent design dissension as evidence of faulty communication but there is much to indicate that it is the second concept that arouses most of the ire from these groups.

It is alluded to in Futuyma's first sentence. Evolutionary change has a broad scope which extends to marginally scientific matters as well as matters that are outside the bounds of empirical studies. Evolutionary concepts are invoked to explain behavioral sciences, social sciences and religion. It is in these areas that critics of evolution not only have powerful arguments, they have powerful incentives too.

Mainstream positions associated with evolutionary concepts find themselves engaged in turf wars. A passage from Margaret Cook's review of Richard Dawkin's book 'The God Delusion' illustrates the point.

"But following this concession, no religious belief is spared in The God Delusion. Chapter two, "The God Hypothesis", is a maniacal dance trampling over the monotheistic religions. The gods may, as he argues, be nasty and the creeds may defy logic. But most of Dawkins's readers are his own congregation, and don't really need to have their noses rubbed so comprehensively in all this. Other educated people aplenty cling to faith even though it is at variance with the logic of daily life: in their minds it occupies a different dimension, and proving scientifically that it is nonsense is irrelevant."

Note the last sentence and the attempt to pass off the inference that faith "is at variance with the logic of daily life" and that it occupies a different dimension. This then is depicted as scientific nonsense. Granted, this is a book review and not a scientific paper. Nevertheless where is the empirical data to support such an opinion? If there is presentable data, is it ambiguous or unequivocal?

"On the topics of the roots of religion and morality, we are on more traditional evolutionary territory. Yet Dawkins is less than comfortable in the realms of psychology (he refers to an "evolutionary psychiatrist", a non-existent species). He does not explore the alpha-male reincarnation of Abrahamic gods. His opinions on abortion and euthanasia seem to have been hurriedly formulated for the purpose of this book."

If Dawkins is uncomfortable with evolutionary psychology then we at least might have something in common.

"Dawkins's theory that organised religions are a "by-product" of natural selection is, on the other hand, entirely credible. Both the hierarchical structures and the tribal "in-group morality and out-group hostility" of religious institutions are clearly traced, in The God Delusion, to phases in archaic socio-sexual structures. But his examination of the origin of individual religious awareness, the nub of the matter, is inadequate. It was probably our ancestors' first consciousness of personal demise that created the need for the supernatural, but Dawkins makes no reference to burial of the dead and the grave-goods that accompanied them. This is surely the pivotal event that enabled prehistoric man to overcome the horror of his own physical end and gave him a false but sanguine belief in eternal life that proved to have survival value."

Turf wars? There it is. How often have I encountered the contention that the supernatural is beyond the capacity of science to evaluate. It is difficult to traverse critiques of intelligent design without observing this very point being made against alternatives to mainstream evolutionary theories. But what is good for the goose should suffice for the gander as well. If the supernatural is beyond empirical studies then it is also beyond empirically based critques. Natural selection cannot be invoked as an explanatory device to explain a belief in God. If it is, it is a form of natural selection unlike the scientifically based concept which I will introduce next.

In the abstract of a paper entitled 'Long intervals of stasis punctuated by bursts of positive selection in the seasonal evolution of influenza A virus,' the authors point out the following:

"The interpandemic evolution of the influenza A virus hemagglutinin (HA) protein is commonly considered a paragon of rapid evolutionary change under positive selection in which amino acid replacements are fixed by virtue of their effect on antigenicity, enabling the virus to evade immune surveillance."

Amino acid changes in a viral protein enabling it to evade immunological responses of a host organism is a classic example of selection in action. The viruses can be tested, results are observable and the data obtained is clearly scientific. Contrast this with the "scientific claims" found in the book review. Evolutionary critics may argue that the data associated with viral adaptation does not support a self-replicator-to-man paradigm but the data itself is not a divisive issue.

Added fuel to the fire comes in the form of ideological bias. Self-appointed guardians of scientific integrity are quick to pounce on claims made by creationists and IDers when, in their estimation, they fall short of the mark. But soft scientific cases referencing social and religious values don't arouse that same passion for integrity. There are unacknowledged ideological motives among some in the scientific community which escape in-house scrutiny.

Threats posed by creationists and IDers have been overplayed. The more subtle threat from within, that seeks to take science to places it has no business going, is the one in need of remedy.