There is an increasing propensity to attribute morals (and the current lack of violence in society) to physical traits that are subject to development by evolution. This tidy definition of morals as scientific responses to stimuli which is passed on genetically has a few major flaws which I’m aiming to point out here. Obviously I can not cover the entire gamut of this issue in a single post, but I’m hoping to lay out a beginning here and continue in other posts.
Morals can not be the product of evolutionary history. The evidence for this is very simple, morals vary dramatically over short time periods. Evolutionary theory can not (currently) account for social norms, only for physical traits acquired or lost through many generations of progress. Though some studies on the RTPJ (cf. Rebecca Saxe and her work at MIT’s Saxelab) have concluded that there is a developed region of the brain regarding interpersonal communication, and consequently morals, there is no way to account for changing morals among a populace over small time periods (like the move from slavery being encouraged to being completely unacceptable over a matter of a couple of centuries.) This has to be explained by some other means as that is not time for many multiple generations to genetically weed out the change. So it is with many other morals (punishments for theft, freedom of speech, civil rights, etc.) There is simply not enough time for morals to be altered due to genetics in the swiftness with which they can change. The timeline for a change like the slavery change mentioned above, would require an enormous death toll of people who supported slavery, and despite the death toll of even the American Civil war (in which one must remember that both pro- and anti- slavery people were killed in roughly equal number) the toll is not nearly high enough to have converted this issue from one of passive acceptance, to one of active rejection due to biology alone.
Evolutionary history also encounters trouble in the variance of morals from one culture to another. A simple look at the difference in regional morals in treatment of women, acceptance of different world views, punishment for crime, and even the list of crimes, shows that morals are not the same in different cultures. To take an extreme example of this, the recent story of a rape victim being subjected to 90 lashes for “Illegal mingling” (that is relations with someone outside of her marriage) would illustrate the difference of morals between Western cultures and those of the Middle East. The obvious question here (in light of the evolutionary theory of morals) would be, are people in the Middle East less evolved than those in the West?
The question of levels of evolution in morals is, probably, the biggest sticking point of this whole argument. It is nice to say that morals have evolved with us, but then how do we account for someone being able to change their morals due to religious or cultural conversion? Are morals simply a biological self-preservation among a society? If so, how do some people stand up for what is right in the midst of injustice? If not, how can a person’s morals change readily when moving between groups? This is the largest area in which a great deal of evidence of the scientific effect of regions of the brain, like the RTPJ, are needed to shore up this argument. It is possible there is a combination of self-preservation as well as societal good, but the two are often incompatible.
The biological theory also fails on the sense of personal preservation versus societal preservation. There is no benefit gained from some things being immoral, though they are. Murder, for example, is highly beneficial to other species ([warning: graphic links] lions come to mind, or chimpanzees) but is considered immoral to humans, and is treated as a necessary evil at best (which is another, interestingly human concept that does not fit tidily into evolutionary theory.)
All in all, the onus of evidence is on the person trying to argue that morals are developed from the evolution of humans rather than from some absolute which is above change. Though a simple counter to this argument is that morals have not been absolute in the history (or the variety) of religion, this counter is not a proof that morals are necessarily biological, it is a redirect. The argument that morals are absolute is a necessary component to religion, but it is not based in religion, rather in a proper view of the workings of nature.