I was perusing an old journal article about docility as an evolved trait.
The article was written by H.A. Simon, in 1990, and was entitled: "A mechanism for social selection and successful alrtuism.", Science, 250, 1665-1668
Here's a link for the abstract of the article: http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract
In short, the article argues that, due to evolution, humans evolved behaviors that would encourage docile traits. Docility, for the purposes of the article, is defined as "...the tendency to uncritically accept social teachings, much the way young children unquestioningly emulate the behavior of parents and older siblings, or even the way in which adults can be compelled into certain beliefs and behaviors by social forces." This docility would've become a desirable trait, as it would encouraged an evolution of emotional responses that bonded groups together. Bonding together was/is a survival tactic.
However, I would argue that the advantage of "fitting in" only retains its value so long as the survival advantages far outweigh the sacrifices one is required to make (for group cohesion) to maintain the group. Another problem is that, while being docile, you put yourself in a position to be taken advantage of. Sure, you may gain acceptance from your peers and endear yourself to the group, but wouldn't the disadvantage far outweigh the advantages? If you stray from the group, and think CRITICALLY, you are ostracized. This biological phenomena, while derived from evolution, might explain the fervor in which some individuals cling to their "group identity" (within religions). It's also interesting to note, from a psychological standpoint, that the consequences of differing from the group also evoke secondary emotions, such as; shame and guilt. These secondary emotions are NOT tied directly to success within the group, but involve a feeling of personal success. So, it seems rather straight forward: if you can mitigate the feelings of guilt and shame, then you have rendered the necessity of the group mentality. Guilt, fear, and envy (all secondary reactions), are not critical for survival. This opens up a whole other can of worms: do people really need churches/religions to propogate these secondary emotions if they're not necessary for survival? I would argue that they don't. They only need to tap into these secondary emotions IF they need to ensure the fecundity of their theology.
Furthermore, given our propensity, as humans, to pick-up on signals conveyed by emotions (wether secondary or primary)...we can easily see how such tactics could lead to an over-dependence on an outside cue (from a church or peers): when, in reality, that's not a biologically sound way to encourage positive growth.
Just my thoughts...it's interesting how evolution explains away the need for religion. Yet, religious leaders often play to the survival instincts of individuals, within a herd, to further their own selfish goals.