An article I read looked at a study published in Evolution, Medicine and Public Health, proposed an evolutionary reasoning as to why babies cry at night. The research proposed that babies consciously or unconsciously cry to their mother to prevent the birth of a new sibling that would ultimately end up mean competing for resources, and subsequent survival. Apparently this sort of behavior does have an effect on mothers: nursing a child, especially at night, can stop women for resuming ovulation as essential for reproduction. In this case, the baby is somehow employing a “survival of the fittest” mentality. Of course, many doctors do not agree, and argue that on the contrary, the nightly breast feeding may be cooperation as both baby and mother may benefit nutritionally and in terms of general health.
I personally jumped to Bonita’s presentation today about possible evolutionary theories behind anxiety, and I think the basis of attachment theory – the attachment a child has for his or her mother – causes anxiety may be the only basis of the child’s crying. It may be an anxiety of an inset fear of being separated from the mother, even if she is nearby that could cause crying fits, and as a child matures that anxiety is quelled with logic and understanding. Otherwise, looking at the theory proposed by the study, I do not see why a baby would EVER stop crying even after it matures into a child or older, at least until 15 or 16. Up to that point, it would still have a certain concern of competing for resources or attention and would not stop crying at night until it no longer was dependent on the mother for resources or survival. Of course, I am not an evolutionary biologist, so the theory might not be as ridiculous as it sounds to me, but I would personally need to see a LOT more research before I believed this one.