The following appeared as part of a letter to the editor of a scientific journal."A recent study of eighteen rhesus monkeys provides clues as to the effects of birth order on an individual's levels of stimulation. The study showed that in stimulating situ

The letter to the editor tries to provide explanation for effect of birth order on individual levels of stimulation in humans with help of recent study that was conducted on the rhesus monkeys.However, the various evidences provided in the argument provide the scope for alternative explanations that can rival the proposed one.

Firstly, the evidence that the firstborn infant monkeys produce twice the level of cortisol hormone than their younger siblings, does not necessarily indicate that birth order has an influence on the increased stimulation. It can be that elder monkey is trying to be protective about its surroundings which usually happens when one becomes more mature in age. The younger siblings when they are as old as the elder one might also produce the same level of cortisol hormone when they encounter with unfamiliar monkey. Thus, it may have nothing to do with birth order as comparison between siblings is made at unequal ages. If the younger siblings at the same age as elder one produce less hormone, only then the explanation holds.

Secondly, the evidence that first time pregnant mother monkey produces more cortisol hormone than mothers who had several offspring, does not indicate that the birth order has anything to do with simulations. It may be that the other mother monkeys are generally more experienced in dealing with those deliveries than the first time mother, due to this experience they produce the same level of hormone during second , third, fourth etc. If it were the birth order the stimulation would be different for different births.Thus, it is the relative inexperience that is causing the increased stimulation rather than birth order.

In conclusion, the facts provided in the argument may not necessarily lead to the same conclusion as that indicated in the prompt.They may lead to several alternative explanations for individual simulations which can be because of experience or maturity rather than birth order.