Even if Aarssen is correct in postulating a “parenting drive”, such a drive would not be an adequate reason for the choice to have a child. Naturalness alone is not a justification for an action. It is still reasonable to discuss whether humans should give in to their alleged “parenting drive” or resist it.
Additionally, growing numbers of women do not experience this drive or do not experience it strongly enough to act upon it. As psychologist Leta S. Hollingworth noted, “There could be no proof of the insufficiency of maternal instinct as a guaranty of the population that the drastic laws which we have against birth control, abortion, and infant desertion.”
In terms of baby fever, it has nothing to do with biology and is a social construct. Reproduction does not require any inherited preference to have children since natural selection already favors mechanisms that result in reproduction, such as through the sexual urge.
To counter the argument regarding the mice study, the scientists doing this research never claimed they found “mommy genes”. It was the exaggeration and misinterpretation of the media. Humans are more complex than mice, and their behavior is more dependent on context and personal experience.