What is peculiar about human species is that women’s reproductive system ceases functioning a long time before it comes to the expiration of their life time. There is a theory which suggests that the given phenomenon may be explained due to the evolutional reasons as grandmother contribution to raising next generations has played a certain role throughout the history of the mankind.
In other words, the existence of human grandmothers could be one evolutionary advantage that allowed the humankind to become what it is today — the most impactful species on Earth.
Grandparenting and longevity
2 studies looked at this issue recently, Science Daily reported.
The author of the first study, Virpi Lummaa of the University of Turku, Finland, states that despite grandmothers’ help being vital to a family in terms of child care, the efficiency of this function gradually declines depending on the age. In other words, older grannies are not as helpful around the kids as the younger ones.
Lummaa’s team checked the importance of grandmother’s age and how relevant it is for the benefits of her input in the family.
To find the answer, scientists studied different situations where such help took place and wasn’t given. By researching historical data from Finnish church chronicles covering the 16th and 17th centuries, the group found that the people of that period were going through challenging times and had relatively low survival rates, especially among children under 5.
Nevertheless, the presence of a maternal grandmother (mother’s mother) aged from 50 to 75 considerably improved the chances of her grandchildren to survive. Still, with a paternal grandmother aged over 75 children were more likely at risk than when a mate the mother’s mom was available. Interesting, right?
This group concluded that grandmothering may be of great assistance, but definitely there is a certain limit for its beneficial effect. As Simon Chapman, the lead author, suggests, grandmother’s age restricts her ability to help.
Geographical distance vs. grandmothering effect
The leader of the other study group, Patrick Bergeron representing Bishop’s University (Canada), expressed the view that having a maternal grandmother may also influence the number of children in a family as well as their ability to survive the threshold of 15 years. Moreover, the scientist reports that the scale of grandmother’s impact is generally conditioned by the geographic distance between a grandmother and her daughter. The further away, the weaker the helpful impact.
Focusing on this issue, the team headed by Sacha Engelhardt carefully studied the information about the first French settlers to Canada.
Owing to the tendency towards large families back then, the scientists were able to compare the reproductive data of sisters living with and without their mother. The investigation has shown that grandmother’s presence positively influenced both the number of children and their chances of survival to 15 years. At the same time, increase in the geographical distance between the grandmother and her daughter proved to be detrimental for the same ratings.
Grandmothers rock!
Both researches managed to conform the “grandmothers hypothesis” in terms of the contextual factors meaningful for different populations in definite historical periods.
However, since it was customary during the history for women to marry far away, this factor may be not of such a great importance, as scientists thought. Then, the question of women’s early reproductive decline remains.
Nowadays women give birth later and grandmothers usually aren’t too keen to help with young kids. So, the function of the matriarch of the family may not be as helpful — or is it? What do you think? Comment below!
Share this article
CommentsКомментарии ( 0 )