I would bet pretty hard on option #3. The older the parents are at the time of conception, the lower the quality of their gametes, which can translate into various negative health and cognitive effects on the child.
I think Greg Clark has stated his new book will claim none of the observed status-related birth order effects commonly cited actually exist in a dataset with sufficient size and resolution.
I would bet pretty hard on option #3. The older the parents are at the time of conception, the lower the quality of their gametes, which can translate into various negative health and cognitive effects on the child.
I think Greg Clark has stated his new book will claim none of the observed status-related birth order effects commonly cited actually exist in a dataset with sufficient size and resolution.