Investment by maternal grandmother buffers children against the impacts of adverse early life experiences: A causal analysis based on instrumental variable regression

Exogenous shocks during sensitive periods of development can have long-lasting effects on adult phenotypes including behavior, survival and reproduction. Cooperative breeding, such as grandparental care in humans and some other mammal species, is believed to have evolved largely in order to cope with challenging environments. Nevertheless, studies considering whether grandparental investment can buffer the development of grandchildren from …