Open Peer Commentary
Integration of different lines of research concerning grandparental investment appears to be both promising and necessary. However, it must stop short when confronted with incommensurate arguments and hypotheses, either within or between disciplines. Further, some hypotheses have less plausibility and veridicality than others. This point is illustrated with results that conflict previous conclusions from evolutionary psychology about differential grandparental investment.
Grandparental investment: Past, present, and future David A. Coall and Ralph Hertwig School of Psychiatry and Clinical Neurosciences, University of Western Australia, Fremantle, Western Australia 6160, Australia. firstname.lastname@example.org http://www.uwa.edu.au/people/david.coall; Department of Psychology, University of Basel, 4055 Basel, Switzerland. email@example.com http://www.psycho.unibas.ch/hertwig