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Evolutionary psychology's notion of differential grandparental investment and the Dodo Bird Phenomenon: Not everyone can be right

Published online by Cambridge University Press:  09 April 2010

Martin Voracek
Department of Basic Psychological Research, School of Psychology, University of Vienna, A-1010 Vienna, Austria.
Ulrich S. Tran
Department of Clinical, Biological, and Differential Psychology, School of Psychology, University of Vienna, A-1010 Vienna, Austria.
Maryanne L. Fisher
Department of Psychology, St. Mary's University, Halifax, Nova Scotia, B3H 3C3, Canada.


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.

Open Peer Commentary
Copyright © Cambridge University Press 2010

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