Why are we still so WEIRD? Barriers and bridges towards a diversified science of early development Leher Singh, Alejandrina Cristia, Lana B. Karasik, and Lisa M. Oakes Author NoteLeher Singh, Department of Psychology, National University of Singapore, Singapore; Alejandrina Cristia, Laboratoire de Sciences Cognitives et Psycholinguistique, Département d’Etudes Cognitives, ENS, EHESS, CNRS, PSL University, Paris, France; Lana B. Karasik, Department of Psychology, College of Staten Island & Graduate Center, CUNY, Staten Island, New York, U.S.; Lisa M. Oakes, Center for Mind and Brain, UC Davis, Davis, CA, U.S.A.C., L.B.K., and L.M.O contributed equally to the manuscript. Acknowledgments: We are very grateful to Sarah J. Rajendra for assistance with data collection and processing. This manuscript was supported by sabbatical funds from the National University of Singapore to LS and by Agence Nationale de la Recherche (ANR-17-EURE-0017), the J. S. McDonnell Foundation Understanding Human Cognition Scholar Award, European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (ExELang, Grant agreement No. 101001095) grant awards to AC, National Science Foundation Grant DLS-1349044 and Grant DLS-1528831to LBK.Address for correspondence: Correspondence concerning this article should be addressed to Leher Singh, Department of Psychology, National University of Singapore, 9 Arts Link, Singapore 117570. RUNNING HEAD: Diversifying developmental science AbstractIn developmental psychology, no population has been more relevant to the study of the origins of human behavior than infants. The psychological processes of infants often inform fundamental theories of innateness and/or universality of behavior. However, infant samples are typically small with narrow sociodemographic variation. This review examines changing trends in sociodemographic representation in psychological research with infants. Analyses of 1383 studies, published over the past decade, revealed both consistent underreporting of sociodemographic information and clear skew towards White infants from North America/Western Europe. The impact of these findings on our understanding of and interpretation of research on early human development is discussed. A set of principles and practices are presented to advance towards a more global developmental science.