David F. Bjorklund - How Children Invented Humanity

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Oxford University Press 2021

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Library of Congress Cataloging-in-Publication Data

Names: Bjorklund, David F., 1949- author.

Title: How children invented humanity : the role of development in human

evolution / by David F. Bjorklund.

Description: New York, NY : Oxford University Press, [2021] |

Includes bibliographical references and index.

Identifiers: LCCN 2020016683 (print) | LCCN 2020016684 (ebook) |

ISBN 9780190066864 (hardback) | ISBN 9780190066888 (epub) |

ISBN 9780190066895

Subjects: LCSH: Evolutionary psychology. | Human evolution. |

ChildrenEvolution. | Developmental psychology. | Child development. |

Child psychology.

Classification: LCC BF698.95 .B56 2021 (print) | LCC BF698.95 (ebook) |

DDC 155.7dc23

LC record available at https://lccn.loc.gov/2020016683

LC ebook record available at https://lccn.loc.gov/2020016684

To Sage and Amelia

It may be self-evident that our ancestors developed, but the idea that changes over the course of growing up contributed to evolutionary change has not always been welcome in mainstream evolutionary theory. As I discuss in show in this book, a major player in explaining how Homo sapiens came to be the species we are today.

This book can trace its genesis to three papers I published in the journal Child Development over the span of more than 20 years. In the initial 1997 paper titled, In Search of a Metatheory for Cognitive Development (or, Piaget Is Dead and I Dont Feel So Good Myself), I argued that, with the demise of Piagets theory as a guiding light for cognitive development, the field should look to developmental biology as a metatheorya common set of broad, overarching assumptions and principlesto guide research and unify the field. In particular, I suggested that a better understanding of both proximal (for example, brain development) and distal (evolutionary) biological factors would greatly enhance psychologists understanding of cognitive development. Over the next 20 years I spent the bulk of my scholarly efforts in the field of evolutionary developmental psychology, culminating in the publication in 2018 of A Metatheory for Cognitive Development (or Piaget Is Dead Revisited), where I argued that evolutionary theory was well on its way to becoming a metatheory, not just for cognitive development, but for developmental psychology more broadly, and that an evolutionary perspective can help us achieve a better understanding of development. In a follow-up paper titled How Children Invented Humanity, I turned this argument on its head, arguing that a developmental perspective can help us achieve a better understanding of evolution. In addition to giving the current book its title, many of the ideas presented in this short (four-page) paper served as the jumping-off point for what Ive written here.

This book does not ignore the question of how an evolutionary perspective can help us better understand contemporary development; the fact that I view individual development intimately entwined with evolution requires that both sides of this evolutiondevelopment relationship be examined. In some respects, this book is an extension of my 2007 book, Why Youth Is Not Wasted on the Young, in which I argued that infants and children have an integrity of their ownas individuals with abilities and characteristics that have evolved to be especially suited to the environments they inhabitand that immaturity is not a necessary evil but may play an adaptive role in childrens lives and development (see especially ).

I have enjoyed writing this book, which has helped me to organize my own thoughts on the relation between evolution and development and the consequences the relationship has for understanding both concepts, as well as for the implications it has for rearing and educating children. I hope it strikes a similar chord with readers.

David F. Bjorklund

Jupiter, Florida

I would like to thank my editors at Oxford University Press, Abby Gross and Katharine Pratt, as well as the rest of the Oxford team, for their support in publishing this book. I would also like to thank my former students, friends, and colleagues for their comments on earlier drafts of these chapters, including Ariel Bartolo-Kira, Charles Dukes, Karen Machluf, Alyson Myers, and Patrick Douglas Sellers II. I want to especially thank my friend and colleague Carlos Hernndez Blasi for his encouragement and valuable feedback on every chapter of this book. And my special thanks goes to my wife Barbara Bjorklund for her constant love and support, as well as providing constructive comments on each chapter of this book.

Figure 1.1. Amelia, the most beautiful baby in the world, who just happens to have facial characteristics that adults find adorable. These include fat cheeks, flat nose, rounded and large head relative to body size, and large eyes relative to head size. Combine them with a big grin and eye contact, and its hard not to fall in love with her, or any baby who displays them.

Source: Photo by Heidi Tobiaz, with permission.

We dont stay cute forever. Our chins and foreheads protrude, the eyes stay about the same size as the head gets larger, the cheeks thin out, and our heads come to constitute a smaller percentage of our overall body size, with men showing more of these changes than women. Yet in another sense, as adults we remain cuter, that is, more infantile, than our primate cousins, who also start off with features their parents apparently find appealing. Unlike humans, however, other primates show more drastic changes in face morphology as they age. Human and great ape (chimpanzees, bonobos, gorillas, and orangutans) babies really look quite a lot alike as infants, although the simians show much greater facial changes as they get older, as can be seen in the accompanying photographs (common ancestor with chimpanzees, have retained many infantile features, slowing some aspects of development in comparison with our ancient ape ancestors. This process is called neoteny, literally holding youth, and characterizes a number of aspects of human evolution. The consequences of