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Experiencing the Lifespan

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Experiencing the Lifespan

FOURTH EDITION

JANET BELSKY

Middle Tennessee State University

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FOR DAVID

A world-class intellectual and the world’s best possible husband

Publisher: Rachel Losh

Associate Publisher: Jessica Bayne

Senior Acquisitions Editor: Christine M. Cardone

Developmental Editor: Elaine Epstein

Assistant Editor: Catherine Michaelsen

Editorial Assistant: Melissa Rostek

Editorial Intern: Daria Kaczorowska

Marketing Manager: Lindsay Johnson

Marketing Assistant: Allison Greco

Director, Content Management Enhancement: Tracey Kuehn

Media Editor: Lauren Samuelson

Photo Editor: Sheena Goldstein

Art Director: Diana Blume

Cover and Interior Designer: Blake Logan

Managing Editor: Lisa Kinne

Project Editor: Julio Espin

Production Manager: Sarah Segal

Art Manager: Matthew McAdams

Composition: codeMantra

Printing and Binding: RR Donnelley

Cover photo: Stephen St. John/National Geographic Creative

Photo of brain icon: RENGraphic/Getty Images

Photo of flame icon: rilora/Getty Images

Library of Congress Control Number: 2015942394

ISBN-13: 978-1-4641-7594-7

ISBN-10: 1-4641-7594-2

© 2016, 2013, 2010, 2007 by Worth Publishers

All rights reserved.

Printed in the United States of America

Second printing

Worth Publishers

One New York Plaza

Suite 4500

New York, NY

10004-1562