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There are more exciting articles coming in January!


Explore a kelp forest—one of the most productive and dynamic ecosystems on Earth.


Learn how robots help humans.


Find out how people and animals turn light into sight.


Explorer VOL. 15 NO. 3 VOL. 9 NO. 4 DEVELOPMENT TEAM


Vice President and Publisher: Francis Downey Executive Editor: Richard Easby Creative Director: Karen Thompson Explorer Editor: Brenna Maloney Young Explorer Editor: Corinne Rucker Permissions Editor: Jean Cantu Production Specialist: Dreama Karnes-Bynane


DE VE LOP M ENT TE AM


Vice President and Publisher: Francis Downey


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PUBLISHED BY NATIONAL GEOGRAPHIC LEARNING


Art Director and Designer: Karen Thompson Senior Editor: Macon Morehouse Young Explorer Editor: Corinne Rucker Explorer Editor: Brenna Maloney Media Editor: Shannon Hibberd Permissions Editor: Jean Cantu Production Specialist: Dreama Karnes-Bynane Director of Production: Nicole Elliott


PUB LISHE D B Y NATIONAL GEOGRAP HIC LE ARNING


NATIONAL GEOGRAPHIC EXPLORER (ISSN 1541-3357) is published seven times during the school year—September, October, November–December, January–February, March, April, May— by National Geographic Learning, 1125 17th Street NW, Washington, D.C. 20036. Postmaster: Please send address changes to NATIONAL GEOGRAPHIC EXPLORER, PO Box 37863 Boone, IA 50037-28633. Periodical postage paid at Washington, D.C., and additional mailing offi ces.


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Copyright © 2015 National Geographic Learning. All Rights Reserved. Reproduction of the whole or any part of the contents of NATIONAL GEOGRAPHIC EXPLORER without written permission is prohibited. National Geographic, NATIONAL GEOGRAPHIC EXPLORER, and the Yellow Border are trademarks of the National Geographic Society.


Cover: a great white shark 10/15/QGL/1 ISBN: 9781337084017


Cover: a gecko 09/14/QGL/1 ISBN: 9781305472129


PICTURE CREDITS COVER; PAGES 2-3 DAVE FLEETHAM/DESIGN PICS/GETTY IMAGES; PAGES 4-5 © CONSTANTINOS PETRINOS/NATUREPL. COM; PAGE 6 STEPHEN FRINK/GETTY IMAGES; PAGE 7 © ROBERT LAWRENCE; PAGES 8-9 DAVID DOUBILET/GETTY IMAGES; PAGE 9 (DIVER) AARROWS/SHUTTERSTOCK; PAGE 9 (SHARK) DAULON/SHUTTERSTOCK; PAGE 9 (BOTTOM) CLOUDS HILL IMAGING LTD./CORBIS; PAGES 10-11 ALICE NERR/SHUTTERSTOCK; PAGE 12 AP PHOTO/ANDRES MATA FOUNDATION; PAGE 13 © PATRICIO ROBLES GIL/SIERRA MADRE/MINDEN PICTURES; PAGES 14-15 © PHILIP LEE HARVEY/AGE FOTOSTOCK; PAGE 15 (LEFT) DR. MARTIN HINGST; PAGE 15 (RIGHT) © A. JAGEL/AGE FOTOSTOCK; PAGES 16-17 AARON AMAT/ SHUTTERSTOCK; PAGE 17 © ANDREW CASTELLANO; PAGES 18-19 CRAIG MAYHEW AND ROBERT SIMMON/NASA GSFC; PAGE 20 JANICE KELSEY/SOLAR CITIES, INC.; PAGES 20-21 ILLUSTRATION BY ROSALYNN CANTU; PAGE 21 (TOP) PAOLA DI BELLA/REDUX; PAGE 21 (CENTER RIGHT) THOMAS H. CULHANE, PH.D./SOLAR CITIES, INC.; PAGE 21 (BOTTOM) THOMAS H. CULHANE, PH.D./SOLAR CITIES, INC.; PAGE 22 (TOP) SYBILLE CULHANE, PH.D.; PAGE 22 (BOTTOM) JANICE KELSEY/SOLAR CITIES, INC.; PAGE 23 AARON AMAT/SHUTTERSTOCK; PAGE 24 © OSF/DAVID HARING/ANIMALS ANIMALS.


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Copyright © 2015 National Geographic Learning. All Rights Reserved. Reproduction of the whole or any part of the contents of NATIONAL GEOGRAPHIC YOUNG EXPLORER without written permission is prohibited. National Geographic, NATIONAL GEOGRAPHIC YOUNG EXPLORER, and the Yellow Border are trademarks of the National Geographic Society.


NATIONAL GEOGRAPHIC YOUNG EXPLORER (ISSN 1930-8116) is published seven times during the school year—September, October, November–December, January–February, March, April, May— by National Geographic Learning, 1125 17th Street NW, Washington, D.C. 20036. Postmaster: Please send address changes to NATIONAL GEOGRAPHIC YOUNG EXPLORER, PO Box 4002913, Des Moines, IA 50340–2913. Periodical postage paid at Washington, D.C., and additional mailing offices. To subscribe:

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