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MARY POPE OSBORNE and NATALIE POPE BOYCE are sisters who grew up on army posts all over the world. Today, Mary lives in New York City and Connecticut. Natalie makes her home nearby in the Berkshire Hills of Massachusetts. Mary is the author of over 50 books for children. She and Natalie are currently working together on The Random House Book of Bible Stories and on more Magic Tree House Research Guides.
Here's what Natalie and Mary have to say about working on Sabertooths and the Ice Age: "We had a great time researching the Ice Age. Natalie used to live near a ranch in Naco, Arizona. One day after a heavy rain, the rancher uncovered some puzzling bones in the dirt. Scientists told him they were the bones of an Ice Age mammoth! There were also bones of many bison, as well as spear points and tools. Ancient remains of other animals like bison, camels, and bears were also found in that part of Arizona. History comes alive when discoveries like this happen so close to home. Imagine... a mammoth might have once walked right where her gar den used to be!"