LOS ANGELES (AP) — Scientists are still digging for Ice Age fossils in the heart of Los Angeles after a century of discoveries. So much has been uncovered from the La Brea Tar Pits that crews have a backlog of bones to clean and sort through.

Officials at the George C. Page Museum celebrate 100 years of excavation on Monday with a ceremony. Since 1913, some 5.5 million bones representing more than 600 species of animals and plants have been recovered.

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Fossils finds include mammoths, mastodons, saber-toothed cats and other creatures that lived 11,000 to 50,000 years ago.

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Excavators have been more careful in recent decades to preserve not just the larger bones, but also the smaller plants, insects and rodents that provide a glimpse of the past environment.

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