内容摘要：Some of the most tantalizing clues come from an archaeological site in central Brazil, called Santa Elina, where bones of giant ground sloths show signs of being manipulated by humans. Sloths like these once lived from Alaska to Argentina, and some species had bony structures on their backs, called osteoderms — a bit like the plates of modern armadillos — that may have been used to make decorations.

Some of the most tantalizing clues come from an archaeological site in central Brazil, called Santa Elina, where bones of giant ground sloths show signs of being manipulated by humans. Sloths like these once lived from Alaska to Argentina, and some species had bony structures on their backs, called osteoderms — a bit like the plates of modern armadillos — that may have been used to make decorations.

Animal and Plant Health Inspection Service, Uxbridge, Mass. (4,852 square feet)National Park Service, Valentine, Neb. (6,234 square feet)

United States Fish and Wildlife Service, Valley Stream, N.Y. (9,493 square feet)National Oceanic Atmospheric Administration, Wall Township, N.J. (1,768 square feet)Mine Safety Health Administration, Waynesburg, Pa. (8,233 square feet)

United States Fish and Wildlife Service, Winona, Minn. (6,827 square feet)National Park Service, Yankton, S.D. (9,048 square feet)

Office of the Secretary, Anchorage, Alaska (14,805 square feet)

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