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fossil – n. part of an animal or plant from thousands of years ago, preserved in rock
excavation – n. the act of digging in the ground to look for objects from the past
barefoot – adj. not wearing shoes or other feet coverings
consistent – adj. always behaving or happening in a similar way
mud – n. a thick liquid mixture of soil and water
artifact – n. a simple object made by people in the past
prehistoric – adj. relating to the time before people could write
glacier – n. very large area of ice that moves slowly down a slope or valley or over a wide area of land
