Clues You need to know what you are looking for when you do this. This is an important part of any dig. Although some are small, a lot of important pieces can be found here. We re screening for fossils.
Fossils are old and usually covered by rocks and dirt.
Over time, the dry, arid ground of areas where we anthropologists frequently look for fossils can be worn and eroded away. This weathering of the earth often exposes covered fossils. When we find important fossils on the surface, we might decide to carefully dig into the ground to see if there are more. This is called excavating. Excavating is the best way to find fossils because we know those fossils have not been disturbed since the time they were buried.