Problems with isotope dating
Today, archaeologists study the great cultural diversity of humanity in every corner of the world.Archaeological study covers an extremely long span of time and a great variety of subjects.Archaeology plays a major role in the study of early civilizations, such as those of the Sumerians of Mesopotamia, who built the city of Ur, and the ancient Egyptians, who are famous for the pyramids near the city of Giza and the royal sepulchers (tombs) of the Valley of the Kings at Thebes.Other sites that represent great human achievement are as varied as the cliff dwellings of the ancient Anasazi (a group of early Native Americans) at Mesa Verde, Colorado (see Mesa Verde National Park); the Inca city of Machu Picchu high in the Andes Mountains of Peru; and the mysterious, massive stone portrait heads of remote Easter Island in the Pacific.Many of the objects left behind by past human societies are not present in the archaeological record because they have disintegrated over time.The material remains that still exist after hundreds, thousands, or millions of years have survived because of favorable preservation conditions in the soil or atmosphere.Archaeological research spans the entire development of phenomena that are unique to humans.
By the time people lived in civilizations, burials and funeral ceremonies had become extremely important and elaborate rituals.
On rare occasions, however, delicate objects have been preserved.
For example, fabrics and flowers were found in the celebrated tomb of Tutankhamun, an Egyptian pharaoh who was buried in 1323 BC.
Archaeology also examines many of the same topics explored by historians.
But unlike historythe study of written records such as government archives, personal correspondence, and business documentsmost of the information gathered in archaeology comes from the study of objects lying on or under the ground Archaeologists refer to the vast store of information about the human past as the archaeological record.