Archaeologists study the ancient and recent human past through material remains. They are interested in how people of the past lived, worked, traded with others, moved across the landscape, and what they believed. Archaeology is a diverse field of study, and most archaeologists focus on a particular region of the world or a specific topic of study. Specialization allows an archaeologist to develop expertise on a particular issue. Some archaeologists study human remains (bioarchaeology), animals (zooarchaeology), ancient plants (paleoethnobotany), stone tools (lithics), etc. . Some archaeologists specialize in technologies that find, map, or analyze archaeological sites. Archaeologists use a statistical sampling method to select which squares or units they will excavate. They collect surface artifacts, then remove any ground vegetation. Archaeologists screen all soil removed from a unit to recover small artifacts and ecofacts. They record the exact location, both horizontally and vertically, of all materials recovered. Archaeologists spend much more of their time in the laboratory analyzing artifacts and data than they do in the field. They analyze artifacts, features, and other information recovered in the field to help answer their research questions. Archaeologists also delve into historical documents, translate ancient hieroglyphs, conduct interviews to learn about a culture’s oral history, and measure tree rings to find evidence of climatic shifts. Archaeology is based on the scientific method, and archaeologists ask questions and develop hypotheses. They use evidence to choose a dig site, then use scientific sampling techniques to select where on the site to dig. They observe, record, categorize, and interpret what they find. Then they share their results with other scientists and the public.