bronze age, glacial epoch, glacial period, ice age, iron age, stone age

prehistoric, mesolithic, bronze age, neolithic age, upper paleolithic, antiquity, archeology, neolithic, palaeolithic, paleolithic age, middle paleolithic, ancient, fossils, pleistocene, paleoecology, iron age, aurignacian, palaeontology, triassic period, peopling, anthropological, middle ages, mesozoic era, palaeontological, etruscans, radiocarbon dating, ancestors, megafauna, paleontological, mycenaean, faunas, papyri, minoan civilization, archaeological, mesoamerican, mammoths, jurassic period, devonian period, paleoanthropology, dinosaurs, cenozoic, hellenistic, civilization, archaeologists, conodonts, cretaceous period, iroquoian, caddoan, homo erectus, hominoid, minoans, toltecs, acheulian, algonquian, sumerians, pictographs, homo heidelbergensis, pleistocene epoch, middens, dinosauria, coprolites, archeologists, millenniums, archaeo, origins, olduvai gorge, ethnological, permian period, mesoamerica, hominids, cosmologies, oligocene epoch, archeological, thracians, trilobite, neandertal, folklore, shang dynasty, coprolite, archeopteryx, cenozoic era, avifauna, carolingian, medieval, geomorphology, paleolithic, decipherment, hittites, carboniferous period, stegodon, herodotus, landforms, chalcolithic, ichthyosaur, cambrian period, mousterian, skara brae, lower palaeolithic, genus homo, mound builders, epigraphic, supercontinent, ethnology, archaeology, coasts, mainland, ancestry, coast, coastline, exceptionalism, history, dialects, mythology, provenance, historiography, historv, origin, seacoast

amount of time, period, period of time, time period