Related by context. Frequent words. (Click for all words.) 73 Cretaceous Period 65 Late Cretaceous 62 interglacial period 59 Pleistocene 58 Cretaceous 57 interglacial 57 Pliocene 56 Carboniferous 56 Eocene 55 dinosaurs roamed 54 Paleocene 54 trilobites 54 fossil 54 marine reptiles 53 Triassic 53 fossils 53 Ordovician 52 Mesozoic 52 fossilized remains 52 prehistoric 52 glaciation 51 dinosaurs 51 Australopithecus afarensis 50 Jurassic 50 hadrosaur 50 Paleolithic 50 dinosaur fossils 50 Oligocene 50 theropod 50 Precambrian 50 vertebrate species 49 Lower Cretaceous 49 Ice Age 49 prehistory 49 sauropod 49 Quaternary 49 Miocene 49 Australopithecus 49 fossilized bones 48 Fertile Crescent 48 tyrannosaur 48 mammal 48 megafauna 48 Younger Dryas 48 Archaeopteryx 48 fossilized 48 dinosaur fossil 48 breeding colony 48 Homo sapiens 47 woolly mammoths 47 plesiosaur 47 tyrannosaurs 47 dinosaur footprints 47 microfossils 47 pterosaur 47 hominins 47 Paleozoic 46 mammals 46 billed dinosaur 46 sauropods 46 sedimentary rock 46 dinosaur 46 western lowland gorillas 46 #BC [003] 45 baleen whales 45 carnivorous dinosaurs 45 marine sediments 45 Neandertals 45 mammoths 45 anatomically modern 45 lake sediments 45 Little Ice Age 45 Mammoths 45 theropods 45 paleontological 45 hominids 44 coelacanth 44 continental crust 44 Devonian 44 amphibian species 44 preindustrial 44 palaeontologists 44 bony fish 44 Ming Dynasty #-# 44 radiocarbon 44 Homo habilis 44 Tiktaalik 44 millenniums 44 multicellular 44 diatom 44 hominid 44 nesting pairs 44 species 44 radiocarbon dating 44 Neandertal 43 extinct 43 Holocene 43 intertidal 43 Ardipithecus 43 millennia 43 Homo erectus