Related by context. Frequent words. (Click for all words.) 68 tetrapod 65 Tiktaalik 65 placental mammals 63 toothed whales 63 baleen whale 63 tetrapods 62 theropod 62 plesiosaurs 62 vertebrate animals 62 convergent evolution 61 crocodilians 61 Indohyus 61 phyla 61 carnivorous dinosaurs 60 marine invertebrates 60 planktonic 60 sexual dimorphism 60 vertebrate 60 stickleback 59 morphologically 59 unicellular 59 theropod dinosaurs 59 amphipods 59 feathered dinosaurs 59 primate evolution 59 theropods 58 prokaryotes 58 sticklebacks 58 baleen whales 58 crocodilian 58 mammals 58 species 58 pectoral fins 57 Ardipithecus 57 hominins 57 marine reptiles 57 ecological niches 57 snail shells 57 macroevolution 57 tubeworms 57 trilobites 57 reproduce asexually 57 otolith 57 anglerfish 57 pipefish 56 fossil specimens 56 damselfish 56 H. erectus 56 mammalian species 56 taxa 56 Gansus 56 Xenopus 56 ammonites 56 coelacanth 56 Diplodocus 56 platypuses 56 multicellular organisms 56 Hox genes 56 cartilaginous 55 anthropoids 55 otoliths 55 vertebrates 55 diatoms 55 mottled brown 55 Archaeopteryx 55 morphological 55 faunal 55 avian species 55 multicellular 55 gobies 55 primate species 55 morphologies 55 Australopithecus 55 molluscs 54 tunicates 54 hominid 54 Homo sapiens 54 single celled organisms 54 tyrannosaur 54 echidnas 54 Raptorex 54 subfamily 54 Ardipithecus ramidus 54 single celled 54 sauropods 54 gastropods 54 horned dinosaur 54 H. sapiens 54 apelike 54 hominin 54 Evolutionary biologists 54 Homo habilis 54 clades 54 foraminifera 54 Neandertal 53 sea anemone 53 tyrannosaurs 53 larval stages 53 T. gondii 53 oviduct 53 aquatic mammals