Related by context. Frequent words. (Click for all words.) 49 saber toothed tigers 49 ground sloths 49 Florida panthers 48 Jurassic Period 47 prehistoric creatures 46 frogs toads 46 megafauna 46 marine reptiles 45 amphibian species 45 Cretaceous Period 45 Sea otters 44 vertebrate species 44 horned rhinos 44 dinosaurs roamed 44 woolly mammoths 44 overhunting 44 giant tortoises 43 marine reptile 43 mammals 42 species 42 interglacial period 42 California condors 42 lowland forests 42 saber toothed cat 42 Sumatran rhinos 42 longline fishing 42 northern spotted owls 42 grassy plains 42 freshwater turtles 42 gigatonnes 42 Late Cretaceous 41 Sumatran tigers 41 DINOSAURS 41 cetaceans 41 mammal species 41 musk oxen 41 petrels 41 Adelie penguins 41 pikas 41 horned dinosaur 41 flightless birds 41 Pleistocene era 41 trilobites 41 Yellowstone ecosystem 41 lions elephants 40 reptiles amphibians 40 Zimov 40 polar bears 40 dugongs 40 penguin species 40 Sage grouse 40 Critically Endangered 40 habitat fragmentation 40 pygmy elephants 40 Cook Inlet belugas 40 Olive Ridley turtles 39 woodland caribou 39 habitat degradation 39 snakes lizards 39 placental mammals 39 creatures 39 Emperor penguins 39 dinosaurs 39 Iberian lynx 39 Polar bears 39 mastodons 39 arctic tundra 39 Arctic tundra 39 temperate forests 39 yellow legged frog 39 bird species 39 Maui dolphins 38 jackrabbits 38 extinct 38 Steller sea lions 38 Mammoths 38 tyrannosaurs 38 mammoths 38 reptiles 38 tyrannosaur 38 single celled organisms 38 wooly mammoth 38 Pacific walrus 38 frog species 38 Allosaurus 38 federally endangered species 38 habitats 38 breeding pairs 38 Homo sapiens 38 interglacial 37 amphibians 37 gigatons 37 marine turtles 37 waterbirds 37 tigers 37 critically endangered 37 mountain caribou 37 horned rhinoceros 37 leatherback turtles 37 Giant Squid 37 supercontinent