Related by context. Frequent words. (Click for all words.) 62 terrestrial ecosystems 60 habitats 59 species 58 aquatic habitats 58 taxa 58 lava tubes 58 megafauna 58 plankton blooms 58 habitat 57 temperate forests 57 landmasses 57 intertidal zone 57 planktonic 56 intertidal 56 glaciations 56 deciduous forests 56 phytoplankton blooms 56 inter tidal 56 freshwater marshes 56 marine reptiles 55 habitat fragmentation 55 overwintering 55 caribou herds 55 upwellings 55 faunal 55 nitrogen fixation 55 grassland habitat 54 mammals 54 skink 54 marine sediments 54 temperate regions 54 wetland ecosystems 54 desiccation 54 forbs 54 corals 54 temperate zones 54 barrens 54 landforms 54 termite mounds 53 Sea otters 53 reintroductions 53 subarctic 53 crocodilians 53 ecosystems 53 freshwater ponds 53 seamounts 53 overwinter 53 vegetation 53 reefs 53 vertebrate animals 53 Adelie penguins 53 insect populations 53 biogeochemical 53 avian species 53 stoneflies 53 nesting habitat 53 poleward 53 genetic variability 52 diatoms 52 red legged frogs 52 ptarmigan 52 biodiversity hotspot 52 diatom 52 forested wetlands 52 biodiversity hotspots 52 eel grass 52 mid latitudes 52 foraminifera 52 middens 52 mosses 52 grassland birds 52 Amazonian rainforest 52 seagrasses 52 beaver ponds 52 marine invertebrates 52 acidic soils 52 abiotic 52 petrels 52 atmospheric circulation 52 glacial retreat 52 stickleback 52 fox squirrels 52 lynx habitat 51 embayment 51 arid regions 51 kelp forests 51 amphibian populations 51 morphologically 51 denning 51 flycatchers 51 lowland forests 51 pine marten 51 evergreen forests 51 subspecies 51 aquatic invertebrates 51 lowland 51 speciation 51 cordgrass 51 platypuses 51 pronghorns 51 migratory routes