Extinction (Biology) Biodiversity 2 Climatic changes 2 Effect of human beings on 2 Nature 2 Adaptation (Biology) 1 Biogeography 1 Biogeomorphology 1 Conservation biology 1 Deforestation 1 Ecological disturbances 1 Ecology 1 End of the world (Astronomy) 1 Environmental degradation 1 Evolution (Biology) 1 Global warming 1 Historical geology 1 Mass extinctions 1 Moral and ethical aspects 1 Nature conservation 1 Nature-Effect of human beings on 1 Paleoanthropology 1 Paleontology-Pleistocene 1 Social aspects 1 Sustainable development 1 Wildlife conservation 1