Effect of human beings on Nature 619 Human ecology 248 History 191 Climatic changes 115 Environmental conditions 103 Environmental aspects 90 more ... Ecology 89 Social aspects 87 Environmental policy 59 Environmental degradation 55 Global environmental change 48 Human beings 47 Effect of environment on 44 Environmentalism 38 Philosophy 38 Environmental protection 37 Human-animal relationships 32 Pollution 30 Landscape changes 29 human ecology 26 Social conditions 23 Political aspects 22 Environmental sciences 21 Nature conservation 21 Global warming 20 Human geography 20 Natural history 20 Environmental ethics 19 Extinction (Biology) 19 less ...