Environmental ecology-- Island ecology-- Desert Ecology 40 History 37 Islands 18 Novel 18 Literature 11 Social life and customs 10 Climatic changes 9 English fiction 9 Literature English 9 Tourism 9 English 8 Folk music-India 8 Literature & Fiction 8 Mathematics 8 Manners and customs 7 Mathematical Statistics 7 Novel English 7 Tribes 7 American fiction 6 Ecology 6 Economic development 6 Ethnology 6 Fiction; English Literature 6 General history of Asia - Japan & adjacent islands 6 Tikopia (Solomon Islands people) 6 Women 6 Fiction 5 Human ecology 5 Andaman Islands 4 Botany 4