Which of the following statements about communities is not correct? a) many plant species in communities seem to be independently distributed. b) some animal species distributions within a community are linked to other species. c) the distribution of almost all organisms is probably affected, to some extent, by both abiotic gradients and interactions with other species. d) ecologists refer to species richness as the number of species within a community. e) the trophic structure of a community describes abiotic factors such as rainfall and temperature affecting members of the community.