9503217 Connell The objectives of this project are to measure the effects of ground-dwelling vertebrates and mycorrhizal fungi on the seedlings and saplings in the shaded understory of an Australian tropical rainforest. The investigators will use field enclosure experiments, greenhouse growth experiments, and quantitative surveys in the field to determine the role of animals and fungi in the maintenance of species diversity in tropical forests. These effects have rarely been studied outside the new world tropics, and seldom tested experimentally anywhere. Second, these effects will be studies with controlled field experiments to test the suggestions from other studies that these animals help maintain plant diversity in rainforests. This is important for wildlife management and the conservation of biodiversity, because large vertebrates are vulnerable to hunting and poaching in parks, and their numbers have been reduced in many tropical rainforests, which could then lead to a decrease in the diversity of trees, among other species, in these tropical forests.