Guest post & graphics by Nitin Sekar, Princeton University

A seedling germinates from elephant dung.

All around the planet, the world’s largest animal species are becoming very rare. Whether we speak of giant tortoises, large wild cows like gaur, rhinoceroses, hippos, tigers, or whales, local extinction or extreme reductions in range size and population are the norm for species that are too big or too slow-reproducing to withstand human conflict or the human hunter. Most people would probably agree that it is a shame to lose these species. But what about functionally? Are the largest animals critical to any ecological processes? When there are declines in honey bee populations, human agriculture suffers; if nitrogen fixing plants are absent from a forest, other plant species may be affected. When the largest animal species go missing, do any other species miss them? Aside from a few cases, we don’t know! This is an active area of research.

We decided to explore the role of Asia’s largest land mammal—the Asian elephant (Elephas maximus)—in seed dispersal, which helps maintain the diversity of tropical forests. Continue reading →