Carnivores and bulk herbivores get real big. Omnivores and insectivores fit in between and have throughout the age of mammals. This data dense study shows how long this trend has existed and what is happening to it now. The study also suggests that human related extinctions of the largest herbivores and carnivores are disrupting what appears to be a fundamental feature of past and present ecosystems, with potentially unpredictable consequences. Amazing project.