Overview
- Michigan State University ecologists report Monday in PNAS that late‑Pleistocene die‑offs of large mammals left enduring marks on today’s food webs.
- Using records of who eats whom at 389 tropical and subtropical sites, the team compared more than 440 mammal species across the Americas, Africa, and Asia.
- The Americas, which lost over 75% of mammals heavier than about 100 pounds in the last 50,000 years, now support fewer prey species that are smaller and less varied.
- Predators in the Americas tend to hunt prey with a narrower range of traits, a pattern the authors link to past losses that thinned the lower rungs of ancient food webs.
- An example from South America shows how the extinction of giant deer removed key prey for saber‑toothed cats and dire wolves, and the authors now plan tests of whether such historical gaps make today’s communities more vulnerable as many large mammals face IUCN-listed threats.