Story behind the science: Yellowstone Wildlife Diets

Story behind the science: Yellowstone wildlife diets

Rethinking how we classify animals based on what they eat—and what it means for wildlife management

An article by science journalist Livi Milloway chronicles an "ah-ha" moment we had in our Yellowstone National Park research project. The story published in The Wildlife Society Bulletin, titled An herbivore by any other name, unpacks how Hannah Hoff's recent paper in PNAS challenges the status quo when it comes to how scientists study and understand wildlife diets. 

With some great photos of Hannah in the field, this article starts at the beginning of our program's work studying the diets of large herbivores in East Africa. These early DNA-based studies of wildlife diets tended to reveal strong dietary niche partitioning -- consistent and statistically robust differences in the foods that animals eat, depending on their species. Dietary niche partitioning is a critically important phenomenon, where it exists, because it enables us to make clear predictions about everything from animal evolution and behavior to how environments will respond to perturbations like climate change.

Equally important but less widely understood, however, are the conditions that allow members of different species to maintain broadly overlapping diets. This is what we've found in the herds of migratory wildlife from Yellowstone.

As the article details, our big "ah-ha" moment is that we often default to treating members of different species as if their diets should be different. This allows us to measure what does make their diets different, even when those differences are minute. But it can divert our focus from the main headline in cases where members of different species -- somehow -- appear to coexist despite extensive dietary overlap.

Drawing inspiration from paradigm-shifting moments in the history of how scientists have studied human evolutionary genetics, Hannah Hoff recognized this was a problem and came up with an extremely innovative strategy to help solve it.

​Find all the details in The Wildlife Society's article An herbivore by any other name.