- Reintroducing bison to grasslands increases plant diversity, drought resilience. Compared to ungrazed areas, reintroducing bison increased native plant species richness by 103% at local scales. Gains in richness continued for 29 y & were resilient to the most extreme drought in 4 decades. https://www.pnas.org/doi/abs/10.1073/pnas.2210433119 612 comments science