Just a century ago, bison were on the edge of extinction but are now back in droves with a nationwide count that pushes 400k, though less than 10% are wild. Still, these biodiversity superstars are restoring ecosystems that have long depended on them. Often referred to as buffalo by some Indigenous people, Troy Heinert, a member of the Sicangu Lakota, told the Washington Post, Buffalo is the original climate regulator. Just by how they use the grass, how they graze, how their hoofs are designed, the way they move. They did this job for us when we allowed them to be buffalo.”

Like natural fires that make way for new growth, bison are environmental regulators, grazing grasslands and fertilizing the soil. Their thundering hooves force seeds into the earth, and their thick coats house micro-ecosystems -- work that makes the green plains usable for other creatures. New grass brings "other animals that would feed on it: elk and deer and whatever other type of grazers that would consume some of that new forage,” explains Dan McDonald, lead wildlife biologist at Wichita Mountains Wildlife Refuge.

Bison, though, did not make their glorious comeback on their own. Their population has rebounded with much thanks to efforts made by Indigenous tribes fighting for protective legislation and helping to care for bison herds.