The Great Plains of the United States were once home to millions of bison, stretching across the landscape in herds that could take days to pass by. But the arrival of settlers in the 19th century changed that, as the bison were hunted for their meat and hides, leading to a dramatic decline in their numbers. Now, conservationists are facing a new challenge: restoring the bison population to its former glory. The task is made more difficult by the fact that the bison population has been so drastically reduced that the genetic diversity of the species has been severely impacted. This means that the bison that remain are not as genetically diverse as they once were, which could lead to long-term health problems for the species. "We're seeing a lot of inbreeding, and that's a problem," said Dr. Sarah Kline, a biologist at the University of Wyoming. "Inbreeding can lead to reduced fertility, lower disease resistance, and an overall decrease in the health of the species." Kline and her team are attempting to address this problem by introducing new genetic material into the existing bison population. To do this, they have been collecting genetic samples from bison in other parts of the world, such as Canada and Mexico, and introducing them into the existing population. "We're hoping that this will increase the genetic diversity of the bison, which in turn will help to ensure their long-term health and survival," said Kline. The team is also looking at other ways to help restore the bison population, such as reintroducing them to areas where they were once abundant. But Kline stresses that this is a long-term project, and that the genetic challenge is the most important factor in ensuring the future of the species. "We need to make sure that the bison we reintroduce are genetically diverse and healthy," she said. "That's the only way we can ensure that the bison population will be able to survive and thrive in the long run."