"Pronghorn antelope are experts at survival. The only ungulate endemic to North America (meaning they evolved here and nowhere else), they're also the only remaining species in their family. They've lived on this continent for 20 million years, about 19.99 million years longer than humans. They shared the plains with American cheetahs and enormous dire wolves, now extinct, plus millions of bison that used to surge over the land. They watched the Teton Range rise up out of the Snake River plain and they weathered ice ages." - Jenny

"One strategy that's helped them prosper for so long is migration, the ability to seasonally cross huge distances of country to seek better climate and habitat. Some of the antelope this winter traversed 250 miles of Montana before they found adequate range south of the reservoir, near the town of Jordan and along Highway 200. When Johnson went there in February, he noticed something strange: the antelope's legs were dark gray rather than the usual white. He found they were scabby and bloodstained with the hair worn off from traveling through brush and crusty snow. Making this difficult journey south of the worst snow paid off at first. The antelope fared well for the rest of the winter and were in good health when spring started to soften Montana, while those that stayed north of the Missouri River died by the thousands from freezing, starvation and collisions with trains when they went up on the tracks to escape deep snow. However, for those that did migrate, their main trial was still ahead, and like the trains, it was something for which evolution did not prepare them." - Jenny

"This is not the first time antelope have faced extreme weather. The last record floods on the Milk River happened just 50 years ago, a mere blink in antelope evolutionary history. But recent landscape changes such as dams, fences and subdivisions threaten migration as a survival strategy for the pronghorn. Add to that, the record 391 parts per million of carbon dioxide in the atmosphere and dire predictions for more extreme weather to come. In an angry Washington Post op-ed responding to flooding throughout the Missouri River watershed plus recent wildfires and tornadoes, climate change activist Bill McKibben wrote, "you might find your thoughts wandering to, oh, global warming, and to the fact that climatologists have been predicting for years that as we flood the atmosphere with carbon we will also start both drying and flooding the planet, since warm air holds more water vapor than cold air." (I recommend listening to a reading of the letter here.) It's this dual threat of human-built obstacles like reservoirs and fences blocking migration on the ground and a shifting climate pushing wildlife to cover more distance in their search for suitable habitat that puts migrating pronghorn in danger. They survived the die-off of prehistoric species and a brush with extinction from overhunting a century ago. Now the landscape these animals evolved with for millions of years is deteriorating. If we can't protect the climate and habitat enough to enable this long-term survivor to continue its ancient journeys, I have to wonder if we're doing enough to protect the land for our own fledgling species." - Jenny