The grasshopper glacier. Situated in the Beartooth Mountains in Custer National Forest, Montana is an ice formation full of tiny bodies. Discovered in the early 20th century, the original glacier was eight kilometers long but receded to only 0.32 kilometers long today. As it melted away, the ice left behind preserved insect corpses. Frozen in the giant block of ice are tens of millions of grasshoppers, or locusts, many of which are now extinct and have been there for thousands of years.