A few years ago, a group of Native American leaders drove 12 hours from Oklahoma to Denver Museum of Nature and Science, a natural history museum in the Rocky Mountains of Colorado, to collect 26 sets of human remains. When Chip Colwell, the museum’s senior curator of anthropology, explained to them that, though the remains were fragments from people that populated the Great Plains, he didn’t know from which tribes, they were shocked: ‘The room plunges into silence,’ he recounts, followed by ‘heated deliberation’.