In prehistoric times, the steppe bison (Bison priscus) was an extremely common bovid, whose area of distribution extended across a zone that now covers England to America and the north of Russia to Spain and France. It greatly impressed the first modern humans in Europe, who often represented it in caves like those of Chauvet or Trois-Frères in France, or that of Altamira in Spain. Despite the abundance of skeletal remains and the symbolic importance of this animal, only a small part (5%) of its mitochondrial genome was known until now. A team from the CEA-IBITECS, integrated within the eco-anthropology and ethnobiology laboratory (CNRS/MNHN) located at the Musée de l'Homme, was able to determine the complete mitochondrial genome of a steppe bison specimen from a bone fragment dating back 19,000 years, found in the Trois-Frères cave (Ariège).
The sample was selected in collaboration with the Association Louis Bégouën and the Direction Régionale des Affaires Culturelles Midi-Pyrénées. Phylogenetic analysis of its genome helps position it in the evolutionary tree of bovids, and particularly shows its genetic proximity with the North American bison (Bison bison). Indeed, the mitochondrial genomes from the prehistoric steppe bison and the current bison in North America only differ by around one hundred nucleotides out of a total of 16,300. This study provides a reference sequence, which can be compared with other extinct bison species from the Ice Age. The same team previously determined the complete mitochondrial genome of the cave bear (Ursus spelaeus) from a 32,000-year-old bone found in the Chauvet cave (Ardèche).