34 million years ago, snakes may have already developed the habit of gathering to spend the winter. This practice, similar to that of some current species, has been highlighted by the discovery of a fossil in Wyoming. It indicates that social or survival behaviors in these reptiles date back to a much earlier time than imagined.
The discovery of this fossil, named
Hibernophis breithaupti, comes from the White River Formation in Wyoming. Researchers studied four specimens, three of which were grouped on a single rock block. Thanks to a scanography technique, a third individual hidden inside the rock was revealed, offering a more complete view of the scene.
The fossil skeleton of the newly discovered species Hibernophis breithaupti, which lived 38 million years ago in present-day Wyoming, provides information on the evolution and social behavior of its modern descendants.
Credit: Jasmine Croghan The fossils of
Hibernophis are remarkable for their state of preservation, including skulls, jaws, and vertebrae. This detailed preservation facilitated the identification of a new genus and species. The snake was small in size and likely burrowing, belonging to an ancient North American fauna very different from today's. Before the rise of modern snake groups, constrictors dominated ecosystems.
The anatomy of
Hibernophis shows traits common to early boid snakes and the Charinaidae family, indicating that it might be near an important evolutionary division. This position makes it a valuable specimen, capturing an early stage in the evolution of boa-like snakes. Rather than fitting into existing categories, it shows that snake evolution was probably more gradual and branched than expected.
The environment in which
Hibernophis lived contrasts strongly with current ecosystems in North America. Constrictors played a major role before other lineages took over. This discovery helps fill gaps about this ancient era and indicates that the continent could have had a great influence on the evolution of boa-type snakes. Researchers hope that other fossils will enrich this understanding.
The method used to detect the hidden specimen, scanography, was crucial for this study. An international collaboration, involving paleontologists from Canada, Australia, and Brazil, allowed for in-depth analysis of these fossils. Michael Caldwell, from the University of Alberta, explained that modern snakes like garter snakes gather by the thousands to hibernate, and seeing traces of this behavior 34 million years ago is impressive.