An artistic reconstruction of Isthminia panamensis, a new fossil dolphin from Panama, feeding on a flatfish. Many features of this new species appear similar to today’s ocean dolphins, yet the new fossil species is more closely related to the living Amazon River dolphin. The fossils of Isthminia panamensis were collected from marine rocks that date to a time (around 6 million years ago) before the Isthmus of Panama formed and a productive Central American Seaway connected the Atlantic and Pacific oceans.
Credit: Julia Molnar / Smithsonian Institution