About 300 fossils of whales and dolphins, discovered in Switzerland and dating from that period, have been examined, allowing researchers at the Institute of Paleontology at the University of Zurich to identify two previously unknown species.
Analyzing portions of teeth, vertebrae, and bones discovered in layers of marine sediment, the scientists looked for the rarely found inner ear bones that help classify the species.
“We have successfully identified two families of dolphins previously unknown in Switzerland,” paleontologist Gabriel Aguirre said in the university’s statement.
Using computer-aided microimaging, a 3D imaging technique, the researchers were able to reconstruct the soft tissue around the ear bones, creating 3D images of the appendages.
“This allowed us to better analyze the auditory capabilities of the dolphins,” Aguirre added.
In their paper, published on the science website PeerJ, the researchers explain that they have demonstrated that the extinct species they identified are related to today’s extant sperm whales and dolphins.
20 million years ago, sharks, fish, dolphins and cetaceans thrived in the sea that covered Switzerland, whose shores were colonized by crustaceans, mussels and sea urchins.
A large amount of fossils have been discovered in the sedimentary layers, known as the upper marine mass.
