An international team of scientists, including Portuguese paleontologists Carlos Neto de Carvalho and Mário Cachão, discovered the oldest remains of deep-sea fish in the Apennine mountain range in Italy, dating back 130 million years.
The team analyzed fossilized turbidites (sedimentary deposits) from the abyssal plains (extensive area of seabed) of the ancient Tethys ocean (current Mediterranean Sea), from the Lower Cretaceous, and the results obtained allow us to anticipate the appearance of fish in the deep sea in more than 80 million years.
The study, which included the collaboration of Carlos Neto de Carvalho and Mário Cachão, both researchers at the Dom Luiz Institute of the University of Lisbon, was published this week in the scientific journal PNAS and was released this Friday in a statement from Naturtejo — Company of Tourism. Naturtejo manages a geopark that extends through the municipalities of Castelo Branco, Idanha-a-Nova, Nisa, Oleiros, Penamacor, Proença-a-Nova and Vila Velha de Ródão and whose scientific coordinator, Carlos Neto de Carvalho, is co-author of the study.
According to the study, the traces found in the Apennine mountain rangeto the northwest, near the cities of Piacenza, Modena and Livorno, suggest activity since at least three species of fish that fed on invertebrate animals that settled in marine sediments, the observations being “consistent with the transition of Lower Cretaceous vertebrates to the deep sea, caused by the availability of new food sources.”
The remains, the oldest of any deep-sea vertebrate, include track markings sinuous formations formed by the tail of a fish as it swam or excavation marks Bowl-shaped marks left by fish while feeding, describes the Naturtejo statement, adding that these marks are similar to “the structures produced by modern fish that feed by scraping the seabed or exposing prey by suction. They live at the bottom.” According to the scientific team, these behaviors are reminiscent of the Neoteleostei, a group of fish that includes the modern lizard fish.
In the then Tethys ocean, thousands of meters deep, fish had to face “extreme environmental conditions” given its origin in coastal waters: darkness, temperatures close to freezing point and enormous pressures. Such conditions “required adaptations for life on the sea floor that They are evolutionary innovations as significant as those [como membros e asas] which allowed the colonization of land and air” by other species of vertebrates, highlights the same statement.
The study also included contributions from Italian researchers, including Andrea Baucon, first author of the work and who also works in the Naturtejo geopark, as well as Spanish and British researchers.
Source: Observadora
