During the Jurassic and Cretaceous (between 201 and 66 million years ago) the current Iberian Peninsula was a large island within the Tethys Sea. This tropical sea, precursor of the current Mediterranean, was dotted with numerous islands, forming a large archipelago in its central area.
A new study analyzes how charophytes (a group of aquatic plants) were distributed in this archipelago between 130 and 120 million years ago, during the Barremian and early Aptian, in order to study how the effects of insularity were manifested in the different species that lived there.
The study was carried out by a team made up of researchers from the Faculty of Earth Sciences and the IRBio of the University of Barcelona (UB), the Catalan Institute of Paleontology Miquel Crusafont (ICP), the University of Vienna in Austria and the Institute National Polytechnic (IPN) of Mexico
The results of the study show that the archipelago contained a flora different from that of the neighboring continents and that it was characterized by the diversity of endemic species of the Clavatoraceae family.
Although the islands were separated, the flow of populations between the islands must have been good, since no major taxonomic differences are observed between them.
Within the archipelago, some floristic patterns are observed, both latitudinal (related to climate) and longitudinal (probably related to animal dispersal vectors).
On the other hand, the islands of the archipelago present the first record of some species that would later be distributed in large areas of the planet, including species that would become cosmopolitan in a latitudinal strip.
The comparison with ostracods, crustaceans that often lived in charophyte meadows, shows that these biogeographic patterns could be extrapolated to other groups of the same archipelago, forming what would probably be a differentiated bioprovince.
By: www.noticiasdelaciencia.com/art
World paleogeographic map of the boundary between the Barremian and the lower Aptian (between 129 and 120 million years ago) (Image: Institut Català de Paleontologia Miquel Crusafont)