The genetic tests conducted by the Department of Functional Biology have proven the first first known case of viable hybridization between species of pilot whales and, at the same time, the first and only documented between species of cetaceans
A research conducted in collaboration between scientists from the Department of Genetics of the University of Oviedo and the Project of Marine Mammals of the Spanish Institute of Oceanographics (IEO), and the participation of colleagues from several other organizations, describes for the first time in history the existence of a fertile (post-F1) between common pilot whales and tropical pilot whales.
The results of the research, recently published in the prestigious journal PLOS One, are part of the Thesis of Laura Miralles, researcher of the Department of Functional Biology of the University of Oviedo. With the collaboration of the Spanish Institute of Oceanographics, the Asturian research group conducted a genetic study of the samples taken from animales stranded in different parts of the planet (Feroe Islands, Galicia and the Canary Islands).
Furthermore, Laura Millares completed an international research stay at the Centre de Recherches Insulaires et Observatoire de l'Environnement (CRIOBE) in French Polynesia to widen the number of samples for the research and continue her work.
The scientists are trying to determine the origin of the hybridization between both species of pilot whales and limit their geographical localization.
Pilot whales are ceteans of an average size that appear relatively frequently on our coasts. Two species are thought to exist: the common pilot whale, which typically lives in the cold waters of the north of Europe, and the tropical pilot whale, which, as one would assume by its name, lives in the wamer waters of the north of Africa. Nevertheless, in the Spanish coasts there are individuals from both species. The spatial superimposition of the areas of distribution, the similitude between the two species and the fact that it is difficult to identify the species in some cases based only on their morphometric characteristics, have led to believe the existence of some sort of hybridization between the two species.
The techniques of genetic analysis allowed the researchers to unequivocally determine the species of the studied individual. Moreover, they confirmed the existence of a hybrid adult individual, born from the mating of a common pilot whale and a fertile hybrid individual, whose mother was a common pilot whale and its father a tropical one. This is the first time ever that the existence of a fertile hybrid of this two species is described genetically and, also for the first time, between two cetacean species.
The research by Laura Miralles proceeds for her to defend her Thesis next year. The second part of her work is focused on trying to explain the origin of the hybridization between the two species and its geographical location. The Thesis by Laura Miralles, directed by the Tenured Professor of Genetics Eva García Vázquez and funded by the Severo Ochoa Program of the Principality of Asturias, will wholly approach the creation of species in the marine environment under the title Papel de las barreras biogeográficas e historia evolutiva en la estructura poblacional actual de especies marinas cosmopolitas.
Authors of the article:Laura Miralles
Santiago Lens
Antonio Rodríguez-Folgar
Manuel Carrillo
Vidal Martín
Bjarni Mikkelsen
Eva Garcia Vázquez
