Comparative genetics of scyphozoan species reveals the geological history and contemporary processes of the Mediterranean Sea. Issue 15 (8th July 2021)

• Record Type: Journal Article
• Authors: Mizrahi, Gur A.; Shemesh, Eli; Mizrachi, Avia; Tchernov, Dan
• Is Part Of: Ecology and evolution. Volume 11:Issue 15(2021)
• Page Start: 10303
• Page End: 10319
• Publication Date: 2021-07-08
• Subjects: clock tree -- invasive species -- jellyfish -- Lessepsian migration -- Mediterranean Sea -- Red Sea; Ecology -- Periodicals; Evolution -- Periodicals; 577.05
• DOI: 10.1002/ece3.7834
• Languages: English
• ISSNs: 2045-7758

Abstract

Abstract: Jellyfish are useful genetic indicators for aquatic ecosystems as they have limited mobility and are highly exposed to the water column. By using comparative genomics and the molecular clock (timetree) of Rhizostoma pulmo, we revealed a divergence point between the East and West Mediterranean Sea (MS) populations that occurred 4.59 million years ago (mya). It is suggested that the two distinct ecological environments we know today were formed at this time. We propose that before this divergence, the highly mixed Atlantic and Mediterranean waters led to the wide dispersal of different species including R . pulmo . At 4.59 mya, the Western and Eastern MS were formed, indicating the possibility of a dramatic environmental event. For the first time, we find that for the jellyfish we examined, the division of the MS in east and west is not at the Straits of Sicily as generally thought, but significantly to the east. Using genomics of the Aurelia species, we examined contemporary anthropogenic impacts with a focus on migration of scyphozoa across the Suez Canal (Lessepsian migration). Aurelia sp. is among the few scyphozoa we find in both the MS and the Red Sea, but our DNA analysis revealed that the Red Sea Aurelia sp. did not migrate or mix with MS species. Phyllorhiza punctata results showed that this species was only recently introduced to the MS as a result of anthropogenic transportation activity, such as ballast water discharge, and revealed a migration vector from Australia to the MS. Our findings demonstrate that jellyfish genomes can be used as a phylogeographic molecular tool to trace past events across large temporal scales and reveal invasive species introduction due to human activity. Abstract : With the use of genetic tools, we revealed a divergence point between the East and West Mediterranean Sea populations that occurred 4.59 million years ago, and we propose that the western and eastern Mediterranean Sea were formed at that time. For the first time, we find that the division of the Mediterranean Sea in east and west is not at the Strait of Sicily, but significantly to the east. Aurelia sp. DNA analysis revealed that the Red Sea Aurelia sp. did not migrate or mix with Mediterranean Sea species. Phyllorhiza punctata results showed that this species was only recently introduced to the Mediterranean Sea from Australia due to human activity.