Marine life is perceived as being more connected with one another, as opposed to land-based animals which can be segregated by barriers like mountains or motorways. However, a new study has uncovered evidence suggesting otherwise.
After studying two species of corals (pink sea fan and dead man's fingers), researchers at the University of Exeter have discovered distinct genetic differences within those living in different locations.
“Marine life is often seen as totally connected, in the sense that the larvae of any organism can move anywhere,” said Dr Jamie Stevens, Associate Professor of Molecular Systematics at the University.
“But among pink sea fans we have found genetic differences between those living off north-west Ireland, those off southern Portugal and those off south-west Britain and north-west France. These populations of pink sea fans are on the way to becoming different species from one another,” he added.
This may be caused by currents, which can prove to be as impenetrable as physical barriers.
In contrast, the other coral species – dead man's fingers – did not display any distinct genetic structures in different locations.
In addition, the populations of pink sea fans around southwest Britain turned out to be emitting more genetic material to other areas than their area receives.
The reasons for these differences have yet to be determined. However, the study may have implications for the planning and development of Marine Protected Areas (MPAs).
Although the existing MPAs in British waters appear to be well placed, Dr Stevens said, “If we want to safeguard the full range of diversity of marine species, we need to protect each species in multiple locations. For example, if we protect pink sea fans only off the coasts of the UK and France, we wouldn't be protecting the genetically different pink sea fans off Ireland or Portugal.”