PhD Arthur Decae 2010 - Ghent Ecology - Universiteit Gent

Indian Ocean and the Strait of Gibraltar would open (probably periodically) to connect the
western Mediterranean with the Atlantic again. The western Mediterranean in this period was
a distinct sea from the eastern Mediterranean. Opening of the Strait of Sicily in time would
renew the connection between the eastern and western parts of the Mediterranean Basin. The
familiar geography of the region is now becoming visible although the major peninsulas and
archipelagos as well as the connection between the Black Sea (Bosporus – Dardanelle
connection) still had to develop (Fig. 4).
Fig. 4 Mediterranean in the early Miocene (approx. 20myBP). The western Mediterranean is separated
from the eastern Mediterranean, The Paratethyis is reduced to isolated basins and the European
Continent is taking its final shape. Source: R.Blakey.ucc.nau.edu/
Mediterranean Biodiversity
What is the connection between the above exposé on plate tectonics and the high biodiversity
in the Mediterranean The geological history sketched-out here shows that the Mediterranean
was formed at the crossroads of the African, Asian and European continents (Fig. 3). So, parts
of the native florae and faunae of these three continents are expected to have met and mixed
within the Mediterranean leading to an increase of species richness. Moreover one of the three
contributing continents, Europe, had existed as an extensive archipelago of larger and smaller
islands for many millions of years. In this archipelago the evolution of island endemics must
have been high and the contribution from Europe to the later Mediterranean flora and fauna
must have been particularly rich. This reasoning however only relates to terrestrial
biodiversity. The repeated opening and closing of seaways and the constant formation of
separate aquatic basins both in the Mediterranean and the Paratethys must have had further
effects of the enrichment on the marine flora and fauna of the Mediterranean. These basic
conditions for the development of a particularly rich biodiversity in the Mediterranean have
prevailed throughout the geological formation of the region to our present time. And there is
even more than the historical high diversity of terrestrial and marine biomes in the