Conspectus
1. "Lessepsian Migration"
The reader should first be introduced to the te:r:m "Lessepsian migration",
which is as yet of only limited circulation. The term was coined (Por, 1969 a,
1971 b) when it became evident that the unidirectional migration of the Red Sea
species to the Mediterranean via the Suez Canal is a unique phenomenon in
modem biogeography. This uniqueness in the dimensions and directionality of
the migration through the Suez Canal needed a short and diagnostic name. As
such, "Lessepsian migration" is a phenomenon of unidirectional and successful
biotic advance from the Red Sea to the Eastem Mediterranean. It does not
inc1ude migrational happenings which occurred through passive transport to
harbors far from the Canal; nor does it inc1ude the rather isolated cases of
migration in the opposite sense: from the Mediterranean to the Red Sea. Finally,
it does not inc1ude the many cases of migration into the Canal, though many of
such species might be future Lessepsian migrants.
2. The Structure of the Book
Even with the limitations of the term "Lessepsian migration" as given above,
the subject has to be treated in a fairly wide perspective: some biogeographic
aspects have to be c1arified and the geological history of the faunal divide between
the Mediterranean and the Indian Ocean has to be dealt with. Not only the
marine coastal environments and the Suez Canal itself, but also the Levant Basin
of the Mediterranean must be presented as the stage upon which the migrational
happening is taking place; this inc1udes some lagoon environments which serve as
terms of comparison.
The book is subdivided into three main sections: the first deals with the
geological-historical background, the second with the Suez Canal itself, and the
third with the Lessepsian migrants in their new environment in the Mediterranean. Two fmal chapters deal with the cases of contrary migration ("antiLessepsian migration"), and a comparison with other inter-oceanic canals and
biotic exchanges.
1. "Lessepsian Migration"
The reader should first be introduced to the te:r:m "Lessepsian migration",
which is as yet of only limited circulation. The term was coined (Por, 1969 a,
1971 b) when it became evident that the unidirectional migration of the Red Sea
species to the Mediterranean via the Suez Canal is a unique phenomenon in
modem biogeography. This uniqueness in the dimensions and directionality of
the migration through the Suez Canal needed a short and diagnostic name. As
such, "Lessepsian migration" is a phenomenon of unidirectional and successful
biotic advance from the Red Sea to the Eastem Mediterranean. It does not
inc1ude migrational happenings which occurred through passive transport to
harbors far from the Canal; nor does it inc1ude the rather isolated cases of
migration in the opposite sense: from the Mediterranean to the Red Sea. Finally,
it does not inc1ude the many cases of migration into the Canal, though many of
such species might be future Lessepsian migrants.
2. The Structure of the Book
Even with the limitations of the term "Lessepsian migration" as given above,
the subject has to be treated in a fairly wide perspective: some biogeographic
aspects have to be c1arified and the geological history of the faunal divide between
the Mediterranean and the Indian Ocean has to be dealt with. Not only the
marine coastal environments and the Suez Canal itself, but also the Levant Basin
of the Mediterranean must be presented as the stage upon which the migrational
happening is taking place; this inc1udes some lagoon environments which serve as
terms of comparison.
The book is subdivided into three main sections: the first deals with the
geological-historical background, the second with the Suez Canal itself, and the
third with the Lessepsian migrants in their new environment in the Mediterranean. Two fmal chapters deal with the cases of contrary migration ("antiLessepsian migration"), and a comparison with other inter-oceanic canals and
biotic exchanges.