Time-Distance Analysis
129
3.0.0 Species reported in the Canal after 1930, including mainly the species of
Gruvel and Moazzo, Lami, and the Hebrew University-Smithsonian Institution
collections.
4.0.0 Species not reported from the Suez Canal.
2. The second parameter, "emergence into the Mediterranean", is graded as
follows:
0.1.0 Species reported in the Mediterranean before 1929. This includes the
Cambridge Expedition reports, and the reports by Pallary, Gruvel, and W. Steinitz.
0.2.0 Species reported in the Mediterranean before 1955. This is the year
which according to Oren (1957) marked the beginning of an upward fluctuation in
the temperature ofthe Levant Basin.
0.3.0 Species reported in the Mediterranean after 1955.
3. The area occupied in the Mediterranean is graded into four categories,
according to a subdivision into provinces based on preliminary information:
0.0.1 Species confined to the area off Alexandria in the west and the Sinai coast
in the east. These are species which did not leave or could not settle beyond the
immediate vicinity ofthe Canal outlet.
0.0.2 Species which have advanced along the Levant coast and have been
reported along the shores of Israel, Lebanon, and Syria.
0.0.3 Species which have reached the area of Iskenderun and Mersin in the
eastern corner of Anatolia, and have advanced as far as Rhodes, or have been
reported from the islands of Cyprus and Crete.
0.0.4 Finally, a somewhat odd category-not a further gradation of the previous three-are the species which are known from the North African coast, west
of Alexandria, or from the Islands of Sicily, Malta, Lampedusa, etc., i.e. the
western confines ofthe Eastern Mediterranean.
Taking into account both the Suez Canal species and those not reported from
the Canal, there are 48 possible combinations. These are presented in a "checkerboard" diagram (Table 5) which also indicates the respective number of species.
The 3-digit symbol designating each species is also included in the two lists of
migrants (see Tables 2 and 3).
From the list of 204 migrants, only 193 species have been provided with such
symbols. The remaining 12 species have not been inc1uded in this analysis for
different obvious reasons. These are species which still have an uncertain status,
or represent a group exceptional from the ecological point of view.
A last point worth mentioning is that in the strictly chronological sense, the
2.0.0 species are contemporaneous with the 0.1.0 species and the 3.0.0 species with
the 0.2.0 and 0.3.0 species. The fact that only 1 species out of 119, the bivalve
Chama broderipi is a 3.1.0 species, i.e. a species reported from the Mediterranean
b40re being reported from the Suez Canal, is encouraging for the reliability of our
knowledge. In addition Chama is a 3.1.1 species, i.e. one which did not expand
beyond the immediate vicinity ofthe Canal outlet.
Ifwe apply the same to the 4.0.0 species, we shall find only five 4.1.0 species (vs.
31 4.2.0 and 38 4.3.0). Of these, two are algae: Caulerpa scalpelliformis which was
reported from the Mediterranean in 1930 (at the limit of 0.2.0!) and Hypnaea
nidifica, a species probably passively transported ; the sponge M ycale erythaeana
129
3.0.0 Species reported in the Canal after 1930, including mainly the species of
Gruvel and Moazzo, Lami, and the Hebrew University-Smithsonian Institution
collections.
4.0.0 Species not reported from the Suez Canal.
2. The second parameter, "emergence into the Mediterranean", is graded as
follows:
0.1.0 Species reported in the Mediterranean before 1929. This includes the
Cambridge Expedition reports, and the reports by Pallary, Gruvel, and W. Steinitz.
0.2.0 Species reported in the Mediterranean before 1955. This is the year
which according to Oren (1957) marked the beginning of an upward fluctuation in
the temperature ofthe Levant Basin.
0.3.0 Species reported in the Mediterranean after 1955.
3. The area occupied in the Mediterranean is graded into four categories,
according to a subdivision into provinces based on preliminary information:
0.0.1 Species confined to the area off Alexandria in the west and the Sinai coast
in the east. These are species which did not leave or could not settle beyond the
immediate vicinity ofthe Canal outlet.
0.0.2 Species which have advanced along the Levant coast and have been
reported along the shores of Israel, Lebanon, and Syria.
0.0.3 Species which have reached the area of Iskenderun and Mersin in the
eastern corner of Anatolia, and have advanced as far as Rhodes, or have been
reported from the islands of Cyprus and Crete.
0.0.4 Finally, a somewhat odd category-not a further gradation of the previous three-are the species which are known from the North African coast, west
of Alexandria, or from the Islands of Sicily, Malta, Lampedusa, etc., i.e. the
western confines ofthe Eastern Mediterranean.
Taking into account both the Suez Canal species and those not reported from
the Canal, there are 48 possible combinations. These are presented in a "checkerboard" diagram (Table 5) which also indicates the respective number of species.
The 3-digit symbol designating each species is also included in the two lists of
migrants (see Tables 2 and 3).
From the list of 204 migrants, only 193 species have been provided with such
symbols. The remaining 12 species have not been inc1uded in this analysis for
different obvious reasons. These are species which still have an uncertain status,
or represent a group exceptional from the ecological point of view.
A last point worth mentioning is that in the strictly chronological sense, the
2.0.0 species are contemporaneous with the 0.1.0 species and the 3.0.0 species with
the 0.2.0 and 0.3.0 species. The fact that only 1 species out of 119, the bivalve
Chama broderipi is a 3.1.0 species, i.e. a species reported from the Mediterranean
b40re being reported from the Suez Canal, is encouraging for the reliability of our
knowledge. In addition Chama is a 3.1.1 species, i.e. one which did not expand
beyond the immediate vicinity ofthe Canal outlet.
Ifwe apply the same to the 4.0.0 species, we shall find only five 4.1.0 species (vs.
31 4.2.0 and 38 4.3.0). Of these, two are algae: Caulerpa scalpelliformis which was
reported from the Mediterranean in 1930 (at the limit of 0.2.0!) and Hypnaea
nidifica, a species probably passively transported ; the sponge M ycale erythaeana