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The island of Marettimo must have been part of a « South Tirrenic Continent » at the beginning of
the Miocene, and must have become an island at the beginning of the Quaternary period.

The South Tirrenic Continent consisted of three main portions (Fig. 154):

1. a paleogenic portion, corresponding to the cristallin mountains of Calabria and Sicily, which
acted as a bridgehead for the invasion of egean plants.
2. an oligocenic-miocenic portion corresponding to the calcareous west Sicily and therefore
including also Marettimo, which acted as a bridgehead for the invasion of the plants coming
from the Riffan-Betic lands and from Corsardinia and Algeria.
3. a pontic portion which extended from Sicily to the central italian peninsula.

Marettimo, owing to its position at the south western point of this South Tirrenic Continent is
particularly rich in western mediterranean relicts.

The colonisation of Marettimo took place most probably during the Miocene (Fig. 153). During the
greatest sea ingressions Marettimo probably became and island of an Archipelago, successively at
the time of the greatest land emersion Marettimo became once more part of the above mentioned
Continent, and took connection with the North Western lands.

During the Pontic the mountains of Marettimo probably were surrounded by a lagoon, somehow
like Monte Argentario today, in the Tuscan Maremma.

The survival of several peculiar species in Marettimo has been possible chiefly thanks to the
ecological-geographical conditions of the island.

Being a small island well isolated from the main land, Marettimo has a very even climate. The
underground circulation of waters is particular abundant and the fresh waters seeping from the
crevices weakens the effects of summer dryness. Finally the geographical isolation of Marettimo
probably dating from the Calabrian has prevented the ingression of a more recent flora. The land
bridges which could occasionally have risen during the glaciations probably have not been much
efficient in this respect.

The vegetation of Marettimo probably has not changed in its general outline since the time of its
isolation from the main land; this is shown also by the fact that its relict species are scattered in
different habitats and not only limited to typical refuge stations such as limestone cliffs. Exspecially
important in the preservation of the peculiarities of this vegetation must have been the isolation of
Marettimo during the interglacial periods.

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