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M. Masseti: Homogenisation and the loss of biodiversity of mammals of the Mediterranean islands 189
in view of the high proportion of endemic species and
the specific biogeographical situation linked to their iso-
lation (Lowe et al. 2000, Clout 2002, Genovesi 2002,
2005, Gippoliti and Amori 2002, Masseti 2002d,e, Wit-
tenberg 2002, Courchamp et al. 2003, Pascal et al. 2006).
The most significant cases of biodiversity loss are effec-
tively to be found on the islands, where we have seen
indigenous species have often evolved in the absence of
strong trophic competition, parasitism or predation (Mas-
seti 2002d,e). As a result, the introduced species also
thrive in the optimal insular ecosystems that affect their
plant food, competitors or animal prey. It is above all on
islands that the biological records offer univocal evidence
of the appearance of allochthonous species and anthro-
pogenic introductions. The fact is that on the islands the
impact of extraneous elements on the unspoilt ecological
system can be identified and its chronology specified
with considerable precision, as a result of the evidence
left and the relative rapidity of the consequences pro-
duced (Masseti and Vianello 1991).
Invasive mammals have caused the majority of the
insular extinctions over the past thousand years (Atkin-
son 1989, Groombridge 1992, Howald et al. 2007). To
alleviate the impact of such invasions for the sake of con-
servation, eradication of the alien species appears to be
crucial (Genovesi 2005).
A weighty legacy
As pithily expressed by de Planhol (2004) in his book ‘‘Le
paysage animal. L’homme et la grande faune: une zoo-
ge´ ographie historique’’: ‘‘«man, a superior predator, was
destined to devastate and destroy. And he did.’’ However,
expounding an analysis rich in quantitative clarifications,
the author goes on to argue that this phase is by now
over and behind us: ‘‘For at least the last fifty years,
humanity has shifted from the destruction stage to that
of protection, even of resurrection, already recording bril- the biological and ecological characteristics of their wild
liant successes, the number of which is bound to
increase.’’ Nevertheless, the legacy of the global redefi-
nition of the original ecological equilibrium of the Medi-
terranean islands raises not inconsiderable problems of
conservation and management. First of all, in the vast
majority of cases, it is impossible to reconstruct the nat-
ural ecosystems of the past which have been irretrievably
destroyed, lost thousands of years ago (Masseti
2002b,d).
In view of the vulnerability of the insular ecosystems,
it is also critically important to prevent further introduc-
tions. From both a scientific and a cultural point of view,
it would be advisable to seriously take into consideration
the eradication of the alien species of very recent inva-
sion, such as, e.g., Myocastor coypus Molina 1782, in
Sicily and/or Mustela vison Schreber 1777, in Sardinia.
But this results in the question of how to treat the allo-
chthonous populations of certified ancient anthropocho-
rous origin (Masseti 2002b, 2002d, 2007d). Each of such
cases has to be considered individually. If, in fact, the
eradication of rats, rabbits and feral goats imported in
recent historical times is in many cases fundamental for
the recovery of island ecosystems, several of the other
anthropochorous taxa represent invaluable historic doc-
uments, images which remain fixed in time and history.
For instance, this would be the case of the martens of
Elba (Figure 23), the genets of the Balearics, the red deer
of Sardinia and Corsica, the mouflons of Cyprus and of
the largest Tyrrhenian islands, the wild goats of Monte-
cristo or Antimilos, and many other extant insular popu-
lations of mammals (Table 4; Figure 24).
Unlike the case of artistic monuments, however, here
we are dealing with living organisms which interact with
environments originally extraneous to their natural distri-
bution, but which they have inhabited since ancient
times. Their protection and their study can provide an
opportunity for testing a range of different evolutionary
theories. While the importance of these anthropochorous
populations is not comparable, from a biological point of
view, to that of veritable wild populations in their natural
habitat, their elevated validity as environmental entities
lies in their representing singular historical and cultural
documents (Masseti 2002b). The exclusion of known
anthropochorous taxa from conservation lists, followed
by implementation of ulterior protective legislation, has
been proposed as a necessary measure to maintain the
uniqueness and richness of Mediterranean biodiversity
(Gippoliti and Amori 2004, 2006). Nevertheless, an
excessively philological and ‘‘purist’’ approach to the
compilation of the conservation documents may even
prove to be detrimental, as we have seen that the prim-
eval ecosystems of the Mediterranean islands were irre-
trievably lost thousands of years ago. In the more
specific case of the endemic mammals, they are practi-
cally entirely extinct.
Nor should we overlook the fact that many of these
anthropochorous populations, which have inhabited the
islands since immemorial time, constitute some of the
few available points of reference for an understanding of
continental ancestors, by now long extinct. Consequently
they deserve to be protected and considered in terms of
a veritable ‘‘cultural heritage’’. Just as human artefacts
and sites of archaeological and historical interest are
subject to conservation strategies, we must thus also
protect the populations of animals of ancient anthropo-
Figure 23 The extant occurrence of the pine marten, Martes
martes L. 1758, on the island of Elba (Tuscan archipelago,
Northern Tyrrhenian Sea, Italy) is assumed to be of ancient
anthropochorous origin (photo: Marco Masseti).