28 paolo squatriti
Mediterranean living (summer dormancy, specially-formed and -colored leaves with
sunken pores, vast and complex root systems) but there is enough discrepancy between
plant behavior and climate to suggest Mediterranean plants got to the area before the
arid-summer climate pattern did (Grove and Rackham, 2001: 45).
A little less regular than the summers, but also ineluctable, are other ecological
“disturbances” that stimulated Mediterranean vegetation’s morphology. Endemic
fires have given a competitive advantage to plants that burn poorly, resprout quickly
from resilient roots, or leave behind seeds that germinate after burnings (indeed,
annuals are unusually prevalent in Mediterranean communities) (Blondel et al., 2010:
171–172). Likewise characteristic of Mediterranean vegetation are adaptations to
herbivores’ browsing: spiny branches, odorous, strongly-flavored and furry leaves are
supposed to deter sheep, goats, cattle, and other ruminants.
None of these adaptations is unique to Mediterranean plants. In comparable
climatic conditions in central Chile, or southwest Australia, or the western Cape of
Africa, or even the Crimea, as Braudel knew (1972–3: 235), plants behave similarly
and look and smell quite like the Mediterranean’s. Presumably because both northern
hemisphere regions originated in the same prehistoric landmass, the similarities are
most pronounced between the Mediterranean and coastal California. The aromatic
Mediterranean maquis of holm and prickly oaks, strawberry trees, carobs, tree heather
(Erica arborea), juniper, rock rose, brooms, rosemary, and several other small annuals,
low shrubs, and bulbs, has imitators elsewhere.
Yet unlike the similar vegetative communities across the globe, the Mediterranean’s
vegetation is inhospitable: very seldom does a new “exotic” plant manage to break in
without human help. Charles Darwin teased his American correspondents about how
old-world plants, among them Mediterranean ones, had “thrashed” new-world ones
and colonized the Americas more efficiently than American plants had managed the
return journey (Beinart and Middleton, 2004: 6). Understanding such imbalances
was Alfred Crosby’s main concern in researching what he called the “Columbian
Exchange,” the gigantic migration of animals, plants, microbes, and people that took
place across the Atlantic Ocean after European sailing ships mastered the crossing,
and which patterned modern times (Crosby, 1972). Unlike Darwin, postcolonial peo-
ple doubt the global dominance after 1492 of old-world species, and it is true that
old-world plants did not all enjoy success: the eastern Mediterranean’s species, more
accustomed to aridity, have exported themselves far better than the western
Mediterranean’s (Beinart and Middleton, 2004; Groves, 1991, 436; Allen, 2009).
Still, the resistance of Mediterranean vegetative communities to imported “exotics”
remains one of their most striking features, with perhaps the steppes of North Africa
and western Asia most impervious (Le Floc’h, 1991: 71–73). Grove and Rackham,
the leading British investigators of Mediterranean flora in history, call this impenetra-
bility “mysterious” (2001: 46). Other botanists have sought the secret to the resilience
of Mediterranean vegetation in its exceptional biodiversity: in an area much smaller
than continental Europe’s, the Mediterranean has four times as many species of plants,
some 25 000 (Allen, 2009: 215; di Castri, 1990: 12–13; see also Delort and Walter,
2001: 155; Blondel et al., 2010: 268–271).
This phenomenal diversity is a consequence of the Mediterranean’s enclosure by
three major, botanically distinct landmasses and of low nutrient and biomass levels.
Abruptly varied terrain also favors botanical seclusion: the Greek and Balkan sections