EXECUTIVE SUMMARY - UNESCO World Heritage

2.b History and
Development
A single tree species – the beech – having
come to dominate the forest and ecosystemary
development of major portions of an
entire continent over the course of an
ongoing ecological process is unparalleled
globally. Th is dominance has developed
within a few thousand years after the last ice
age – which is extremely short a period
from a geological or evolutionary perspective.
Within Europe, the ongoing process
currently shows particularly strikingly in
Germany.
Processes of Europe’s
evolutionary development
Although the Gondwana supercontinent
had started to fragment at the turning
point from Triassic to Jurassic, the fragments
were initially close to each other so that
plants could spread. A number of recent
plant taxa therefore have a distinct “Gondwana
distribution range”. Relic areas on the
southern tip of South America, Australia,
and New Zealand are possibly occupied
by the southern beech (Nothofagus) genus
(WALTER & STRAKA 1970). Nothofagus
might have evolved within the region
of what is Antarctica today, but was subsequently
unable to reach the portions
of Gondwanaland that had detached already
at an earlier point (Africa, Madagascar,
India). However, it would come to South
America, New Zealand, and Australia, where
it has persevered ever since (CRANWELL
1963, 1964 in WALTER & STRAKA
1970). Disjunctive distribution might best
be explained by the existence of a former
antarctic land bridge (DU RIETZ 1940,
quoted in WALTER & STRAKA 1970).
It is assumed that Fagus spread from a
“warmer subterritory of Laurasia”. Th e bipolar
areas of the nearest related genuses
Nothofagus and Fagus are most probably due
to migrations across the tropical high
mountains. Until the Eocene, the Central
European fl ora was showing a tropicalsubtropical
character (Arctotertiary fl ora,
WALTER & STRAKA 1970). By the
end of the Oligocene, it was losing species
under the infl uence of a temperate climate.
Deciduous forests had developed as early
as during the period when broad-leaf in decid
u ous species migrated from tropical to
more temperate zones. Th is adaptation would
allow them to survive in the northern
hemisphere in the cool to chill climate of the
Miocene, while the austral woodland vegetation
in the southern hemisphere has
been dominated by broad-leaf indeciduous
forest to the present day. Th e Central
European Miocene fl ora saw the blending
of numerous geographical elements (East
Asian, North American, Mediterranean,
Subtropical, Tropical, Holarctic, and Eurasian).
During this epoch, a beech species
appeared being an intermediate type between
the North American Fagus grandifl ora
and the European Fagus sylvatica (WALTER
& STRAKA 1970).
Th e subsequent loss of species in Europe
resulted from climatic changes. By the end
of the Pliocene epoch, the Quarternary
was already about to set in with its relatively
rapid and strong variations in temperature.
Th e Glacial epoch (Pleistocene) with at
least four glacials had commenced, causing
the tropical-subtropical and East Asian-
North American elements to disappear.
Yet it was not before the onset of the Middle
Pleistocene that the temperate fl ora would
turn into what we see today (fi g. 2.14, 2.15).
2. DESCRIPTION
The German beech forests
represent the development
process which has
been taking place in
Europe since the Ice Age.
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