| Abstract |
A characteristic endemic fauna, restricted to the island of Crete occurred
during the Middle and Late Pleistocene, consisting of cervids, small sized elephants,
dwarf hippos and mammoths, giant murids, shrews, birds and reptiles but almost
lacking carnivores (only a lutrinid has been discovered). This rather unbalanced
fauna, typical for oceanic and oceanic-like islands, is related with the tectonic
processes that led to the final configuration of Crete in the early Pleistocene. It
evolved as only a few vertebrate groups, capable for migration via open sea,
colonized the virgin island and underwent genetic changes after their forced
settlement in terms of ‘sweepstake dispersal’, adapting to the insular isolated
environment. Examples of insular evolution can also be found in the fossil record of
other islands of the Greek archipelago and the Mediterranean basin.
In the endemic mammal fauna of Crete, the ungulates were by far the most
successful forms during Late Pleistocene (0.3-0.01 Mya). Cervid fossils have been
known since the end of 19th century and different taxonomic units have been
described based on the dental, cranial, post-cranial and antler morphology of the
remains. The Cretan deer has been represented by several morphotypes ranging from
dwarf to relatively gigantic size, which adapted to different habitats and probably
occupied different ecological niches.
However, the strong endemism, induced by insularity, the overall higher
diversity than on mainland and the poor stratigraphic record make their taxonomy,
ancestry and evolutionary history rather problematic. Different hypotheses concerning
the phylogenetic and systematic relationship of the Cretan cervids have emerged. All
these taxa belonged either to one genus (Candiacervus) on the basis of monofyly or to
more implying different ancestors. Two other endemic Pleistocene cervids, with size
resembling that of the dwarf Cretan forms, have been mentioned from the nearby
island of Karpathos since the early seventies. The smaller species was defined as
Candiacervus cerigensis while a larger species named C. pygadiensis was recognized
from different antler morphology.
In the present study, the biometrical analysis of size variation and limb
morphology of the Cretan deer and comparison with Karpathos findings were
attempted. The studied fossil material, currently stored in the Natural History
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Museum of Crete, was originally collected from numerous cave localities in the late
sixties and early seventies by the German palaeontologist S.E. Kuss, and is part of the
so called Kuss collection formely housed in the Natural History Museum of
Karlsruhe. Part of the material (localities Liko B, C, D, Simonelli) belongs to the
collection of Museum of Paleontology and Geology of University of Athens. Various
measurements were taken on the three basic segments of fore- (humerus, radius,
metacarpal) and hindlimb (femur, tibia, metatarsal) skeleton with the aid of digital
calipers to the nearest 0.01 mm. Only data from recognizably full grown bones (as it
was indicated by the fusion of epiphyses to the diaphysis) were used in the analysis.
The two smallest size groups (size 1 and 2) and partly the mid-sized
morphotype (size 3) of De Vos classification were distinguished in the material from
Crete as scatter plots of combinations of several measurements on full grown bones
have shown. The most typical forms are the dwarfed species being widely spread and
abundant while the larger sizes are extremely rare. These likely last representatives of
the Cretan deer had short and massive limbs displaying a much greater degree of
robustness that continental cervids and probably occupied a niche similar to that of
the wild goat of Crete today. The best candidate ancestor seems some megacerine
mainland species, which colonized Crete in the early Middle Pleistocene. On the other
hand, the evolutionary history of larger forms is rather controversial. Despite
insufficient evidence, they might have derived from a different large cervid, whose
arrival followed that of the megacerine deer.
Furthermore, multivariate analysis (PCA) resulted in a definite morphological
distinction between the post-cranial material from the two islands. The Karpathos
endemic cervids Karpathos endemic Pleistocene deer material forms two size classes
indicating generally resembling that of the two smallest Cretan sizes respectively but
differ significantly from the deer remains found on Crete, bearing unique anatomical
features, and implying no direct link with the Cretan stock. Therefore, the original
deer genus determination is certainly under question with some Asian mainland
species appearing the most suitable ancestor. However, the existence of two different
species in Pleistocene Karpathos, as Kuss originally concluded, is also suggested.
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Βιομετρική μελέτη του μετακρανιακού υλικού των Πλειστοκαινικών ελαφιών της Κρήτης και της Καρπάθου
