Candiacervus
Encyclopedia
Candiacervus was a genus of deer native to Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

 Crete. Their most notable feature, besides their peculiar, spatula-shaped antlers, was their small stature: the smallest species, C. ropalophorus, stood about 40 cm at the shoulders when fully grown, as can be inferred from a mounted skeleton. As such, the genus is considered to be a textbook example of insular dwarfism
Insular dwarfism
Insular dwarfism, a form of phyletic dwarfism, is the process and condition of the reduction in size of large animals – typically mammals – when their population's range is limited to a small environment, primarily islands. This natural process is distinct from the intentional creation of dwarf...

. Other features are the relatively short limbs, the massivity of the bones and the simplified antler.

Ironically, they were closely related to the giant Irish Elk
Irish Elk
The Irish Elk or Giant Deer , was a species of Megaloceros and one of the largest deer that ever lived. Its range extended across Eurasia, from Ireland to east of Lake Baikal, during the Late Pleistocene. The latest known remains of the species have been carbon dated to about 7,700 years ago...

, with some experts regarding Candiacervus as a subgenus
Subgenus
In biology, a subgenus is a taxonomic rank directly below genus.In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic name and the specific epithet: e.g. the Tiger Cowry of the Indo-Pacific, Cypraea tigris Linnaeus, which...

 of Megaloceros
Megaloceros
The deer of the genus Megaloceros - ; see also Lister - were found throughout Eurasia from the late Pliocene to the Late Pleistocene, and were important herbivores during the Ice Ages. The largest species, M...

.

Large variation

The Cretan deer is represented by no less than eight different morphotypes, ranging from dwarf size with withers
Withers
The withers is the ridge between the shoulder blades of a four-legged animal. In many species it is the tallest point of the body, and in horses and dogs it is the standard place to measure the animal's height .-Horses:The withers in horses are formed by the dorsal spinal processes of roughly the...

 height of about 40 cm to very large with withers height of about 165 cm. This is explained as a sympatric speciation
Sympatric speciation
Sympatric speciation is the process through which new species evolve from a single ancestral species while inhabiting the same geographic region. In evolutionary biology and biogeography, sympatric and sympatry are terms referring to organisms whose ranges overlap or are even identical, so that...

 to occupy all possible empty niches ranging from dense forest to prickly rocks. The coexistence of various environments has been confirmed by studies on the rich fossil avifauna
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

. The most typical Cretan deer are the two smallest sizes, which have not only relatively and absolutely short limbs, but also long and simplified antlers; these species occupied a niche close to that of the wild goat of Crete today: barren rocks with thorny bushes, as shown by features of their osteology and goat-like body proportions. It deviated so much from mainland deer that it is impossible to indicate with certainty its ancestor. Suggested ancestors are Cervus peloponnesiacus and Megaloceros
Megaloceros
The deer of the genus Megaloceros - ; see also Lister - were found throughout Eurasia from the late Pliocene to the Late Pleistocene, and were important herbivores during the Ice Ages. The largest species, M...

 verticornis
.

Taxonomical problems

The Cretan deer is a typical example of taxonomical problems involving endemic insular mammals, due to the much larger variety than on the mainland, and the strong endemism. This obscures taxonomy, because many endemic features of Candiacervus are not unique but are found in other island deer as well, such as Cervus astylodon (Ryukyu Islands) and Hoplitomeryx (Southern Italy).
De Vos, includes the eight morphotypes into one genus (Candiacervus), whereas Capasso Barbato does not follow this opinion of monophyly
Monophyly
In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it contains all the descendants of the possibly hypothetical closest common ancestor of the members of the group. The term is synonymous with the uncommon term holophyly...

, and included the larger species, rethymnensis, major and dorothensis, in Cervus (subgenus Leptocervus) and the smaller species ropalophorus and cretensis in Megaloceros (subgenus Candiacervus), which implies two different ancestors. She also does not recognize sp. II with its three morphotypes, and synonymises them with ropalophorus. At present these two views cannot be properly proven or discarded, but what stays is that the number of deer species is higher than on the mainland, and that they all occupy a different ecological niche.

Extinction of Candiacervus

From the late Middle Pleisocene till the arrival of humans in the Holocene, Crete was inhabited by small elephants, eight types of Cretan deer and a normal sized mouse. The cause of the dramatic faunal turnover, which led to the extinction of the endemic deer and elephants, may simply have been the arrival of paleolithic
Paleolithic
The Paleolithic Age, Era or Period, is a prehistoric period of human history distinguished by the development of the most primitive stone tools discovered , and covers roughly 99% of human technological prehistory...

 humans. They could have exterminated the deer either actively by hunting, or passively by destroying its habitat. Another option is a gradual depletion of the ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....

, as indicated by the finding of a complete herd consisting of individuals suffering a bone disease of an osteosclerotic
Osteosclerosis
Osteosclerosis, an elevation in bone density, is normally detected on an X-ray as an area of whiteness, and is where the bone density has significantly increased...

 nature (see X-ray photograph). The impact of paleolithic humans is at present still unproven, partly because of the scarcity on published fauna lists from archaeological sites (except for Knossos), partly because of the insecurely dated materials

Fauna with Candiacervus

The fauna of which Candiacervus is an element, is called Biozone II, or the Mus Zone (after the common mouse). This fauna inhabited Crete between the late Middle and Late Pleistocene, which means between 0.3 and 0.01 million years ago.

The typical fauna elements of this biozone
Biozone
Biostratigraphic units or Biozones are intervals of geological strata that are defined on the basis of their characteristic fossil taxa....

 are the common mouse (Mus bateae, M. minotaurus), the dwarf elephant (Elephas antiquus creutzburgi), the Cretan deer (Candiacervus, with the eight species ropalophorus, sp. IIa, b and c, cretensis, rethymnensis, dorothensis and major), the Cretan otter (Lutrogale (Isolalutra) cretensis), and the Cretan shrew
Shrew
A shrew or shrew mouse is a small molelike mammal classified in the order Soricomorpha. True shrews are also not to be confused with West Indies shrews, treeshrews, otter shrews, or elephant shrews, which belong to different families or orders.Although its external appearance is generally that of...

 (Crocidura zimmermanni).
The common mouse is represented by two species, of which the earlier is M. bateae, which is slightly smaller than the later M. minotaurus, and slightly larger than the common house mouse (Mus musculus). The two species belong to a single lineage with a long term trend for increasing size is attested. The Cretan shrew is one of the rare exceptions to the general rule that mammals change radically on islands. On most islands, the microfauna
Microfauna
Microfauna refers to microscopic organisms that exhibit animal-like qualities. Microfauna are represented in the animal kingdom and the protist kingdom...

 show the tendency to become large, as is the case of the Cretan mouse of the previous biozone. It is as yet not clear why this did not apply to the Cretan shrew. The Cretan shrew was obviously successful, and was not wiped out during the next faunal turnover, and managed to survive on Crete till the present day. The dwarf elephant may be large compared to the mammoth of the previous period, but it is still about 30% smaller than its mainland ancestor E. antiquus, which has a shoulder height of 3.7 m. The dwarf elephant has strongly curved tusks. It is still a matter of debate why this elephant did not reach a true pygmy size.

The Cretan otter is the only carnivore known from the Pleistocene of Crete. Its remains are known from only one locality (Liko Cave), and only in the upper layer thereof (Late Pleistocene). The Cretan otter was less aquatic in life style than the common otter (Lutra lutra) and the smooth otter Lutrogale perspicillata; this is considered a secondary development due to the special conditions on Crete. At first view it may seem strange that the Cretan otter did not develop towards gigantism as in rodents or towards dwarfism as in herbivores, though it seems that it is slightly larger than its mainland ancestor. However, this gigantism and dwarfism is caused by common factors as the absence of predators and limited food resources; for otters these factors are not relevant.

Karpathos

On the nearby island of Karpathos
Karpathos
Karpathos is the second largest of the Greek Dodecanese islands, in the southeastern Aegean Sea. Together with the neighboring smaller Saria Island it forms the municipality Karpathos, which is part of the Karpathos peripheral unit. From its remote position Karpathos has preserved many...

, Kuss found deer which were, in his view, similar to the Cretan deer. Therefore, he grouped his species pygadiensis and cerigensis under the genus Candiacervus, but this needs further confirmation. As long as no direct link with Crete is attested, the deer genus of Karpathos is questioned, and better referred to as Cervus.

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