Neogene Aegean

I intend to add references and a few illustrations here as a webpage. The main theme will be aspects of the Aegean Mammals of the Miocene and the associated biogeography which I am reading up on and hope to gain an understanding of. As I have not got to grips with the features of website creation I am not sure how this will work out but am going to make a start.

 

Слева: алилепус украинский (Alilepus ucrainicus). Справа: вверху слева — соня (Glis sp.), посредине слева — мышь ориенталомис (Orientalomys similis), внизу слева — хомяк (Cricetinus cf. varians), вверху в центре — хомячок (Cricetulus), вверху справа — полёвка плиомис (Pliomys sp.), посредине справа — полёвка промимомис (Promimomys sp.), внизу справа — слепыш одесский.

Above, illustrations of Eurasian Neogene Mammals from the Russian ‘Age of Mammals.’ website. Left, the Lagomorph Alilepus. Right a selection of rodents, beautifully illustrated on one plate.

Alilepus is one of four Old World genera of the Archaeolaginae and Leporinae of the Late Miocene, the others are;- Hypolagus, Pliopentalagus and Trischizolagus.

Six species of Alilepus are given in the reference below. These animals in the Family Leporidae arrived in Eurasia from North America during the Miocene, crossing the Beringian Land Bridge and gradually radiating westwards.

Reference online;-

ČERMÁK, S., ANGELONE, C. & SINITSA, M.V. 2015. ‘New Late Miocene Alilepus (Lagomorpha, Mammalia) from Eastern Europe – a new light on the evolution of the earliest Old World Leporinae.’ Bulletin of Geosciences 90(2), 431–451(6 figures, 2 tables). Czech Geological Survey, Prague.

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The Dormice Gliridae

During the late Miocene in Turkey 6 genera of Gliridae are known;- Glirulus, Microdyromys, Miodyromys, Myomimus, Muscardinus and Ramys.

The study of dental microwear of Miocene fossil Gliridae from the middle Turolian site of Hayranli in Eastern Anatolia shows evidence of a mixed seasonal diet of insects, fruit, seeds and grasses in a warm, humid environment where the majority of species had an arboreal existence. Gliridae species diversity increased in Eurasia from 5 species in the late Oligocene to 60 species by the climatic optimum of the mid Miocene as they adapted to more diverse habitats and expanded ranges.

The biodiversity of the Gliridae declined with the advent of drier and more open environments from the mid Miocene. Large mammal assemblages from Greece to Afghanistan show that herbivores and omnivores had hypsodonty patterns in line with grassland and open deciduous woodland habitats. A further influence on the decline in Dormouse diversity was possibly due to the rise of the Muridae in Europe.

Notes taken from the superb Paper and maps and chart of the reference below;-

Reference

Kaya, Ferhat and Kaymakçı, Nuretdin. 2013. ‘Systematics and dental microwear of the late Miocene Gliridae (Rodentia, Mammalia) from Hayranlı, Anatolia: implications for paleoecology and paleobiodiversity.’ Palaeontologia Electronica Vol. 16, Issue 3.

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“Eomys BW” by Nobu Tamura – Own work. Licensed under CC BY 3.0 via Commons – https://commons.wikimedia.org/wiki/File:Eomys_BW.jpg#/media/File:Eomys_BW.jpg

Reference;- Daxner-Hock, G. & Hock, E. (2009) ‘New data on Eomyidae and Gliridae (Rodentia, Mammalia) from the Late Miocene of Austria.’ Ann. Naturhist. Mus. Wien. 111A.

The list of species below from the reference is from the Pannonian sites of Austria and I have marked those recorded from Greece in the work.

Eomyidae:

Keramidomys ermannorum nov. spec. GREECE (as cf karpathicus).

Keramidomys cf. pertesunatoi (Hartenberger, 1966)

Eomyops catalaunicus (Hartenberger, 1966) GREECE

Gliridae:

Muscardinus vallesiensis Hartenberger, 1966

Muscardinus hispanicus de Bruijn, 1966

Muscardinus pliocaenicus austriacus Bachmayer & Wilson, 1970 GREECE

Glirinae gen. et spec. indet.

Glis minor minor Kowalski, 1963 GREECE

Myoglis ucrainicus Nesin & Kowalski, 1997

Paraglirulus werenfelsi Engesser, 1972

Paraglirulus schultzi nov. spec.

Glirulus lissiensis Hugueney & Mein, 1965

Graphiurops austriacus Bachmayer & Wilson, 1980

Myomimus dehmi (de Bruijn, 1966) GREECE

Vasseuromys pannonicus (Kretzoi, 1978)

Towards the end of the Miocene the species diversity had declined and the authors note that  ‘..from Early Turolian faunas of Austria only 5 to 6 species are known. At that time, ground-dwelling (Myomimus dehmi, Vasseuromys pannonicus and Graphiurops austriacus) and forest-dwelling dormice (Muscardinus pliocaenicus austriacus, Glirulus lissiensis and Glis minor minor) were equal in species numbers, but the individual numbers of the ground-dwelling M. dehmi and V. pannonicus are significantly higher than of all other species. This shift towards a decrease of forest-dwellers and increase of ground-dwellers at the beginning of the Turolian reflects the change from predominating forested wetland environments to more open woodland and steppe-like environments,..’

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One way in which climate in Eurasia through the Miocene influenced the establishment and duration of mammal faunas was through changing patterns of rainfall, with oceanic weather maintaining wetter conditions in the west while eastern Eurasia experienced long periods of aridity. Large vegetarian mammals with hypsodont molars, extended forelimbs and reduced toes were adapted to more open savannah and steppe landscapes and their success was due to their co-evolution with an open grassland environment.

The Hipparion fauna represents the great extent of the grazing animal assemblages. The fauna is traditionally typified by the horse Hipparion and the vast scale of its’ migration in Eurasia. This subject has been extensively researched in Russia and North America as well as Europe.

Away from the ecozones of grasslands and thinly wooded savannah mixed and evergreen forest persisted and responded to tectonic influences involving uplands and changes to sea levels.

An aspect of the subject I enjoy discovering in on-line papers and articles is the frequent use of maps and also photographs and drawings of fossil mammal specimens. There is a fundamental beauty to the fossils and they convey a sense of ecological history. The complex and challenging discovery, study and interpretation of these remains by archaeologists brings science to life.

Barbara Stanley 'Impala Fighting' an award-winning picture

Barbara Stanley ‘Impala Fighting’ an award-winning picture

The early Miocene mammal record is of a preponderance of forest browsing mammal species compared to a smaller number of grazing species, and through the millions of years of this Period a change towards a majority or equal number of grazing species.

The steppe of the Paratethys comprised open grasslands with numerous herbaceous plants, although toxic plants were not widespread. Floral diversity was very high. Heavy grazing and trampling influenced the grassland habitat and cold as well as arid conditions.

In addition to the west-east gradient of moisture-aridity a north-south temperature gradient was also influential. These gradients combined to form sometimes rapid but otherwise slow-moving changes to the emerging Palaearctic during the Miocene.

Reference;- Fortelius, M. et al (2006) ‘Late Miocene and Pliocene large land mammals and climatic changes in Eurasia’ Palaeogeography, Palaeoclimatology, Palaeoecology 238.

Another issue has been the nature of the formation of Littoral environments and their spread following changes to distribution of sea and land surfaces owing to uplift, sea level change and other factors.

The littoral habitat itself is mobile. This is an important feature of animal and plant geography as some former sea floor and lakeside habitats today are significant terrestrial habitats. The saline steppe soilsand semi-deserts can often be the residue of former marine areas.

Ref. Gabunia & Chochieva (1981) ‘Co-evolution of the Hipparion fauna and vegetation in the Paratethys region’ Georgian Academy of Sciences.

Climatic areas of aridity moved along with assemblages of mammals of particular species and families. The pattern of distribution of fossils and other evidence reflects this but also the landform during the period in question. It is interesting to see the relationship between some genera recorded in Iberia and then in Greece and Turkey. For example, the ‘Pikermi fauna’ of Greece spread westwards under conditions of increased aridity.

During the Miocene the geography often shows a more linear and fragile east-west or latitudinal geography between the Tethys and Paratethys and this in combination with uplift will have influenced the dispersion and also isolation of mammal genera.

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