Геологическая история и фауногенез Казахстана и сопредельных территорий в эпохи развития млекопитающих и антофильных насекомых

dominated. For ground vertebrates fauna of bottom cretaceous, as well as for jurassic, the abundance of
reptiles is characteristic. The second half of the cretaceous period is characterized by extinction of the
majority of reptiles and a[ppearance of small mammals, which later - in the tertiary period – have
become prevailing groups together with birds. As for the fauna of insects in Eurasia, in early cretaceous
differed from jurassic fauna a little. The most significant events were appearance and development of
phytophagous insects connected with angiospermous plants, and also predatory and parasitic
hymenopterous insects - pollinators (Hymenopterea, butterflies, flies, etc.). Appearance and the active
development at the last has resulted in the blowing of flowering plants, pollinated by insects. 
In the beginning of the tertiary period all continents of the southern hemisphere had already lost
connection with each other. As to the continents of the northern hemisphere, all of them in the
paleocene were connected with each other by sites of a land, so-called “bridges”. In some cases these
“bridges” temporarily connected the continents, as Turgay or Pireney ones, in the others they unitied
continents together for a very long period of time, as Beringia and Greenland, or North-Atlantic. With
formation of Turgay isthmus the West-Sibirian sea was separated from the Tethys, which occupied
territory of Kysylkum and Karakum and reached low hills of western Tien-Shan. Pamir and Tien-Shan
represented low hilly land. The similar hilly landscape existed in the northeast part of Kazakhstan. The
climate in paleocene was considerably warmer, damper and more monotonous in comparison with the
existing one. Warm waters of the Tethys created monsoonic climate, damp enough by the coasts and a
little more continental further from them. The most part of territory of northern Asia was occupied by
so-called “turgay”, moderate-subtropical flora, only its southern part (in particular, Central Asia) was
occupied by tropical and subtropical flora of oriental type such as - “Poltava” flora. The beginning of
paleogene is characterized by an output of mammals on one of the first places among an animal
population of the Earth and their wide distribution. As to insects fauna, it has already got basic features
of modern fauna at a level of families. 
In eocene the Asian continent’s outlines were almost the same, as in paleocene. After complete
isolation in the middle eocene some connection with Northern America and with Europe has appeared.
The most part of territory of Kazakhstan and Central Asia still was filled with the sea. It cut into Kazakh 
upland, Tien-Shan and other mountain systems by numerous gulfs. In late eocene as the Alpine
orogenesis has started the retreat and shallowing of the sea in some mountain areas have taken place.
Turgay strait periodically turned into land, but then reappeared in connection with new transgressions
of the sea. The climate within the limits of Central Asia and Kazakhstan in the vicinity of coasts was
monsoonic, hot and damp, but became more continental and droughty on the distant from the sea low
mountains lands and hilly plains. Aridisation began to amplify in the second half of eocene. The most
part of territory of Central Asia and Kazakhstan was occupied by turgay flora, only in the south of
Central Asia there was poltava flora of oriental type. With gradual aridisation of a climate the areas
occupied by flora of xerophytous type have increased. As a result of aridisation the open territories with
rarefied wood vegetation and bushes appeared. The development of fauna in eocene went on isolated,
though the connection with Europe by Turgay bridge and with America by Beringia bridge was
established from time to time. Fauna as a whole was composite and alongside with archaic forms had a
number of new ones. The change of the foliavorous forms of mammals by the herbivorous ones took
place.
In oligocene all continents were already detached, though some of them were connected with each
other by “bridges”. The low territory of Central Asia and Kazakhstan was occupied by the sea. All
intermountain valleys were gulfs of the sea. The ancient ranges of Тien-Shan, hilly country of Kazakh
upland, Turkestan’s and Hissar’s mountain ranges, separate lotly places inside Kyzylkum and Karakum
remained dry land. Orogenetic processes have resulted in amplification of partition of territory and
erosive activity. Drop in temperature began to distribute from the north on the Asian continent in
oligocene, the contrast of summer and winter temperatures grew, aridisation of Central Asia, Middle
Asia and Kazakhstan amplified. The climate became more differential and continental. Vast grassy areas 
have begun to form on the basis of new groups angiospermous plants, first of all of cereals in oligocene.
In Kazakhstan there was a change of the poltava subtropical elements by turgay ones, in Central Asia
and in the south of Kazakhstan the vegetation of droughty type has appeared. The amount of
vertebrates - inhabitants of open spaces has increased. The changes in the world of insects were
connected mainly with the settling of grassy communities, in which there was an intense evolution of
phitophagous insects as well as their predators and parasites. 
In neogene all the continents have already got the outlines close to modern ones. On Eurasian
continent orogenesis has amplified, at the same time the area of sea pools was reduced to great extent.
On the territory of Kazakhstan and Central Asia the sea disposed in Kaspian lowland and included the
Aral sea. In connection with the regression of the Tethys and raising of mountain systems the
continental character of a climate has substantially increased. The total drop in temperature and drying
went on. In Central Asia and Southern Kazakhstan the deserts and semideserts were formed. In
miocene an almost total replacement of the Poltava elements by turgay ones and the development of
xerophilous vegetation took place. The establishment of connection between Eurasia and Africa
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