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85-664: The sands of the deserts are the result of the weathering of Paleogene rocks; only the northern section of the Greater Barsuki was formed from more recent alluvial deposits . The Barsuki are roughly aligned in a SSW - NNE direction. They are located at the southern end of the Turgay Depression , stretching from the northern coast of the Aral Sea in the Kyzylorda Region to the southeastern sector of

170-737: A divergent to convergent plate boundary. The Alpine Orogeny developed in response to the collision between the African and Eurasian plates during the closing of the Neotethys Ocean and the opening of the Central Atlantic Ocean. The result was a series of arcuate mountain ranges, from the Tell - Rif - Betic cordillera in the western Mediterranean through the Alps , Carpathians , Apennines , Dinarides and Hellenides to

255-523: A natural reservoir of many pathogens , such as rabies ; and since they are highly mobile, social, and long-lived, they can readily spread disease among themselves. If humans interact with bats, these traits become potentially dangerous to humans. Some bats are also predators of mosquitoes , suppressing the transmission of mosquito-borne diseases . Depending on the culture, bats may be symbolically associated with positive traits, such as protection from certain diseases or risks, rebirth, or long life, but in

340-973: A 2005 DNA study. A 2013 phylogenomic study supported the two new proposed suborders. Yangochiroptera (as above) [REDACTED] Pteropodidae (megabats) [REDACTED] Megadermatidae (false vampire bats) [REDACTED] horseshoe bats and allies [REDACTED] The 2003 discovery of an early fossil bat from the 52-million-year-old Green River Formation , Onychonycteris finneyi , indicates that flight evolved before echolocative abilities. Onychonycteris had claws on all five of its fingers, whereas modern bats have at most two claws on two digits of each hand. It also had longer hind legs and shorter forearms, similar to climbing mammals that hang under branches, such as sloths and gibbons . This palm-sized bat had short, broad wings, suggesting that it could not fly as fast or as far as later bat species. Instead of flapping its wings continuously while flying, Onychonycteris probably alternated between flaps and glides in

425-552: A proliferation of aquatic ferns from the genus Azolla , resulting in the sequestering of large amounts of CO 2 from the atmosphere by the plants. From this time until about 34 Ma, there was a slow cooling trend known as the Middle-Late Eocene Cooling. As temperatures dropped at high latitudes the presence of cold water diatoms suggests sea ice was able to form in winter in the Arctic Ocean, and by

510-531: A rapid surge of diversification in the early Paleogene, as survivors of the Cretaceous–Paleogene extinction event took advantage of empty ecological niches left behind by the extinction of the non-avian dinosaurs, pterosaurs, marine reptiles, and primitive fish groups. Mammals continued to diversify from relatively small, simple forms into a highly diverse group ranging from small-bodied forms to very large ones, radiating into multiple orders and colonizing

595-921: A result, rather than a cause, of the plate tectonic forces that led to the propagation of rifting from the Central to the North Atlantic. Mountain building continued along the North America Cordillera in response to subduction of the Farallon plate beneath the North American Plate. Along the central section of the North American margin, crustal shortening of the Cretaceous to Paleocene Sevier Orogen lessened and deformation moved eastward. The decreasing dip of

680-445: A shift from -k- to -t- (to Modern English bat ) influenced by Latin blatta , ' moth, nocturnal insect ' . The word bat was probably first used in the early 1570s. The name Chiroptera derives from Ancient Greek : χείρ – cheir , ' hand ' and πτερόν – pteron , ' wing ' . The delicate skeletons of bats do not fossilise well; it is estimated that only 12% of bat genera that lived have been found in

765-777: A sister taxon to odd-toed ungulates (Perissodactyla). Euarchontoglires (primates, treeshrews, rodents, rabbits) [REDACTED] Eulipotyphla (hedgehogs, shrews, moles, solenodons) [REDACTED] Chiroptera (bats) [REDACTED] Pholidota (pangolins) [REDACTED] Carnivora (cats, hyenas, dogs, bears, seals, weasels) [REDACTED] [REDACTED] Perissodactyla (horses, tapirs, rhinos) [REDACTED] Cetartiodactyla (camels, ruminants, whales) [REDACTED] [REDACTED] The flying primate hypothesis proposed that when adaptations to flight are removed, megabats are allied to primates by anatomical features not shared with microbats and thus flight evolved twice in mammals. Genetic studies have strongly supported

850-483: A study published in 2018, from about 56 to 48 Ma, annual air temperatures over land and at mid-latitude averaged about 23–29 °C (± 4.7 °C). For comparison, this was 10 to 15 °C higher than the current annual mean temperatures in these areas. This rapid rise in global temperatures and intense greenhouse conditions were due to a sudden increase in levels of atmospheric carbon dioxide (CO 2 ) and other greenhouse gases . An accompanying rise in humidity

935-621: Is 150 meters (490 ft) to 170 meters (560 ft) the highest elevation is 213 meters (699 ft), located roughly in the middle. The vegetation of the flat areas consists mainly of xerophytic shrubs , including wormwood , saltwort and ephemeral plants . In the slopes of hills and ridges there are thickets of dzhuzgun , sand acacia , astragalus , kandym and chingil . Paleogene The Paleogene Period ( IPA : / ˈ p eɪ l i . ə dʒ iː n , - l i . oʊ -, ˈ p æ l i -/ PAY -lee-ə-jeen, -⁠lee-oh-, PAL -ee- ; also spelled Palaeogene or Palæogene )

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1020-720: Is a geologic period and system that spans 43 million years from the end of the Cretaceous Period 66 Ma (million years ago) to the beginning of the Neogene Period 23.03 Ma. It is the first period of the Cenozoic Era , the tenth period of the Phanerozoic and is divided into the Paleocene , Eocene , and Oligocene epochs. The earlier term Tertiary Period was used to define the time now covered by

1105-502: Is associated with the Cretaceous–Paleogene extinction event. The boundary is defined as the rusty colored base of a 50 cm thick clay , which would have been deposited over only a few days. Similar layers are seen in marine and continental deposits worldwide. These layers include the iridium anomaly, microtektites , nickel -rich spinel crystals and shocked quartz , all indicators of a major extraterrestrial impact. The remains of

1190-1147: Is not believed to originate more than 23 mya. Pteropodidae (megabats) [REDACTED] Megadermatidae (false vampire bats) [REDACTED] Craseonycteridae (Kitti's hog-nosed bat) [REDACTED] Rhinopomatidae (mouse-tailed bats) [REDACTED] Hipposideridae (Old World leaf-nosed bats) [REDACTED] Rhinolophidae (horseshoe bats) [REDACTED] Miniopteridae (long winged bat) [REDACTED] Noctilionidae (fisherman bats) [REDACTED] Mormoopidae ( Pteronotus ) [REDACTED] Mystacinidae (New Zealand short-tailed bats) [REDACTED] Thyropteridae (disc-winged bats) Furipteridae [REDACTED] Mormoopidae ( Mormoops ) [REDACTED] Phyllostomidae (New World leaf-nosed bats) [REDACTED] Molossidae (free-tailed bats) [REDACTED] Emballonuridae (sac-winged bats) [REDACTED] Myzopodidae (sucker-footed bats) Emballonuridae ( Taphozous ) [REDACTED] Natalidae (funnel-eared bats) [REDACTED] Vespertilionidae (vesper bats) [REDACTED] Genetic evidence indicates that megabats originated during

1275-454: Is reflected in an increase in kaolinite in sediments, which forms by chemical weathering in hot, humid conditions. Tropical and subtropical forests flourished and extended into polar regions. Water vapour (a greenhouse gas) associated with these forests also contributed to the greenhouse conditions. The initial rise in global temperatures was related to the intrusion of magmatic sills into organic-rich sediments during volcanic activity in

1360-597: The Bering Straits between North America and Eurasia allowing the movement of land animals between the two continents. The PETM was followed by the less severe Eocene Thermal Maximum 2 (c. 53.69 Ma), and the Eocene Thermal Maximum 3 (c. 53 Ma). The early Eocene warm conditions were brought to an end by the Azolla event . This change of climate at about 48.5 Ma, is believed to have been caused by

1445-873: The Canadian Arctic Archipelago , Svalbard and northern Greenland resulting in the Eureka Orogeny . From c. 47 Ma, the eastern margin of Greenland was cut by the Reykjanes Ridge (the northeastern branch of the Mid-Atlantic Ridge) propagating northwards and splitting off the Jan Mayen microcontinent . After c. 33 Ma seafloor spreading in Labrador Sea and Baffin Bay gradually ceased and seafloor spreading focused along

1530-901: The Izu-Bonin-Mariana and Tonga-Kermadec arcs. Subduction of the Farallon Plate beneath the American plates continued from the Late Cretaceous. The Kula-Farallon spreading ridge lay to its north until the Eocene (c. 55 Ma), when the northern section of the plate split forming the Vancouver/Juan de Fuca Plate . In the Oligocene (c. 28 Ma), the first segment of the Pacific–Farallon spreading ridge entered

1615-783: The Tasmanian Passage in the Eocene and deep ocean routes opening from the mid Oligocene. Rifting between the Antarctic Peninsula and the southern tip of South America formed the Drake Passage and opened the Southern Ocean also during this time, completing the breakup of Gondwana. The opening of these passages and the creation of the Southern Ocean established the Antarctic Circumpolar Current . Glaciers began to build across

1700-636: The Taurides in the east. From the Late Cretaceous into the early Paleocene, Africa began to converge with Eurasia. The irregular outlines of the continental margins, including the Adriatic promontory (Adria) that extended north from the African Plate, led to the development of several short subduction zones, rather than one long system. In the western Mediterranean, the European Plate

1785-475: The air and marine ecosystems by the Eocene . Birds , the only surviving group of dinosaurs, quickly diversified from the very few neognath and paleognath clades that survived the extinction event, also radiating into multiple orders, colonizing different ecosystems and achieving an extreme level of morphological diversity. Percomorph fish, the most diverse group of vertebrates today, first appeared near

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1870-399: The echolocating microbats . But more recent evidence has supported dividing the order into Yinpterochiroptera and Yangochiroptera , with megabats as members of the former along with several species of microbats. Many bats are insectivores , and most of the rest are frugivores (fruit-eaters) or nectarivores (nectar-eaters). A few species feed on animals other than insects; for example,

1955-431: The flying foxes , with the giant golden-crowned flying fox ( Acerodon jubatus ) reaching a weight of 1.6 kg (3.5 lb) and having a wingspan of 1.7 m (5 ft 7 in). The second largest order of mammals after rodents , bats comprise about 20% of all classified mammal species worldwide, with over 1,400 species. These were traditionally divided into two suborders: the largely fruit-eating megabats , and

2040-542: The monophyly of bats and the single origin of mammal flight. An independent molecular analysis trying to establish the dates when bat ectoparasites ( bedbugs ) evolved came to the conclusion that bedbugs similar to those known today (all major extant lineages, all of which feed primarily on bats) had already diversified and become established over 100 mya (i.e., long before the oldest records for bats, 52 mya), suggesting that they initially all evolved on non-bat hosts and "bats were colonized several times independently, unless

2125-648: The trench leading to the development of the Dinarides, Hellenides and Tauride mountain chains as the passive margin sediments of Adria were scrapped off onto the Eurasia crust during subduction. The Zagros mountain belt stretches for c. 2000 km from the eastern border of Iraq to the Makran coast in southern Iran . It formed as a result of the convergence and collision of the Arabian and Eurasian plates as

2210-469: The vampire bats feed on blood . Most bats are nocturnal , and many roost in caves or other refuges; it is uncertain whether bats have these behaviours to escape predators . Bats are present throughout the world, with the exception of extremely cold regions. They are important in their ecosystems for pollinating flowers and dispersing seeds; many tropical plants depend entirely on bats for these services. Bats provide humans with some direct benefits, at

2295-484: The Aktobe Region. The Shalkar Basin extends to the west. The desert is sandy and receives very little rainfall. Its sands are subject to eolic action, forming mounds, ridges and dunes . The Greater Barsuki, also known as "Major Barsuki", has a length of 120 kilometers (75 mi), an average width of 25 kilometers (16 mi) and an area of 3,300 square kilometers (1,300 sq mi). It stretches from

2380-509: The Antarctica continent that now lay isolated in the south polar region and surrounded by cold ocean waters. These changes contributed to the fall in global temperatures and the beginning of icehouse conditions. Extensional stresses from the subduction zone along the northern Neotethys resulted in rifting between Africa and Arabia, forming the Gulf of Aden in the late Eocene. To the west, in

2465-725: The Central Andes were dominated by the subduction of oceanic crust and the Southern Andes were impacted by the subduction of the Farallon-East Antarctic ocean ridge. The Caribbean Plate is largely composed of oceanic crust of the Caribbean Large Igneous Province that formed during the Late Cretaceous. During the Late Cretaceous to Paleocene, subduction of Atlantic crust was established along its northern margin, whilst to

2550-723: The Eocene-Oligocene boundary and the present day Late Cenozoic ice age began. The Paleogene began with the brief but intense " impact winter " caused by the Chicxulub impact , which was followed by an abrupt period of warming. After temperatures stabilised, the steady cooling and drying of the Late Cretaceous-Early Paleogene Cool Interval that had spanned the last two ages of the Late Cretaceous continued, with only

2635-667: The Farallon Plate beneath the western edge of South America continued from the Mesozoic. Over the Paleogene, changes in plate motion and episodes of regional slab shallowing and steepening resulted in variations in the magnitude of crustal shortening and amounts of magmatism along the length of the Andes . In the Northern Andes, an oceanic plateau with volcanic arc was accreted during the latest Cretaceous and Paleocene, whilst

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2720-527: The Greenland and northwest European margins and is associated with the proto-Icelandic mantle plume , which rose beneath the Greenland lithosphere at c. 65 Ma. There were two main phases of volcanic activity with peaks at c. 60 Ma and c. 55 Ma. Magmatism in the British and Northwest Atlantic volcanic provinces occurred mainly in the early Palaeocene, the latter associated with an increased spreading rate in

2805-702: The Himalayas in India through Myanmar ( West Burma block ) Sumatra , Java to West Sulawesi . During the Late Cretaceous to Paleogene, the northward movement of the Indian Plate led to the highly oblique subduction of the Neotethys along the edge of the West Burma block and the development of a major north-south transform fault along the margin of Southeast Asia to the south. Between c. 60 and 50 Ma,

2890-734: The India-Eurasia collision continued, movement of material away from the collision zone was accommodated along, and extended, the already existing major strike slip systems of the region. During the Paleocene, seafloor spreading along the Mid-Atlantic Ridge propagated from the Central Atlantic northwards between North America and Greenland in the Labrador Sea (c. 62 Ma) and Baffin Bay (c. 57 Ma), and, by

2975-427: The Labrador Sea, whilst northeast Atlantic magmatism occurred mainly during the early Eocene and is associated with a change in the spreading direction in the Labrador Sea and the northward drift of Greenland. The locations of the magmatism coincide with the intersection of propagating the rifts and large-scale, pre-existing lithospheric structures, which acted as channels to the surface for the magma . The arrival of

3060-523: The Neotethys Ocean closed and is composed sediments scrapped from the descending Arabian Plate. From the Late Cretaceous, a volcanic arc developed on the Eurasia margin as the Neotethys crust was subducted beneath it. A separate intra-oceanic subduction zone in the Neotethys resulted in the obuction of ocean crust onto the Arabian margin in the Late Cretaceous to Paleocene, with break-off of

3145-607: The Neotethys Ocean lying between it and southern Eurasia. Debate about the amount of deformation seen in the geological record in the India–Eurasia collision zone versus the size of Greater India, the timing and nature of the collision relative to the decrease in plate velocity, and explanations for the unusually high velocity of the Indian plate have led to several models for Greater India: 1) A Late Cretaceous to early Paleocene subduction zone may have lain between India and Eurasia in

3230-534: The Neotethys, dividing the region into two plates, subduction was followed by collision of India with Eurasia in the middle Eocene. In this model Greater India would have been less than 900 km wide; 2) Greater India may have formed a single plate, several thousand kilometres wide, with the Tethyan Himalaya microcontinent separated from the Indian continent by an oceanic basin . The microcontinent collided with southern Eurasia c. 58 Ma (late Paleocene), whilst

3315-608: The North American subduction zone near Baja California leading to major strike-slip movements and the formation of the San Andreas Fault . At the Paleogene-Neogene boundary, spreading ceased between the Pacific and Farallon plates and the Farallon Plate split again forming the present date Nazca and Cocos plates. The Kula Plate lay between Pacific Plate and North America. To the north and northwest it

3400-504: The North Atlantic Igneous Province, between about 56 and 54 Ma, which rapidly released large amounts of greenhouse gases into the atmosphere. This warming led to melting of frozen methane hydrates on continental slopes adding further greenhouses gases. It also reduced the rate of burial of organic matter as higher temperatures accelerated the rate of bacterial decomposition which released CO 2 back into

3485-485: The Oligocene. The Paleogene is divided into three series / epochs : the Paleocene, Eocene, and Oligocene. These stratigraphic units can be defined globally or regionally. For global stratigraphic correlation, the International Commission on Stratigraphy (ICS) ratify global stages based on a Global Boundary Stratotype Section and Point (GSSP) from a single formation (a stratotype ) identifying

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3570-650: The Pacific Plate moved north. At c. 47 Ma, movement of the hotspot ceased and the Pacific Plate motion changed from northward to northwestward in response to the onset of subduction along its western margin. This resulted in a 60 degree bend in the seamount chain. Other seamount chains related to hotspots in the South Pacific show a similar change in orientation at this time. Slow seafloor spreading continued between Australia and East Antarctica. Shallow water channels probably developed south of Tasmania opening

3655-560: The Pacific, Farallon, Kula and Izanagi plates. The central Pacific Plate grew by seafloor spreading as the other three plates were subducted and broken up. In the southern Pacific, seafloor spreading continued from the Late Cretaceous across the Pacific–Antarctic, Pacific-Farallon and Farallon–Antarctic mid ocean ridges. The Izanagi-Pacific spreading ridge lay nearly parallel to the East Asian subduction zone and between 60–50 Ma

3740-609: The Paleogene Period and subsequent Neogene Period; despite no longer being recognized as a formal stratigraphic term , "Tertiary" still sometimes remains in informal use. Paleogene is often abbreviated "Pg", although the United States Geological Survey uses the abbreviation " Pe " for the Paleogene on the Survey's geologic maps. Much of the world's modern vertebrate diversity originated in

3825-459: The Paleogene, and lasted from 33.9 Ma to 23.03 Ma. It is divided into two stages: the Rupelian 33.9 Ma to 27.82 Ma; and, Chattian 27.82 - 23.03 Ma. The GSSP for the base of the Oligocene is at Massignano , near Ancona , Italy . The extinction the hantkeninid planktonic foraminifera is the key marker for the Eocene-Oligocene boundary, which was a time of climate cooling that led to widespread changes in fauna and flora. The final stages of

3910-441: The West, bats are popularly associated with darkness, malevolence, witchcraft, vampires , and death. An older English name for bats is flittermouse , which matches their name in other Germanic languages (for example German Fledermaus and Swedish fladdermus ), related to the fluttering of wings. Middle English had bakke , most likely cognate with Old Swedish natbakka ( ' night-bat ' ), which may have undergone

3995-551: The air. This suggests that this bat did not fly as much as modern bats, but flew from tree to tree and spent most of its time climbing or hanging on branches. The distinctive features of the Onychonycteris fossil also support the hypothesis that mammalian flight most likely evolved in arboreal locomotors, rather than terrestrial runners. This model of flight development, commonly known as the "trees-down" theory, holds that bats first flew by taking advantage of height and gravity to drop down on to prey, rather than running fast enough for

4080-459: The area southeast of Begimbet in the south to a little to the northeast of Shalkar town. The Lesser Barsuki, also known as "Minor Barsuki", lies to the east of its greater neighbor and stretches for 80 kilometers (50 mi) from Butakov Bay in the North Aral Sea by Akespe , to a little to the northwest of Karashokat in the Kyzylorda Region. Its width is between 10 kilometers (6.2 mi) and 25 kilometers (16 mi). The average height

4165-423: The base of the Eocene is at Dababiya, near Luxor , Egypt and is marked by the start of a significant variation in global carbon isotope ratios, produced by a major period of global warming. The change in climate was due to a rapid release of frozen methane clathrates from seafloor sediments at the beginning of the Paleocene-Eocene thermal maximum (PETM). The Oligocene is the third and youngest series/epoch of

4250-425: The breakup of Pangaea occurred during the Paleogene as Atlantic Ocean rifting and seafloor spreading extended northwards, separating the North America and Eurasian plates, and Australia and South America rifted from Antarctica , opening the Southern Ocean . Africa and India collided with Eurasia forming the Alpine-Himalayan mountain chains and the western margin of the Pacific Plate changed from

4335-430: The brief interruption of the Latest Danian Event (c. 62.2 Ma) when global temperatures rose. There is no evidence for ice sheets at the poles during the Paleocene. The relatively cool conditions were brought to an end by the Thanetian Thermal Event, and the beginning of the PETM. This was one of the warmest times of the Phanerozoic eon, during which global mean surface temperatures increased to 31.6 °C. According to

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4420-406: The cold circumpolar current. Dense polar waters sank into the deep oceans and moved northwards, reducing global ocean temperatures. This cooling may have occurred over less than 100,000 years and resulted in a widespread extinction in marine life. By the Eocene-Oligocene boundary, sediments deposited in the ocean from glaciers indicate the presence of an ice sheet in western Antarctica that extended to

4505-418: The collision of the Tethyan (Tibetan) Himalayas , the leading edge of Greater India, with the Lhasa Terrane of Tibet (southern Eurasian margin), along the Indus-Yarling-Zangbo suture zone . To the south of this zone, the Himalaya are composed of metasedimentary rocks scraped off the now subducted Indian continental crust and mantle lithosphere as the collision progressed. Palaeomagnetic data place

4590-430: The cooler oceans also reduced moisture in the atmosphere and increased aridity. By the early Oligocene, the North American and Eurasian tropical and subtropical forests were replaced by dry woodlands and widespread grasslands. The Early Oligocene Glacial Maximum lasted for about 200,000 years, and the global mean surface temperature continued to decrease gradually during the Rupelian . A drop in global sea levels during

4675-504: The cost of some disadvantages. Bat dung has been mined as guano from caves and used as fertiliser. Bats consume insect pests, reducing the need for pesticides and other insect management measures. They are sometimes numerous enough and close enough to human settlements to serve as tourist attractions, and they are used as food across Asia and the Pacific Rim . However, fruit bats are frequently considered pests by fruit growers. Due to their physiology, bats are one type of animal that acts as

4760-528: The crater are found at Chicxulub on the Yucatan Peninsula in Mexico . The extinction of the non-avian dinosaurs , ammonites and dramatic changes in marine plankton and many other groups of organisms, are also used for correlation purposes. The Eocene is the second series/epoch of the Paleogene, and lasted from 56.0 Ma to 33.9 Ma. It is divided into four stages: the Ypresian 56.0 Ma to 47.8 Ma; Lutetian 47.8 Ma to 41.2 Ma; Bartonian 41.2 Ma to 37.71 Ma; and, Priabonian 37.71 Ma to 33.9 Ma. The GSSP for

4845-457: The disruption of the Chicxulub impact settled, a period of cool and dry conditions continued from the Late Cretaceous. At the Paleocene-Eocene boundary global temperatures rose rapidly with the onset of the Paleocene-Eocene Thermal Maximum (PETM). By the middle Eocene, temperatures began to drop again and by the late Eocene (c. 37 Ma) had decreased sufficiently for ice sheets to form in Antarctica. The global climate entered icehouse conditions at

4930-423: The early Eocene , and belong within the four major lines of microbats. Two new suborders have been proposed; Yinpterochiroptera includes the Pteropodidae , or megabat family, as well as the families Rhinolophidae , Hipposideridae , Craseonycteridae , Megadermatidae , and Rhinopomatidae . Yangochiroptera includes the other families of bats (all of which use laryngeal echolocation), a conclusion supported by

5015-497: The early Eocene (c. 54 Ma), into the northeastern Atlantic between Greenland and Eurasia. Extension between North America and Eurasia, also in the early Eocene, led to the opening of the Eurasian Basin across the Arctic, which was linked to the Baffin Bay Ridge and Mid-Atlantic Ridge to the south via major strike slip faults. From the Eocene and into the early Oligocene, Greenland acted as an independent plate moving northwards and rotating anticlockwise. This led to compression across

5100-415: The early Oligocene, flood basalts erupted across Ethiopia , northeast Sudan and southwest Yemen as the Afar mantle plume began to impact the base of the African lithosphere. Rifting across the southern Red Sea began in the mid Oligocene, and across the central and northern Red Sea regions in the late Oligocene and early Miocene. Climatic conditions varied considerably during the Paleogene. After

5185-406: The end of the Cretaceous but saw a very rapid radiation into their modern order and family-level diversity during the Paleogene, achieving a diverse array of morphologies. The Paleogene is marked by considerable changes in climate from the Paleocene–Eocene Thermal Maximum , through global cooling during the Eocene to the first appearance of permanent ice sheets in the Antarctic at the beginning of

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5270-487: The evolutionary origin of bats has been grossly underestimated." Fleas , as a group, are quite old (most flea families formed around the end of the Cretaceous ), but no analyses have provided estimates for the age of the flea lineages associated with bats. The oldest known members of a different lineage of bat ectoparasites ( bat flies ), however, are from roughly 20 mya, well after the origin of bats. The bat-ectoparasitic earwig family Arixeniidae has no fossil record, but

5355-491: The first fossil mammals whose colouration has been discovered: both were reddish-brown. Bats were formerly grouped in the superorder Archonta , along with the treeshrews (Scandentia), colugos (Dermoptera), and primates . Modern genetic evidence now places bats in the superorder Laurasiatheria , with its sister taxon as Ferungulata , which includes carnivorans , pangolins , odd-toed ungulates , even-toed ungulates , and cetaceans . One study places Chiroptera as

5440-581: The fossil record. Most of the oldest known bat fossils were already very similar to modern microbats, such as Archaeopteropus (32 million years ago). The oldest known bat fossils include Archaeonycteris praecursor and Altaynycteris aurora (55-56 million years ago), both known only from isolated teeth. The oldest complete bat skeleton is Icaronycteris gunnelli (52 million years ago), known from two skeletons discovered in Wyoming. The extinct bats Palaeochiropteryx tupaiodon and Hassianycteris kumari , both of which lived 48 million years ago, are

5525-404: The late Eocene (c. 37 Ma) there is evidence of glaciation in Antarctica. Changes in deep ocean currents, as Australia and South America moved away from Antarctica opening the Drake and Tasmanian passages, were responsible for the drop in global temperatures. The warm waters of the South Atlantic, Indian and South Pacific oceans extended southward into the opening Southern Ocean and became part of

5610-409: The leading northeastern edge of Greater India collided with the West Burma block resulting in deformation and metamorphism . During the middle Eocene, north-dipping subduction resumed along the southern edge of Southeast Asia, from west Sumatra to West Sulawesi, as the Australian Plate drifted slowly northwards. Collision between India and the West Burma block was complete by the late Oligocene. As

5695-440: The lower boundary of the stage. The Paleocene is the first series/epoch of the Paleogene and lasted from 66.0 Ma to 56.0 Ma. It is divided into three stages: the Danian 66.0 - 61.6 Ma; Selandian 61.6 - 59.2 Ma; and, Thanetian 59.2 - 56.0 Ma. The GSSP for the base of the Cenozoic, Paleogene and Paleocene is at Oued Djerfane, west of El Kef , Tunisia . It is marked by an iridium anomaly produced by an asteroid impact, and

5780-466: The mid Oligocene indicates major growth of the Antarctic glacial ice sheet. In the Late Oligocene , global temperatures began to warm slightly, though they continued to be significantly lower than during the previous epochs of the Paleogene and polar ice remained. Bat (traditional): (present): Bats are flying mammals of the order Chiroptera ( / k aɪ ˈ r ɒ p t ər ə / ). With their forelimbs adapted as wings , they are

5865-409: The northeast Atlantic. By the late Oligocene, the plate boundary between North America and Eurasia was established along the Mid-Atlantic Ridge, with Greenland attached to the North American plate again, and the Jan Mayen microcontinent part of the Eurasian Plate, where its remains now lie to the east and possibly beneath the southeast of Iceland. The North Atlantic Igneous Province stretches across

5950-574: The ocean. The development of the circumpolar current led to changes in the oceans, which in turn reduced atmospheric CO 2 further. Increasing upwellings of cold water stimulated the productivity of phytoplankton , and the cooler waters reduced the rate of bacterial decay of organic matter and promoted the growth of methane hydrates in marine sediments. This created a positive feedback cycle where global cooling reduced atmospheric CO 2 and this reduction in CO 2 lead to changes which further lowered global temperatures. The decrease in evaporation from

6035-423: The oceans. The (relatively) sudden climatic changes associated with the PETM resulted in the extinction of some groups of fauna and flora and the rise of others. For example, with the warming of the Arctic Ocean, around 70% of deep sea foraminifera species went extinct, whilst on land many modern mammals, including primates , appeared. Fluctuating sea levels meant, during low stands, a land bridge formed across

6120-446: The only mammals capable of true and sustained flight . Bats are more agile in flight than most birds, flying with their very long spread-out digits covered with a thin membrane or patagium . The smallest bat, and arguably the smallest extant mammal , is Kitti's hog-nosed bat , which is 29–34 mm (1.1–1.3 in) in length, 150 mm (5.9 in) across the wings and 2–2.6 g (0.071–0.092 oz) in mass. The largest bats are

6205-518: The present day Indian continent further south at the time of collision and decrease in plate velocity, indicating the presence of a large region to the north of India that has now been subducted beneath the Eurasian Plate or incorporated into the mountain belt. This region, known as Greater India, formed by extension along the northern margin of India during the opening of the Neotethys. The Tethyan Himalaya block lay along its northern edge, with

6290-399: The proto-Iceland plume has been considered the driving mechanism for rifting in the North Atlantic. However, that rifting and initial seafloor spreading occurred prior to the arrival of the plume, large scale magmatism occurred at a distance to rifting, and that rifting propagated towards, rather than away from the plume, has led to the suggestion the plume and associated magmatism may have been

6375-684: The southwest, an island arc collided with the northern Andes forming an east dipping subduction zone where Caribbean lithosphere was subducted beneath the South American margin. During the Eocene (c. 45 Ma), subduction of the Farallon Plate along the Central American subduction zone was (re)established. Subduction along the northern section of the Caribbean volcanic arc ceased as the Bahamas carbonate platform collided with Cuba and

6460-414: The spreading ridge began to be subducted. By c. 50 Ma, the Pacific Plate was no longer surrounded by spreading ridges, but had a subduction zone along its western edge. This changed the forces acting on the Pacific Plate and led to a major reorganisation of plate motions across the entire Pacific region. The resulting changes in stress between the Pacific and Philippine Sea plates initiated subduction along

6545-479: The subducted oceanic plate close to the Arabian margin occurring during the Eocene. Continental collision began during the Eocene c. 35 Ma and continued into the Oligocene to c. 26 Ma. The Indian continent rifted from Madagascar at c. 83 Ma and drifted rapidly (c. 18 cm/yr in the Paleocene) northwards towards the southern margin of Eurasia. A rapid decrease in velocity to c. 5 cm/yr in the early Eocene records

6630-538: The subducting Farallon Plate led to a flat-slab segment that increased friction between this and the base of the North American Plate. The resulting Laramide Orogeny , which began the development of the Rocky Mountains , was a broad zone of thick-skinned deformation , with faults extending to mid-crustal depths and the uplift of basement rocks that lay to the east of the Sevier belt, and more than 700km from

6715-669: The trench. With the Laramide uplift the Western Interior Seaway was divided and then retreated. During the mid to late Eocene (50–35 Ma), plate convergence rates decreased and the dip of the Farallon slab began to steepen. Uplift ceased and the region largely levelled by erosion . By the Oligocene, convergence gave way to extension, rifting and widespread volcanism across the Laramide belt. Ocean-continent convergence accommodated by east dipping subduction zone of

6800-485: The velocity of the plate did not decrease until c. 50 Ma when subduction rates dropped as young, oceanic crust entered the subduction zone; 3) This model assigns older dates to parts of Greater India, which changes its paleogeographic position relative to Eurasia and creates a Greater India formed of extended continental crust 2000 - 3000 km wide. The Alpine-Himalayan Orogenic Belt in Southeast Asia extends from

6885-525: The western Mediterranean arc of the Tell, Rif, Betic and Apennine mountain chains. The rate of convergence was less than the subduction rate of the dense lithosphere of the western Mediterranean and roll-back of the subducting slab led to the arcuate structure of these mountain ranges. In the eastern Mediterranean, c. 35 Ma, the Anatolide-Tauride platform (northern part of Adria) began to enter

6970-627: Was being subducted beneath the Aleutian trench . Spreading between the Kula and Pacific and Farallon plates ceased c. 40 Ma and the Kula Plate became part of the Pacific Plate. The Hawaiian-Emperor seamount chain formed above the Hawaiian hotspot . Originally thought to be stationary within the mantle, the hotspot is now considered to have drifted south during the Paleocene to early Eocene, as

7055-550: Was followed by a c.10 million year pause in the convergence of Africa and Eurasia, connected with the onset of the opening of the North Atlantic Ocean as Greenland rifted from the Eurasian Plate in the Palaeocene. Convergence rates between Africa and Eurasia increased again in the early Eocene and the remaining oceanic basins between Adria and Europe closed. Between about 40 and 30 Ma, subduction began along

7140-625: Was replaced by strike-slip movements as a transform fault, extending from the Mid-Atlantic Ridge, connected with the northern boundary of the Caribbean Plate. Subduction now focused along the southern Caribbean arc ( Lesser Antilles ). By the Oligocene, the intra-oceanic Central American volcanic arc began to collide with northwestern South American. At the beginning of the Paleogene, the Pacific Ocean consisted of

7225-572: Was subducted southwards beneath the African Plate, whilst in the eastern Mediterranean, Africa was subducted beneath Eurasia along a northward dipping subduction zone. Convergence between the Iberian and European plates led to the Pyrenean Orogeny and, as Adria pushed northwards the Alps and Carpathian orogens began to develop. The collision of Adria with Eurasia in the early Palaeocene

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