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Nature ◽  
2021 ◽  
Vol 600 (7889) ◽  
pp. 450-455
Author(s):  
J. W. Marschalek ◽  
L. Zurli ◽  
F. Talarico ◽  
T. van de Flierdt ◽  
P. Vermeesch ◽  
...  

Author(s):  
I. S. Novikov ◽  

The data on regional geology, stratigraphy and geomorphology accumulated by now permit one to compile a reliable and fairly complete model of changes in the World Ocean level in the interval from the Cretaceous period to the present. Global changes in the level of the World Ocean are primarily associated with slow and prolonged (107–108 y.) manifestations of plate tectonics (spreading of the ocean floor and decrease in the area of continents against the background of the formation of mountain relief due to collision processes at their borders) and faster, but short-term (103–106 y.) processes associated with the withdrawal of large amounts of water during the formation of large continental ice sheets and its return to the World Ocean during interglacial periods. The impact of the tectonic factor throughout the entire period under review was unidirectional, but uneven and led to intermittent decrease in the World Ocean level from 250–300 m above the present level to the current level, taken as 0 m. Prolonged periods of stable position of the World Ocean level in the second half of the Cretaceous, Paleogene and Early Neogene at 300, 250, 200 and 150 m led to the formation of regional peneplanation planes near these levels. Moreover, younger surfaces have never completely cut off the previous, higher level, leaving its relics in the form of table elevations on the surface of the younger peneplain. In tectonically passive areas, the hypsometric position of these geomorphological elements and associated sediments has stratigraphic significance, allowing the researchers to estimate their age, and in the case of their displacement, to evaluate the age and amplitudes of neotectonic movements.


2021 ◽  
pp. 1-12
Author(s):  
Luca Pandolfi ◽  
Ran Calvo ◽  
Ari Grossman ◽  
Rivka Rabinovich

Abstract A revision of the rhinocerotid material from the Negev (Israel), dating back to the early Miocene (MN3 in the European Mammal Biochronology), highlights the presence of Brachypotherium and a taxon close to Gaindatherium in the Levantine corridor. A juvenile mandible, investigated using CT scanning, displays morphologically distinct characters consistent with Brachypotherium cf. B. snowi rather than with other Eurasian representatives of this genus. Some postcranial remains from the Negev, such as a humerus, display features that distinguish it among Miocene taxa. We attribute these postcrania to cf. Gaindatherium sp., a taxon never recorded outside the Siwaliks until now. This taxon dispersed into the Levantine region during the late early Miocene, following a pattern similar to other South Asian taxa. Brachypotherium cf. B. snowi probably occurred in the Levantine region and then in North Africa during the early Miocene because its remains are known from slightly younger localities such as Moghara (Egypt) and Jebel Zelten (Libya). The occurrence cf. Gaindatherium sp. represents a previously unrecorded range expansion out of Southeast Asia. These new records demonstrate the paleogeographic importance of the Levantine region showcasing the complex role of the Levantine corridor in intercontinental dispersals between Asia and Europe as well as Eurasia and Africa.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11793
Author(s):  
Sylvia Hofmann ◽  
Daniel Jablonski ◽  
Spartak N. Litvinchuk ◽  
Rafaqat Masroor ◽  
Joachim Schmidt

Background The Himalaya-Tibet orogen (HTO) presents an outstanding geologically active formation that contributed to, and fostered, modern Asian biodiversity. However, our concepts of the historical biogeography of its biota are far from conclusive, as are uplift scenarios for the different parts of the HTO. Here, we revisited our previously published data set of the tribe Paini extending it with sequence data from the most western Himalayan spiny frogs Allopaa and Chrysopaa and using them as an indirect indicator for the potential paleoecological development of Tibet. Methods We obtained sequence data of two mitochondrial loci (16S rRNA, COI) and one nuclear marker (Rag1) from Allopaa samples from Kashmir Himalaya as well as Chrysopaa sequence data from the Hindu Kush available from GenBank to complement our previous data set. A Maximum likelihood and dated Bayesian gene tree were generated based on the concatenated data set. To resolve the inconsistent placement of Allopaa, we performed different topology tests. Results Consistent with previous results, the Southeast Asian genus Quasipaa is sister to all other spiny frogs. The results further reveal a basal placement of Chrysopaa relative to Allopaa and Nanorana with an estimated age of ca. 26 Mya. Based on the topology tests, the phylogenetic position of Allopaa as a sister clade to Chaparana seems to be most likely, resulting in a paraphyletic genus Nanorana and a separation from the latter clade around 20 Mya, although a basal position of Allopaa to the genus Nanorana cannot be entirely excluded. Both, the placements of Chrysopaa and Allopaa support the presence of basal Paini lineages in the far northwestern part of the HTO, which is diametrically opposite end of the HTO with respect to the ancestral area of spiny frogs in Southeast Asia. These striking distributional patterns can be most parsimoniously explained by trans-Tibet dispersal during the late Oligocene (subtropical Chrysopaa) respectively early Miocene (warm temperate Allopaa). Within spiny frogs, only members of the monophyletic Nanorana+Paa clade are adapted to the colder temperate climates, indicating that high-altitude environments did not dominate in the HTO before ca. 15 Mya. Our results are consistent with fossil records suggesting that large parts of Tibet were characterized by subtropical to warm temperate climates at least until the early Miocene. They contradict prevalent geological models of a highly uplifted late Paleogene proto-Plateau.


2021 ◽  
Vol 9 ◽  
Author(s):  
Conrad C. Labandeira

Insect and mite galls on land plants have a spotty but periodically rich and abundant fossil record of damage types (DTs), ichnotaxa, and informally described gall morphotypes. The earliest gall is on a liverwort of the Middle Devonian Period at 385 million years ago (Ma). A 70-million-year-long absence of documented gall activity ensues. Gall activity resumes during the Pennsylvanian Period (315 Ma) on vegetative and reproductive axial organs of horsetails, ferns, and probably conifers, followed by extensive diversification of small, early hemipteroid galler lineages on seed-plant foliage during the Permian Period. The end-Permian (P-Tr) evolutionary and ecological crisis extinguished most gall lineages; survivors diversified whose herbivore component communities surpassed pre-P-Tr levels within 10 million years in the mid-to late Triassic (242 Ma). During the late Triassic and Jurassic Period, new groups of galling insects colonized Ginkgoales, Bennettitales, Pinales, Gnetales, and other gymnosperms, but data are sparse. Diversifying mid-Cretaceous (125–90 Ma) angiosperms hosted a major expansion of 24 gall DTs organized as herbivore component communities, each in overlapping Venn-diagram fashion on early lineages of Austrobaileyales, Laurales, Chloranthales, and Eurosidae for the Dakota Fm (103 Ma). Gall diversification continued into the Ora Fm (92 Ma) of Israel with another 25 gall morphotypes, but as ichnospecies on a different spectrum of plant hosts alongside the earliest occurrence of parasitoid attack. The End-Cretaceous (K-Pg) extinction event (66 Ma) almost extinguished host–specialist DTs; surviving gall lineages expanded to a pre-K-Pg level 10 million years later at the Paleocene-Eocene Thermal Maximum (PETM) (56 Ma), at which time a dramatic increase of land surface temperatures and multiplying of atmospheric pCO2 levels induced a significant level of increased herbivory, although gall diversity increased only after the PETM excursion and during the Early Eocene Climatic Optimum (EECO). After the EECO, modern (or structurally convergent) gall morphotypes originate in the mid-Paleogene (49–40 Ma), evidenced by the Republic, Messel, and Eckfeld floras on hosts different from their modern analogs. During subsequent global aridification, the early Neogene (20 Ma) Most flora of the Czech Republic records several modern associations with gallers and plant hosts congeneric with their modern analogs. Except for 21 gall DTs in New Zealand flora, the gall record decreases in richness, although an early Pleistocene (3 Ma) study in France documents the same plant surviving as an endemic northern Iran but with decreasing associational, including gall, host specificity.


2021 ◽  
Author(s):  
Peng Zhang ◽  
Lianfu Mei ◽  
Shao-Yong Jiang ◽  
Sihuang Xu ◽  
Raymond A. Donelick ◽  
...  

2021 ◽  
Author(s):  
Sylvia Hofmann ◽  
Daniel Jablonski ◽  
Spartak Litvinchuk ◽  
Rafaqat Masroor ◽  
Joachim Schmidt

AbstractBackgroundThe Himalaya-Tibet orogen (HTO) presents an outstanding geologically active formation that contributed to, and fostered, modern Asian biodiversity. However, our concepts of the historical biogeography of its biota are far from conclusive, as are uplift scenarios for the different parts of the HTO. Here, we revisited our previously published data set of the tribe Paini extending it with sequence data from the most western Himalayan spiny frogs Allopaa and Chrysopaa and using them as an indirect indicator for the paleoecological development of Tibet.MethodsWe obtained sequence data of two mitochondrial loci (16S rRNA, COI) and one nuclear marker (Rag1) from Allopaa samples from Kashmir Himalaya as well as Chrysopaa sequence data from the Hindu Kush available from GenBank to complement our previous data set. A Maximum likelihood and dated Bayesian gene tree were generated based on the concatenated data set. To resolve the inconsistent placement of Allopaa, we performed different topology tests.ResultsConsistent with previous results, the Southeast Asian genus Quasipaa is sister to all other spiny frogs. The results further reveal a basal placement of Chrysopaa relative to Allopaa and Nanorana with an estimated age of ca. 26 Mya. Based on the topology tests, the phylogenetic position of Allopaa as a sister clade to Chaparana seems to be most likely, resulting in a paraphyletic genus Nanorana and a separation from the latter clade around 20 Mya. Both, the placements of Chrysopaa and Allopaa support the presence of basal Paini lineages in the far north western part of the HTO, which is diametrically opposite end of the HTO with respect to the ancestral area of spiny frogs in Southeast Asia. These striking distributional patterns can be most parsimoniously explained by trans-Tibet dispersal during the late Oligocene (subtropical Chrysopaa) respectively early Miocene (warm temperate Allopaa). Within spiny frogs, only members of the monophyletic Nanorana+Paa clade are adapted to the colder temperate climates, indicating that high-altitude environments did not dominate in the HTO before ca. 15 Mya. Our results are consistent with fossil records suggesting that large parts of Tibet were characterized by subtropical to warm temperate climates at least until the early Miocene.


2021 ◽  
Vol 288 ◽  
pp. 01064
Author(s):  
Akimgali Kenzhegaliev ◽  
Assylbek Kanbetov ◽  
Dauren Kulbatyrov ◽  
Aiauzhan Shakhmanova ◽  
Ainagul Abilgaziyeva

While in the early neogene, tectonic and to a lesser extent climatic factors impacted on the sea level, at the present stage climatic, man-made and anthropogenic factors are at the forefront. As a result of an increase in the level of the Caspian Sea by more than 2.4 m, 35-40 thousand square meters km of territory was flooded, during the flooding and flooding of the coastal territory for the period 1978-1995 led to a change in natural, socio-economic and medico-ecological conditions. The consequences of rising sea levels led to the resettlement of about 100 thousand people living in the coastal flooded zone of the Northern Caspian Sea and many industrial facilities.


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