scholarly journals Neogene amphibians and reptiles (Caudata, Anura, Gekkota, Lacertilia, and Testudines) from the south of Western Siberia, Russia, and Northeastern Kazakhstan

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3025 ◽  
Author(s):  
Davit Vasilyan ◽  
Vladimir S. Zazhigin ◽  
Madelaine Böhme
Keyword(s):  
Middle Miocene ◽  
Western Siberia ◽  
Rana Temporaria ◽  
Bufo Bufo ◽  
Climatic Conditions ◽  
Early Pleistocene ◽  
Molecular Clocks ◽  
Fossil Remains ◽  
Western Asia ◽  
Fossil Records

BackgroundThe present-day amphibian and reptile fauna of Western Siberia are the least diverse of the Palaearctic Realm, as a consequence of the unfavourable climatic conditions that predominate in this region. The origin and emergence of these herpetofaunal groups are poorly understood. Aside from the better-explored European Neogene localities yielding amphibian and reptile fossil remains, the Neogene herpetofauna of Western Asia is understudied. The few available data need critical reviews and new interpretations, taking into account the more recent records of the European herpetofauna. The comparison of this previous data with that of European fossil records would provide data on palaeobiogeographic affiliations of the region as well as on the origin and emergence of the present-day fauna of Western Siberia. An overview of the earliest occurrences of certain amphibian lineages is still needed. In addition, studies that address such knowledge gaps can be useful for molecular biologists in their calibration of molecular clocks.Methods and ResultsIn this study, we considered critically reviewed available data from amphibian and reptile fauna from over 40 Western Siberian, Russian and Northeastern Kazakhstan localities, ranging from the Middle Miocene to Early Pleistocene. Herein, we provided new interpretations that arose from our assessment of the previously published and new data. More than 50 amphibians and reptile taxa were identified belonging to families Hynobiidae, Cryptobranchidae, Salamandridae, Palaeobatrachidae, Bombinatoridae, Pelobatidae, Hylidae, Bufonidae, Ranidae, Gekkonidae, Lacertidae, and Emydidae. Palaeobiogeographic analyses were performed for these groups and palaeoprecipitation values were estimated for 12 localities, using the bioclimatic analysis of herpetofaunal assemblages.ConclusionThe Neogene assemblage of Western Siberia was found to be dominated by groups of European affinities, such as Palaeobatrachidae,Bombina, Hyla,Bufo bufo, and a small part of this assemblage included Eastern Palaearctic taxa (e.g.Salamandrella,Tylototriton,Bufotes viridis). For several taxa (e.g.Mioproteus, Hyla, Bombina,Rana temporaria), the Western Siberian occurrences represented their most eastern Eurasian records. The most diverse collection of fossil remains was found in the Middle Miocene. Less diversity has been registered towards the Early Pleistocene, potentially due to the progressive cooling of the climate in the Northern Hemisphere. The results of our study showed higher-amplitude changes of precipitation development in Western Siberia from the Early Miocene to the Pliocene, than previously assumed.

scholarly journals Neogene amphibians and reptiles (Caudata, Anura, Gekotta, Lacertilia, Testudines) from south of Western Siberia, Russia and Northeastern Kazakhstan

2016 ◽  
Author(s):  
Davit Vasilyan ◽  
Vladimir Zazhigin ◽  
Madelaine Böhme
Keyword(s):  
Northern Hemisphere ◽  
Middle Miocene ◽  
Western Siberia ◽  
Bufo Bufo ◽  
Early Miocene ◽  
Early Pleistocene ◽  
Published Data ◽  
Molecular Clocks ◽  
Western Asia ◽  
Global Cooling

Background. Now-a-day territory of Western Siberia has the poorest diversity of amphibians and reptiles within the Palaearctic Realm, influenced by unfavourable climate. Less is known about the origin and emergence of it. Aside from better-explored European Neogene records of amphibians and reptiles, the Neogene herpetofauna of Western Asia is understudied. The few available studies on amphibian and reptile fossil assemblages need critical reviews and new interpretations considering the latest knowledge of the European record. The comparison with European record will provide data on palaeobiogeographic affiliations of the region as well as origin and emergence of the now-a-day fauna of Western Siberia. Beside these, a study providing overview about the earliest occurences of certain amphibian linages, that can be used for the calibration of the molecular clocks, is missing. Methods and Results. The amphibian and reptile fauna from over 40 Western Siberian, Russia and Northeastern Kazakhian localities ranging from Middle Miocene to Early Pleistocene has been studied. In the study the published data has been considered and critically reviewed and newly interpreted. More then 50 amphibian and reptile taxa has been identified belonging to families Hynobiidae, Cryptobranchidae, Salamandridae, Palaeobatrachidae, Bombinatoridae, Pelobatidae, Hylidae, Bufonidae, Ranidae, Gekkonidae, Lacertidae and Emydidae. Palaeobiogeographic analysis for those group has been done. For 12 localities, palaeoprecipitation values have been estimated using the bioclimatic analysis of herpetofaunal assemblage. Conclusions. The Neogene assemblage of Westren Sibera is dominated by groups (Palaeobatrachidae, Bombina, Hyla, Bufo bufo) with European affinities. A small part of assemblage includes Eastern Palaearctic taxa (e.g. Hynobiidae, Tylototriton, Bufotes viridis, R. arvalis). For several taxa (e.g. Mioproteus, Hyla, Bombina) the Western Siberian records of represent the most east Eurasian records of these groups. The most divers faunas are found in the Middle Miocene, whereas the poorest towards Early Pleistocene. This tendency could be referred to the progressive global cooling of the climate in Northern Hemisphere. Our results showed higher-amplitude changes of precipitation development in Western Siberia from Early Miocene to Pliocene, than earlier assumed.

scholarly journals Neogene amphibians and reptiles (Caudata, Anura, Gekotta, Lacertilia, Testudines) from south of Western Siberia, Russia and Northeastern Kazakhstan

2016 ◽  
Author(s):  
Davit Vasilyan ◽  
Vladimir Zazhigin ◽  
Madelaine Böhme
Keyword(s):  
Northern Hemisphere ◽  
Middle Miocene ◽  
Western Siberia ◽  
Bufo Bufo ◽  
Early Miocene ◽  
Early Pleistocene ◽  
Published Data ◽  
Molecular Clocks ◽  
Western Asia ◽  
Global Cooling

Background. Now-a-day territory of Western Siberia has the poorest diversity of amphibians and reptiles within the Palaearctic Realm, influenced by unfavourable climate. Less is known about the origin and emergence of it. Aside from better-explored European Neogene records of amphibians and reptiles, the Neogene herpetofauna of Western Asia is understudied. The few available studies on amphibian and reptile fossil assemblages need critical reviews and new interpretations considering the latest knowledge of the European record. The comparison with European record will provide data on palaeobiogeographic affiliations of the region as well as origin and emergence of the now-a-day fauna of Western Siberia. Beside these, a study providing overview about the earliest occurences of certain amphibian linages, that can be used for the calibration of the molecular clocks, is missing. Methods and Results. The amphibian and reptile fauna from over 40 Western Siberian, Russia and Northeastern Kazakhian localities ranging from Middle Miocene to Early Pleistocene has been studied. In the study the published data has been considered and critically reviewed and newly interpreted. More then 50 amphibian and reptile taxa has been identified belonging to families Hynobiidae, Cryptobranchidae, Salamandridae, Palaeobatrachidae, Bombinatoridae, Pelobatidae, Hylidae, Bufonidae, Ranidae, Gekkonidae, Lacertidae and Emydidae. Palaeobiogeographic analysis for those group has been done. For 12 localities, palaeoprecipitation values have been estimated using the bioclimatic analysis of herpetofaunal assemblage. Conclusions. The Neogene assemblage of Westren Sibera is dominated by groups (Palaeobatrachidae, Bombina, Hyla, Bufo bufo) with European affinities. A small part of assemblage includes Eastern Palaearctic taxa (e.g. Hynobiidae, Tylototriton, Bufotes viridis, R. arvalis). For several taxa (e.g. Mioproteus, Hyla, Bombina) the Western Siberian records of represent the most east Eurasian records of these groups. The most divers faunas are found in the Middle Miocene, whereas the poorest towards Early Pleistocene. This tendency could be referred to the progressive global cooling of the climate in Northern Hemisphere. Our results showed higher-amplitude changes of precipitation development in Western Siberia from Early Miocene to Pliocene, than earlier assumed.

Herpesvirus-Associated Proliferative Skin Disease in Frogs and Toads: Proposed Pathogenesis

2021 ◽  
pp. 030098582110063
Author(s):  
Francesco C. Origgi ◽  
Patricia Otten ◽  
Petra Lohmann ◽  
Ursula Sattler ◽  
Thomas Wahli ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Rana Temporaria ◽  
Skin Lesions ◽  
Bufo Bufo ◽  
Careful Examination ◽  
Altered Expression ◽  
Expression Of Genes ◽  
Cell Remodeling ◽  
Tissue Changes

A comparative study was carried out on common and agile frogs ( Rana temporaria and R. dalmatina) naturally infected with ranid herpesvirus 3 (RaHV3) and common toads ( Bufo bufo) naturally infected with bufonid herpesvirus 1 (BfHV1) to investigate common pathogenetic pathways and molecular mechanisms based on macroscopic, microscopic, and ultrastructural pathology as well as evaluation of gene expression. Careful examination of the tissue changes, supported by in situ hybridization, at different stages of development in 6 frogs and 14 toads revealed that the skin lesions are likely transient, and part of a tissue cycle necessary for viral replication in the infected hosts. Transcriptomic analysis, carried out on 2 naturally infected and 2 naïve common frogs ( Rana temporaria) and 2 naturally infected and 2 naïve common toads ( Bufo bufo), revealed altered expression of genes involved in signaling and cell remodeling in diseased animals. Finally, virus transcriptomics revealed that both RaHV3 and BfHV1 had relatively high expression of a putative immunomodulating gene predicted to encode a decoy receptor for tumor necrosis factor in the skin of the infected hosts. Thus, the comparable lesions in infected frogs and toads appear to reflect a concerted epidermal and viral cycle, with presumptive involvement of signaling and gene remodeling host and immunomodulatory viral genes.

scholarly journals Molecular clocks and the early evolution of metazoan nervous systems

2015 ◽  
Vol 370 (1684) ◽  
pp. 20150046 ◽  
Author(s):  
Gregory A. Wray
Keyword(s):  
Sensory Processing ◽  
Fossil Record ◽  
Sequence Data ◽  
Divergence Times ◽  
Molecular Clocks ◽  
Sense Organs ◽  
Animal Evolution ◽  
Nervous Systems ◽  
Nervous System Evolution ◽  
Fossil Records

The timing of early animal evolution remains poorly resolved, yet remains critical for understanding nervous system evolution. Methods for estimating divergence times from sequence data have improved considerably, providing a more refined understanding of key divergences. The best molecular estimates point to the origin of metazoans and bilaterians tens to hundreds of millions of years earlier than their first appearances in the fossil record. Both the molecular and fossil records are compatible, however, with the possibility of tiny, unskeletonized, low energy budget animals during the Proterozoic that had planktonic, benthic, or meiofaunal lifestyles. Such animals would likely have had relatively simple nervous systems equipped primarily to detect food, avoid inhospitable environments and locate mates. The appearance of the first macropredators during the Cambrian would have changed the selective landscape dramatically, likely driving the evolution of complex sense organs, sophisticated sensory processing systems, and diverse effector systems involved in capturing prey and avoiding predation.

Middle Miocene recovery of Caribbean reef corals: New data from the Tamana Formation, Trinidad

2001 ◽  
Vol 75 (3) ◽  
pp. 513-526 ◽  
Author(s):  
Kenneth G. Johnson
Keyword(s):  
Middle Miocene ◽  
New Records ◽  
Early Miocene ◽  
Early Pleistocene ◽  
Reef Corals ◽  
Rigorous Description ◽  
Caribbean Coral Reef ◽  
The Caribbean ◽  
Stratigraphic Ranges ◽  
Biotic Change

Caribbean coral reef communities were restructured by episodes of accelerated biotic change during the late Oligocene/early Miocene and the late Pliocene/early Pleistocene. However, rigorous description of the effects of rapid biotic change is problematic because preservation and exposure of coral-bearing deposits is not consistent in all stratigraphic intervals. In the Caribbean, early and middle Miocene exposures are more rare than late Miocene and Pliocene exposures. One exception is the late early to early middle Miocene Tamana Formation of Trinidad, and old and new collections from this unit were studied to determine the timing of recovery after the Oligocene/Miocene transition. A total of 41 species of zooxanthellate corals were recovered from the unit, including 21 new records. Within these assemblages, species first occurrences outnumber species last occurrences by a factor of four (31 first occurrences and eight last occurrences). The extension of the stratigraphic ranges of species previously first recorded in Pliocene sediments has reduced an apparent Pliocene pulse of origination, indicating that the Pliocene/Pleistocene transition was largely a result of accelerated extinction against a background of near-constant origination. The fact that few species last occur in the Tamana fauna indicates that the Oligocene/Miocene transition was complete by the end of the early Miocene.

Aeolian influx and related environmental conditions on Gran Canaria during the early Pleistocene

2018 ◽  
Vol 91 (1) ◽  
pp. 35-50 ◽  
Author(s):  
Inmaculada Menéndez ◽  
José Mangas ◽  
Esperança Tauler ◽  
Vidal Barrón ◽  
José Torrent ◽  
...  
Keyword(s):  
Late Quaternary ◽  
Textural Analysis ◽  
Climatic Conditions ◽  
Saharan Dust ◽  
Early Pleistocene ◽  
Middle Pleistocene ◽  
Quartz Content ◽  
Gran Canaria ◽  
Climatic Oscillations ◽  
Climatic Variations

AbstractThe island of Gran Canaria is regularly affected by dust falls due to its proximity to the Saharan desert. Climatic oscillations may affect the Saharan dust input to the island. Geochemical, mineralogical, and textural analysis was performed on a well-developed and representative early Pleistocene paleosol to examine Saharan dust contribution to Gran Canaria. Significant and variable Saharan dust content was identified in addition to weathering products such as iron oxides and clay minerals. Variations in quartz and iron oxide concentrations in the paleosol likely reflect different Saharan dust input in more/less-contrasted rhexistasic/biostatic climatic conditions. Linking the quartz content in Canarian soils, the Ingenio paleosol, and two Canarian loess-like deposits to different ages from the Quaternary, we hypothesized that the dust input should be lower (about 33–38%) throughout the early to middle Pleistocene than during the late Quaternary. The Saharan dust input to the Gran Canaria profile in the Pleistocene persisted in spite of climatic variations.

scholarly journals Petrography of the Siwalik sandstones, Amlekhganj-Suparitar area, central Nepal Himalaya

2003 ◽  
Vol 28 ◽  
Author(s):  
Naresh Kazi Tamrakar ◽  
Shuichiro Yokota ◽  
Suresh Das Shrestha
Keyword(s):  
Middle Miocene ◽  
Foreland Basin ◽  
Early Pleistocene ◽  
Nepal Himalaya ◽  
Central Nepal ◽  
Present Study Area ◽  
Mean Grain Size ◽  
Siwalik Group ◽  
Variation Trends ◽  
The Himalaya

Middle Miocene to early Pleistocene sedimentary sequence deposited in the foreland basin of the Himalaya is represented by the Siwalik Group. In the present study area the Siwalik Group extends in a NW-SE direction and well-exposed. Forty­four sandstone samples were studied for texture, fabric and composition in order to assess their petrographic properties and variation trends of these properties in stratigraphic levels. Sandstones were classified into sublitharenite, subarkose, lithic arenite, arkosic arenite and feldspathic graywacke and further thirteen sub-clans. Mean grain size (M) and Trask sorting coefficient (So) increase up-section. Recalculated quartz, matrix, modified maturity index (MMI), total cement (Ct), cement versus matrix index (CMI) and ratio of strong cement over total cement ((Cfc/Cs)/Ct) also increase, whilst packing proximity (PP), packing density (PD) and consolidation factor (Pcc) decrease up-section showing distinct trends, and therefore, these properties are promising in recognizing the older sandstones from the younger ones.

scholarly journals Buildings’ Air Quality in High Traffic

2015 ◽  
Vol 4 (6) ◽  
pp. 23-26
Author(s):  
Литвинова ◽  
Natalya Litvinova
Keyword(s):  
Carbon Monoxide ◽  
Air Quality ◽  
Western Siberia ◽  
Residential Buildings ◽  
Field Studies ◽  
Climatic Conditions ◽  
Sources Of Pollution ◽  
Mobile Sources ◽  
Air Intake ◽  
External Sources

The article presents the results of field studies of air quality depending on mobile sources of pollution. Studies of the carbon monoxide concentration was conducted for the climatic conditions of the South of Western Siberia. The object of the study was residential buildings. The studies were conducted under unfavorable wind speed. Processing of experimental data allowed to obtain the calculated dependences of dimensionless concentration of carbon monoxide (II) on the height of building’s facade under emissions from highways. According to the results of research a nomogram was constructed to determine the optimal air intake height of buildings located near roads of various traffic intensity. Research results and given recommendations allow considering external sources of pollution when designing ventilation of a building.

Sign in / Sign up

Export Citation Format

Share Document