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1.
A detailed ultra-high-resolution analysis of a 37-cm-long core of Upper Miocene lake sediments of the long-lived Lake Pannon has been performed. Despite a general stable climate at c. 11-9 Ma, several high-frequency oscillations of the paleoenvironments and depositional environments are revealed by the analysis over a short time span of less than 1000 years. Shifts of the lake level, associated with one major 3rd order flooding are reflected by all organisms by a cascade of environmental changes on a decadal scale. Within a few decades, the pollen record documents shifting vegetation zones due to the landward migration of the coast; the dinoflagellate assemblages switch towards "offshore-type" due to the increasing distance to the shore; the benthos is affected by low oxygen conditions due to the deepening. This general trend is interrupted by smaller scale cycles, which lack this tight interconnection. Especially, the pollen data document a clear cyclicity that is expressed by iterative low pollen concentration events. These "negative" cycles are partly reflected by dinoflagellate blooms suggesting a common trigger-mechanism and a connection between terrestrial environments and surface waters of Lake Pannon. The benthic fauna of the core, however, does not reflect these surface water cycles. This forcing mechanism is not understood yet but periodic climatic fluctuations are favoured as hypothesis instead of further lake level changes. Short phases of low precipitation, reducing pollen production and suppressing effective transport by local streams, might be a plausible mechanism. This study is the first hint towards solar activity related high-frequency climate changes during the Vallesian (Late Miocene) around Lake Pannon and should encourage further ultra-high-resolution analyses in the area.  相似文献   

2.
In the present article, we study the proboscidean remains from three upper Miocene localities of Northern Greece: Thermopigi (Serres), Neokaisareia (Pieria) and Platania (Drama). The material from the Turolian locality of Thermopigi includes only postcranial specimens. The morphological features of the scapula indicate the presence of the deinotheriid Deinotherium sp., whereas the rest of the specimens are morphologically distinct from Deinotherium and can be referred to Elephantimorpha indet. The material from Neokaisareia consists of a partial skeleton of a single individual and is attributed to the mammutid Mammut sp. (M. obliquelophus?). This taxon is known in Greece from the early–middle Turolian. The Platania proboscidean belongs to the tetralophodont amebelodontid Konobelodon cf. atticus. The genus Konobelodon was already present during the Vallesian of the wider area, but the lower tusk of the Platania shovel-tusker presents some morphological and metrical differences from the Vallesian representative, yet it has also smaller dimensions in its deciduous dentition than the morphologically similar Turolian specimens. The type locality of K. atticus is Pikermi (Attica, Greece), correlated to the middle Turolian, but the known biostratigraphic range of this species covers the entire Turolian. Platania is possibly correlated close to the Vallesian/Turolian boundary and the possible record of this species could document one of its earliest occurrences.  相似文献   

3.
《Geobios》1986,19(3):357-373
The revision of the fauna from Menacer (formerly Marceau), Algeria, has resulted in important modifications in the faunal list initially established by Arambourg (1959). Thirteen taxa are thereby counted. The Menacer locality has been classically paralleled with the Vallesian site of Bou Hanifia. Now the new faunal indications and the geologic data concerning the age of Menacer suggest, rather, a Turolian age.  相似文献   

4.
Long-lived lakes are often sites of spectacular endemic radiations. During the Oligocene to recent history of the Paratethys, large, long-lived (more than a million years) lakes with endemic faunas formed three times, in three different basins: the first in the Pannonian basin, the second in the Euxinian (Black Sea) basin, and the third in the Caspian basin. Because the Euxinian lake inherited much of the fauna of Lake Pannon, the three lakes together hosted two endemic radiations of molluscs. The most long-lived lake in the region was Lake Pannon, which persisted approximately seven million years from the late Middle Miocene to the Early Pliocene. Lake Pannon was formed by isolation from the sea. Changes in hydrological regime and/or water chemistry in addition to the relative lowstand which accompanied (or caused) the isolation almost completely exterminated the restricted marine fauna of the basin. A few highly euryhaline and marginal marine cardiids, dreissenids, and hydrobiids survived this environmental change. As in other fossil and extant long-lived lakes, the originally low-diversity fauna radiated into a high number of related endemic species (‘species flocks’) and genera in the expanding and ecologically vacated lake. Many originally freshwater taxa (unionids, sphaeriids, viviparids, valvatids, melanopsids, lymnaeids, planorbids) entered the lake as well, and some of them also gave rise to endemic clades. Evolution in both relict and freshwater immigrant groups led to the appearance of highly unusual shell shapes. Many lineages exhibit gradual morphological changes over one to several million years. More than 900 endemic mollusc species have been described from Lake Pannon, although this number includes junior synonyms, invalid species names, and highly similar chronospecies. Applying a conservative taxonomy, all these species belong to four bivalve and eight gastropod families. The high degree of endemism, however, is reflected by proposals of some authors to establish as many as five new families based on Lake Pannon endemics.  相似文献   

5.
Chalicotheriids are rare in the late Miocene mammal localities of Axios Valley, Macedonia (Greece). The new campaign of excavations, since 1972, has provided some specimens, which are studied in this article. They are coming from two different localities. The late early Vallesian locality of Pentalophos 1 (PNT) has provided a skull and a mandible of an Ancylotherium. The morphological characters of the PNT material as the small size, the long snout, the shallow mandibular corpus, the strong cingulum in the teeth, the short tooth rows and the short M3/m3 indicate that it differs from the known Turolian species A. pentelicum and allow the erection of a new species, named Ancylotherium hellenicum n. sp., which can be used as a biostratigraphic marker of the Vallesian. The middle Turolian locality Prochoma 1 (PXM) has provided only one M3, which is determined to the chalicotheriine Anisodon macedonicus. This species was earlier described from the middle Turolian locality Vathylakkos 3 (VAT) and the late Turolian one of Dytiko 3 (DKO) of Axios Valley. The biogeography and biostratigraphy of the late Miocene chalicotheres of the Greco-Iranian Palaeoprovince (GRIP), as well as their palaeoecology are also discussed. The common chalicothere of GRIP is A. pentelicum, expanded from the Balkans to Afganistan and ranging stratigraphically from the early to the late Turolian. Chalicotherium goldfussi is certainly present in GRIP and it also ranges from the early to the late Turolian; its possible Vallesian occurrence needs confirmation. The other two late Miocene chalicotheres of GRIP A. macedonicus and Kalimantsia bulgarica are restricted to the Turolian of the Balkan Peninsula.  相似文献   

6.
《Comptes Rendus Palevol》2016,15(7):791-812
The land mammal record of the Vallès-Penedès Basin (Catalonia, NE Spain) ranges from the early Miocene (Ramblian) to the late Miocene (Turolian), that is from about 20 to 7 Ma. Here we present an updated review of the mammal succession focusing on biochronology as well as on environmental and faunal changes. Based on faunal similarities with central Europe, we interpret this basin as a transitional zone between the forested environments of northern regions and the more arid landscapes of the inner Iberian Peninsula. The quality of the Vallès-Penedès record and its chronostratigraphic control is clearly better for the late Aragonian and the Vallesian (between 12.6–9.0 Ma), especially for small mammals. Therefore, we analyze small mammal diversity dynamics during this interval. Contrary to previous analyses, which found an abrupt extinction event coinciding with the early/late Vallesian boundary (the Vallesian Crisis), our results show that this pattern is due to uneven sampling. Instead, taxonomic richness slowly decreased since the late Vallesian as a result of a series of extinctions that mostly affected forest-dwelling taxa.  相似文献   

7.
8.
The gastropod γ-diversity of 12 Neogene lake systems is evaluated. In total, 1184 gastropod taxa from 119 localities are recorded deriving from the Early Miocene Rzehakia Lake System, the Early to Middle Miocene Dinarid Lake System, Lake Skopje, the Paratethyan Sarmatian lakes and the South German lakes, the Late Miocene Lake Pannon, the Pliocene lakes Dacia, Transylvania, Slavonia, Kosovo and Šoštanj as well as the Holocene Lake Petea. Each lake system is characterised according to its faunistic inventory and endemism. According to their gastropod faunas the lakes may be divided into pyrgulid-, hydrobiid-, viviparid- and planorbid-dominated ones. The generally high endemism rate is between 60 and 98%. Species diversity and generic diversity are strongly correlated. In contrast, neither endemism nor lake size are tightly linked with γ-diversity. Outstandingly high diversities such as observed for Lake Pannon are rather a result of the combined effect of autochthonous evolution in a long-lived system and accumulation of inherited elements. Examples of parallel evolution in lymnaeids and planorbids are presented.  相似文献   

9.
Vallesian (early Late Miocene) strata from the recently introduced Cañada section (province of Zaragoza, east Central Spain) have yielded fairly large insectivore assemblages. These show that, after the generally dry Aragonian, the Vallesian gave rise to more humid conditions that were favourable to insectivores, both in number of taxa, and in overall number of specimens. The assemblage of Cañada 8 (Biozone H) is dominated by shrews, whereas the assemblage of Cañada 10 (uppermost Biozone H) contains the oldest record of Desmanella in the area. This seems to signify a bioevent in which after millions of years of absence, talpids return to the area. In addition to the Vallesian assemblages, a small Turolian insectivore fauna has been recovered. On the basis of the rodents, Cañada 12 was assigned to Biozone L, and the insectivore assemblage is very similar to the assemblages from the Teruel basin of that zone. This implies that the discovery of Postpalerinaceus in Cañada 12 is the youngest published record of this large spiny hedgehog.  相似文献   

10.
This study presents the new fossil material of bovids from the recently discovered upper Miocene locality of Platania, Drama (Greece). The material was excavated from 2012 to 2016 and yielded approximately 760 specimens attributed to hipparions, rhinos, cervids, giraffids, suids, proboscideans, hyaenids, and turtles. The bovid material described here includes six taxa of Antilopinae and one of Bovinae. Antilopines are represented by Gazella sp., Gazella cf. ancyrensis, Prostrepsiceros aff. syridisi, cf. Palaeoreas, Palaeoryx minor nov. sp., and Tragoreas? aff. oryxoides. Bovines are recorded by a single boselaphine attributed to Miotragocerus sp. Departing from other Palaeoryx species, the new species P. minor has rather straight and weakly divergent horn-cores tilted backwards, obtuse facial and occipito-parietal angles, and smaller cranial and horn-core size, though associated with a proportionally large toothrow. Miotragocerus sp. from Platania seems to be conspecific to the Miotragocerus sp. from the end-Vallesian Nikiti-1 fauna (Greece). The bovid assemblage of Platania shows a mix of both Vallesian and Turolian taxa indicating a likely late Vallesian-early Turolian age.  相似文献   

11.
The Maragheh Formation, northwestern Iran,provides a local biostratigraphic base upon which to build a biochronology of hipparionine horses that has potential regional importance in ordering faunas of Vallesian and Turolian age in other areas of the Old World. This, as well as faunal and radiometric analysis of the Maragheh sequence, is compared with those aspects of other districts. The radiometric age of the so-called «Hipparion Datum» is 12 Ma, if not slightly older, and more than one species of «Hipparion» may be associated with it. Based on cranial morphology, hipparionine horses of Vallesian age consist of a single group; faunas of Turolian age contain four hipparionine groups by these criteria. A group composed of Hipparion prostylum and later members appears to be the most useful in compiling a possible biochronology. This group may have had an endemic European rather than allochthonous (American) origin. Based on the various assessments discussed here the following temporal sequence of certain faunal localities is proposed (oldest to youngest): Vallesian-Höwenegg (Germany), Bou Hanifia I (N. Africa) and Hostalets de Pierola (Spain). Early Turolian-Kopran, Lower Maragheh (Iran). Medial Turolian-Mont Luberon (France), Kerjabad or Ketschawa, Middle Maragheh (Iran), Saloniki (Macedonia), Pikermi (Greece), Shol'avand, Upper Maragheh (Iran), Samos (Greece). Our assessment of the age of the Mont Luberon and Samos faunas differs from conventional assignments.  相似文献   

12.
A hominid upper premolar was discovered in the Azmaka quarry, near Chirpan (Bulgaria). The associated fauna, especially the co-occurrence of Choerolophodon and Anancus among the proboscideans, and Cremohipparion matthewi and Hippotherium brachypus among the hipparions, constrains the age of the locality to the second half of the middle Turolian (ca. 7 Ma), making it the latest pre-human hominid of continental Europe and Asia Minor. The available morphological and metric data are more similar to those of Ouranopithecus from the Vallesian of Greece than to those of the early to middle Turolian hominids of Turkey and Georgia, but the time gap speaks against a direct phyletic link, and Turolian migration from the east cannot be rejected.  相似文献   

13.
The abundant Late Miocene proboscidean remains of Greece have never been studied in detail and compared with those of Eurasia in order to determine their taxonomy and their biostratigraphical and palaeoecological significance. The first results of such study are given in this article. During the past decades, several new proboscidean specimens have been added to the old collections, significantly enriching the available material. The Axios Valley (Macedonia, Greece) proboscidean fossils belong mainly to two species of Choerolophodon: C. anatolicus of early Vallesian age and C. pentelici of late Vallesian–Turolian age. Deinotherium giganteum is rare and recognized only in the late Vallesian locality Ravin de la Pluie of Axios Valley. A zygodont form has also been identified in the Turolian of Axios Valley, attributed to “Mammut” sp. The Late Miocene localities of Nikiti (Macedonia, Greece) revealed several remains of C. pentelici, which are similar to the Turolian ones of Axios Valley. The Samos proboscidean collection includes C. pentelici, “Tetralophodonatticus, “Mammut” sp. and Deinotherium gigantissimum. The taxonomy of the Late Miocene peri-Mediterranean Choerolophodon is given, and the biostratigraphy and palaeoecology of the Greek Late Miocene proboscideans are discussed.  相似文献   

14.
《Geobios》2016,49(6):423-431
Recent works on feeding habits of ungulates, isotopic composition of equid tooth enamel, and phytoliths from late Miocene localities of northern Greece suggested the presence of savannah and excluded dense forests. Furthermore, Mediterranean-like climates were advocated for the late Miocene of Greece. Here, I compare palaeoenvironments inferred for two mammal localities from Chalkidiki and the Axios Valley (Nikiti, upper Vallesian and lower Turolian; Dytiko, upper Turolian) with evidence from contemporaneous plant assemblages from adjacent areas in Greece and Bulgaria. I use vegetation units inferred from pollen and spore, fruit and seed, and leaf assemblages and compare them with the vegetation inferred from mammal and phytolith data. Open vegetation as inferred from mammal and phytolith data is also part of the range of vegetation units discovered from the pollen and spore, seed and fruit, and leaf record (here called the palaeobotanical record). Poaceae are consistently present in late Vallesian to late Turolian pollen records of northern Greece. Further, a number of vegetation units are indicative of forest vegetation ranging from lowland to upland forests dominated by woody angiosperms and mixed coniferous-angiosperm forests. The presence of such forests is not in conflict with the results from mammal and phytolith studies, but it broadens the view on landscapes present in the late Miocene of northern Greece. In addition to a generalized vegetation type commonly inferred by mammal studies, the palaeobotanical record demonstrates the presence of various complementary vegetation types. A comprehensive view on late Miocene landscapes in northern Greece shows that there is no conflict in inferring open herb dominated landscapes and light to dense forests and provides new opportunities for the ecological interpretation of late Miocene ungulates.  相似文献   

15.
The Spanish material of Alicornops simorrense constitutes the best representation of the species in Western Europe. It provides interesting data on the metrical and morphological intraspecific variation of A. simorrense and its evolutionary trends from late Middle Miocene to the early Late Miocene. From late Aragonian to early Vallesian, a slight increase in size is observed, but without clear limits among series. During the late Vallesian, A. simorrense evolved in central Spanish basins into a second species, A. alfambrense, greater in size and with more robust proportions. In the Vallés-Penedés basin, A. simorrense shows a noticeable increase in size, while maintaining its proportions, during the Vallesian. A. simorrense was a very abundant species, an open woodland dweller, with gregarious behaviour, whose extinction was probably linked to the climatic change that took place at the end of the Vallesian and the beginning of the Turolian.  相似文献   

16.
猪类对比研究表明,从晚中新世初期到晚中新世末(或上新世初期),中国与欧洲的古气候、古环境和猪类演化都受到了全球性自然变化的影响,有着相同或相似的发展经历。晚中新世早期(early Vallesian(MN9))中国与欧洲的猪类显示它们均受到先前来自南亚猪类的影响,南亚猪类可能通过东南亚扩散到中国南方,通过西亚扩散到欧洲。晚中新世中期(lateVallesian(MN10)and early Turolian(MN11)),中国和欧洲的猪类与南亚已基本没有交流,在各自地区相对独立地演化发展。晚中新世晚期(late Turolian(MN12、MN13))中国北方除了保留有从南方迁移来的种类外,欧洲的猪类也已出现,此时中国(北方)动物群与欧洲动物群关系较为密切。南亚动物群在晚中新世早期(或者更早些)似乎已经和中国及欧洲的动物群分离。受青藏高原隆升等自然因素的影响,晚中新世中后期中国南方的古环境有一个从较为封闭、湿热的森林类型向相对开阔、干冷稀树草原类型的演变过程,而在此期间北方的自然环境则可能是从早期的半干旱疏林草原逐步发展到晚中新世末期的湿润林地。晚中新世欧洲自然环境有一个与中国南方相似的变化过程,比较而言,晚中新世中后期欧洲的环境可能比中国北方更为开阔和干冷。古气候和古环境变化是影响晚中新世猪类分布演化的决定性因素。  相似文献   

17.
P.Y. Sondaar 《Geobios》1974,7(4):289-306
A revision is given of the Rhone valley Hipparion. One new species is described from Montredon. It is noted that in the lower Vallesian localities one big heavily built Hipparion is present. In the late Vallesian a medium sized Hipparion with short limbs is found; in the Turolian a slender form of medium size and perhaps also a heavy form is present; finally in the Ruscinian two forms are found of which one has a very big size and has cabaloid characteristics.Some remarks are made about the paleoecology of Hipparion in general.  相似文献   

18.
19.
We investigate resource and habitat use by apex predators through stable isotope analysis at two Spanish Late Miocene localities: Los Valles de Fuentidueña (~9.6 Ma, LVF) and Cerro de los Batallones (~9.1 Ma, BAT). The temporal window represented by LVF and BAT was crucial in the shaping of the current Iberian mammalian structure because it corresponds to the initial stages of a faunal turnover episode and regional environmental change at ~9.5–8.5 Ma (Vallesian–Turolian transition), associated with an increase in the seasonality of precipitation. Herbivore and carnivore δ13C and δ18O values do not point to significant changes in either the vegetation cover (a woodland to mesic C3 grassland) or the hydrological regime during the time lapse represented between LVF and BAT. This suggests that the environmental shift recorded around the Vallesian–Turolian boundary may have occurred later in time, since LVF and BAT ages are synchronic with the onset of the turnover event. From the standpoint of predator–prey evaluation by means of stable isotope analysis, statistical post hoc tests, mixing model output, and the assessment of niche occupation by LVF and BAT carnivores point to high levels of interspecific competition among large active carnivores, albeit some genera, such as the amphicyonid Magericyon and specially the hyaenid Lycyaena, seemed to avoid competition by taking prey from a more open habitat. Despite the drop in diversity and change in faunal components observed between the LVF and BAT assemblages, a high degree of resource and habitat competition is evident from stable isotope data.  相似文献   

20.
Abstract: A systematic revision of the sabre‐toothed cat genus Paramachaerodus  Pilgrim, 1913 is presented. Two species are recognized within Paramachaerodus, Pa. orientalis, and Pa. maximiliani, and the genus Promegantereon  Kretzoi, 1938 is retrieved to include Promegantereon ogygia. Material from the Turolian Spanish localities of Crevillente‐2 (MN 11, Alicante) and Las Casiones (MN 13, Teruel), which was previously assigned to Paramachaerodus, is now included in the tribe Metailurini. The exceptional discoveries at the Spanish Vallesian (MN 10, Madrid) fossil site of Batallones‐1 have made it possible to characterize the dentition and cranial anatomy of a previously very poorly known machairodontine cat, formerly included in Paramachaerodus as Pa. ogygia, which now can be distinguished from Pa. orientalis and Pa. maximiliani by the following features: canines without crenulations, P3 with a marked disto‐lingual expansion, P4 without ectostyle and with a well‐developed protocone, M1 bucco‐lingually elongated and double‐rooted, m1 with a larger talonid, and primitive mandible morphology. Thus, the population from Batallones‐1 constitutes a clearly different form from the genus Paramachaerodus, and we propose its inclusion in the genus Promegantereon  Kretzoi, 1938 , together with an upper canine from Crevillente‐2 (MN 11), very similar to those from Batallones‐1. In contrast, Pa. orientalis shows the following apomorphies: crenulated canines, P3 reduced in size and without disto‐lingual expansion, P4 with a clear ectostyle as well as a reduced, backwardly displaced protocone and with a rounded and single‐rooted M1. The species Pa. maximiliani is characterized by its slightly larger size, crenulated canines, very elongated P3 with a moderate disto‐lingual expansion and P4 and M1 similar to those of Pa. orientalis. Paramachaerodus orientalis is recorded at Puente Minero (MN 11, Teruel), Concud (MN 12, Teruel), Crevillente‐15, and Crevillente‐16 (both MN 12, Alicante), and Paramachaerodus maximiliani in Venta del Moro (MN 13, Valencia). The available data suggest that Pr. ogygia was present in the Iberian Late Vallesian and Early Turolian faunas (MN 10 and MN 11) but disappeared after that age. Paramachaerodus was present in the faunas throughout the Turolian, with the species Pa. orientalis and Pa. maximiliani, this latter being probably part of the same immigration event that occurred in the Late Turolian and involved other mammal taxa such as camelids and ursids.  相似文献   

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