scholarly journals Phytophagy on fossil ferns from Argentina (Palo Pintado Formation, Late Miocene): a review of their fossil record and ichnotaxonomy

2015 ◽  
Vol 18 (2) ◽  
pp. 225-238 ◽  
Author(s):  
Juan M. Robledo ◽  
Laura C. Sarzetti ◽  
Luisa M. Anzótegui
Keyword(s):  
Late Miocene ◽  
Fossil Record

scholarly journals Unsupervised learning of satellite images enhances discovery of late Miocene fossil sites in the Urema Rift, Gorongosa, Mozambique

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11573
Author(s):  
João d’Oliveira Coelho ◽  
Robert L. Anemone ◽  
Susana Carvalho
Keyword(s):  
Unsupervised Learning ◽  
Late Miocene ◽  
Fossil Record ◽  
Satellite Images ◽  
Near Infrared ◽  
Rift System ◽  
East African Rift System ◽  
Coastal Forests ◽  
Hominin Evolution ◽  
Fossil Site

Background Paleoanthropological research focus still devotes most resources to areas generally known to be fossil rich instead of a strategy that first maps and identifies possible fossil sites in a given region. This leads to the paradoxical task of planning paleontological campaigns without knowing the true extent and likely potential of each fossil site and, hence, how to optimize the investment of time and resources. Yet to answer key questions in hominin evolution, paleoanthropologists must engage in fieldwork that targets substantial temporal and geographical gaps in the fossil record. How can the risk of potentially unsuccessful surveys be minimized, while maximizing the potential for successful surveys? Methods Here we present a simple and effective solution for finding fossil sites based on clustering by unsupervised learning of satellite images with the k-means algorithm and pioneer its testing in the Urema Rift, the southern termination of the East African Rift System (EARS). We focus on a relatively unknown time period critical for understanding African apes and early hominin evolution, the early part of the late Miocene, in an overlooked area of southeastern Africa, in Gorongosa National Park, Mozambique. This clustering approach highlighted priority targets for prospecting that represented only 4.49% of the total area analysed. Results Applying this method, four new fossil sites were discovered in the area, and results show an 85% accuracy in a binary classification. This indicates the high potential of a remote sensing tool for exploratory paleontological surveys by enhancing the discovery of productive fossiliferous deposits. The relative importance of spectral bands for clustering was also determined using the random forest algorithm, and near-infrared was the most important variable for fossil site detection, followed by other infrared variables. Bands in the visible spectrum performed the worst and are not likely indicators of fossil sites. Discussion We show that unsupervised learning is a useful tool for locating new fossil sites in relatively unexplored regions. Additionally, it can be used to target specific gaps in the fossil record and to increase the sample of fossil sites. In Gorongosa, the discovery of the first estuarine coastal forests of the EARS fills an important paleobiogeographic gap of Africa. These new sites will be key for testing hypotheses of primate evolution in such environmental settings.

Spatiotemporal palaeodiversity patterns of modern crocodiles (Crocodyliformes: Eusuchia)

2019 ◽  
Vol 189 (2) ◽  
pp. 635-656 ◽  
Author(s):  
Ane De Celis ◽  
Iván Narváez ◽  
Francisco Ortega
Keyword(s):  
South America ◽  
Least Squares ◽  
Late Miocene ◽  
North American ◽  
Fossil Record ◽  
Generalized Least Squares ◽  
Global Scale ◽  
Biotic Factors ◽  
Species Dynamics ◽  
Over Time

Abstract Eusuchia is a crocodyliform clade with a rich and diverse fossil record dating back to the Mesozoic. There are several recent studies that analyse crocodyliform palaeodiversity over time, but none of them focuses exclusively on eusuchians. Thus, we estimated subsampled eusuchian palaeodiversity species dynamics over time not only at a global scale, but also by continents and main crocodylian lineages (Alligatoroidea, Crocodyloidea and Gavialoidea). These estimates reveal complex spatiotemporal palaeodiversity patterns, in which two maxima can be detected: the first during the Palaeocene and the second, which is also the biggest, in the middle-late Miocene. The Palaeocene shift is related to a North American alligatoroid diversification, whereas the middle–late Miocene maximum is related to a diversification of the three main Crocodylia lineages in Gondwanan land masses, but especially in South America. Additionally, a model-based study using generalized least squares was carried out to analyse the relationships between different abiotic and sampling proxies and eusuchian palaeodiversity. The results show that palaeotemperature is the most important factor amongst the analysed proxies, in accordance with previous studies. However, the results suggest that, along with palaeotemperature, other abiotic and/or biotic factors might also be driving eusuchian palaeodiversity dynamics.

scholarly journals The first Miocene fossils of Lacerta cf.trilineata(Squamata, Lacertidae) with a comparative study of the main cranial osteological differences in green lizards and their relatives

2019 ◽  
Author(s):  
Andrej Čerňanský ◽  
Elena V. Syromyatnikova
Keyword(s):  
Comparative Study ◽  
Late Miocene ◽  
Fossil Record ◽  
Calibration Point ◽  
Lizard Species ◽  
Podarcis Muralis ◽  
Modern Species ◽  
Zootoca Vivipara ◽  
Morphological Differences ◽  
Important Evidence

AbstractWe here describe the first fossil remains of a green lizardof theLacertagroup from the late Miocene (MN 13) of the Solnechnodolsk locality in southern European Russia. This region of Europe is crucial for our understanding of the paleobiogeography and evolution of these middle-sized lizards. Although this clade has a broad geographical distribution across the continent today, its presence in the fossil record has only rarely been reported. In contrast to that, the material described here is abundant, consists of a premaxilla, maxillae, frontals, parietals, jugals, quadrate, pterygoids, dentaries and vertebrae. The comparison of these elements to all extant green lizard species shows that these fossils are indistinguishable fromLacerta trilineata. Thus, they form the first potential evidence of the occurrence of this species in the Miocene. This may be also used as a potential calibration point for further studies. Together with other lizard fossils, Solnechnodolsk shows an interesting combination of survivors and the dawn of modern species. This locality provides important evidence for the transition of an archaic Miocene world to the modern diversity of lizards in Europe. In addition, this article represents a contribution to the knowledge of the comparative osteological anatomy of the selected cranial elements in lacertid. This study gives special emphasis to the green lizards, but new data are also presented for related taxa, e.g.,Timon lepidus, Podarcis muralisorZootoca vivipara. Although the green lizards include several cryptic species for which determination based on isolated osteological material would be expected to be difficult, our comparisons show several important morphological differences.

scholarly journals A skull of a very large crane from the late Miocene of Southern Germany, with notes on the phylogenetic interrelationships of extant Gruinae

2020 ◽  
Vol 161 (4) ◽  
pp. 923-933
Author(s):  
Gerald Mayr ◽  
Thomas Lechner ◽  
Madelaine Böhme
Keyword(s):  
Late Miocene ◽  
Fossil Record ◽  
Morphological Characteristics ◽  
Southern Germany ◽  
Siberian Crane ◽  
Large Size ◽  
Early Late

Abstract We describe a partial skull of a very large crane from the early late Miocene (Tortonian) hominid locality Hammerschmiede in southern Germany, which is the oldest fossil record of the Gruinae (true cranes). The fossil exhibits an unusual preservation in that only the dorsal portions of the neurocranium and beak are preserved. Even though it is, therefore, very fragmentary, two morphological characteristics are striking and of paleobiological significance: its large size and the very long beak. The fossil is from a species the size of the largest extant cranes and represents the earliest record of a large-sized crane in Europe. Overall, the specimen resembles the skull of the extant, very long-beaked Siberian Crane, Leucogeranus leucogeranus, but its affinities within Gruinae cannot be determined owing to the incomplete preservation. Judging from its size, the fossil may possibly belong to the very large “Grus” pentelici, which stems from temporally and geographically proximate sites. The long beak of the Hammerschmiede crane conforms to an open freshwater paleohabitat, which prevailed at the locality.

scholarly journals The First Appearance of Hucho (Salmonidae) in the Fossil Record of Eastern Europe

2015 ◽  
Vol 49 (5) ◽  
pp. 413-420 ◽  
Author(s):  
О. М. Kovalchuk
Keyword(s):  
Eastern Europe ◽  
Late Pleistocene ◽  
Late Miocene ◽  
Fossil Record ◽  
Middle Miocene ◽  
Fossil Remains ◽  
Extant Genus ◽  
Geological Past ◽  
Late Neogene ◽  
Southern Ukraine

Until now, fossil remains of Hucho Gunther, 1866 are known only from the Oligocene - middle Miocene strata of Baikal Russia, and from the late Pleistocene of Germany. New specimens, now identified as Hucho sp., come from the late Miocene of southern Ukraine. Numerous fragments of opercular bones and jaw teeth, morphologically similar to those in the extant genus Hucho, were found in Kubanka 2, Cherevychnoe 3, Tretya Krucha localities and dated by the late Sarmatian - early Maeotian (10-8 Ma). Th ese remains document the first appearance of huchen in geological past of Europe, filling in gap in distribution of this genus during the late Neogene, and throw light upon its biogeographical history.

scholarly journals Palaemon monsdamarum n. sp. (Crustacea, Decapoda, Palaemonidae) from the late Miocene of Mondaino (Rimini, Emilia-Romagna, Italy)

2017 ◽  
Author(s):  
Giovanni Pasini ◽  
Alessandro Garassino
Keyword(s):  
Late Miocene ◽  
Fossil Record ◽  
First Report ◽  
Upper Miocene

We report Palaemon monsdamarum n. sp. (Crustacea, Decapoda, Palaemonidae) from the tripoli of the Messinian (upper Miocene) of Mondaino (Rimini, Emilia-Romagna, Italy). The presence of a new caridean species expands the scarce knowledge on the distribution and environmental range for the genus, usually scarcely reported in the worldwide Cenozoic fossil record. This is the first report of a carideans from the Miocene of Italy.

scholarly journals Late Miocene chondrichthyans from Lago Bayano, Panama: Functional diversity, environment and biogeography

2017 ◽  
Vol 91 (3) ◽  
pp. 512-547 ◽  
Author(s):  
Victor J. Perez ◽  
Catalina Pimiento ◽  
Austin Hendy ◽  
Gerardo González-Barba ◽  
Gordon Hubbell ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Functional Diversity ◽  
Late Miocene ◽  
Fossil Record ◽  
Marine Mammals ◽  
Probabilistic Approach ◽  
Generalist Species ◽  
The Pacific ◽  
Wide Range

AbstractThis newly described chondrichthyan fauna from the late Miocene Chucunaque Formation of Lago Bayano reveals a prolific and highly diverse assemblage from Panama, and one of the richest shark faunas from the Neotropics. Strontium geochronology indicates an age of 10–9.5 Ma for the chonrichthyan-bearing strata. Field efforts resulted in 1429 identifiable specimens comprising at least 31 taxa, of which at least eight are new to the documented fossil record of Panama. With this information an analysis of functional diversity was conducted, indicating ecosystems dominated by generalist species feeding upon a wide range of organisms, from plankton to marine mammals. A probabilistic approach of paleobathymetric estimation suggests a neritic environment. Previous studies based on foraminifera have suggested that the Chucunaque Formation had a greater Pacific Ocean affinity, making this the first Miocene chondrichthyan fauna described from the Pacific shelf of Panama. However, our geographic comparisons show that this fauna has mixed Caribbean and Pacific biogeographic affinities, which likely supports the previously purported connection between chondrichthyan faunas during the late Miocene.

Colonization of the ancient southern oceans by small-sized Phocidae: new evidence from Australia

2020 ◽  
Author(s):  
James P Rule ◽  
Justin W Adams ◽  
Erich M G Fitzgerald
Keyword(s):  
Energy Efficiency ◽  
Southern Ocean ◽  
Late Miocene ◽  
Fossil Record ◽  
Trophic Levels ◽  
Food Chains ◽  
Early Pliocene ◽  
Sea Lions ◽  
Fur Seals ◽  
New Evidence

Abstract Most of the diversity of extant southern true seals (Phocidae: Monachinae) is present in the Southern Ocean, but a poor fossil record means that the origin of this fauna remains unknown. Australia represents a large gap in the record bordering the Southern Ocean that could possibly inform on the origins of the extant Antarctic monachines, with most known fossils remaining undescribed. Here we describe the oldest Australian fossil pinniped assemblage, from the Late Miocene to the Early Pliocene of Beaumaris. Two fossils are referrable to Pinnipedia, five (possibly six) to Phocidae and a humerus is referrable to Monachinae. The humerus is not referrable to any extant tribe, potentially representing an archaic monachine. The description of this assemblage is consistent with the Neogene pinniped fauna of Australia being exclusively monachine before the arrival of otariids (fur seals and sea lions). The Beaumaris humerus, along with other Neogene phocids from the Southern Ocean margins, were smaller than their extant Antarctic relatives, possibly driven by longer food chains with less energy efficiency between trophic levels. This suggests that small archaic phocids potentially used the Southern Ocean as a means of dispersal before the arrival of extant Antarctic monachines.

The earliest member of Neocricetodon (Rodentia: Cricetidae): a redescription of N. moldavicus from Eastern Europe, and its bearing on the evolution of the genus

2016 ◽  
Vol 90 (4) ◽  
pp. 771-784 ◽  
Author(s):  
Maxim V. Sinitsa ◽  
Andrian Delinschi
Keyword(s):  
Phylogenetic Analysis ◽  
Eastern Europe ◽  
Late Miocene ◽  
Fossil Record ◽  
Type Material ◽  
Dental Morphology ◽  
Eastern European ◽  
European Origin ◽  
Geological Age ◽  
Early Late

AbstractThe genus Neocricetodon represents one of the most diverse radiations of extinct cricetines. Its early evolution remains unclear, mainly owing to the incomplete fossil record. One of the earliest and least known species of this genus is N. moldavicus described from the early late Miocene localities Bujor 1 and Calfa, Moldova. We reexamined the type material of this species and compared it with other species of Neocricetodon. Despite its old geological age, N. moldavicus demonstrates rather advanced dental morphology including the anterocone of M1 being deeply split; mesolophs and mesolophids partially reduced; and the labial spur of the anterolophule, ectomesolophids, and lingual anterolophid of m2 lacking. The phylogenetic analysis of 15 Neocricetodon species based on 22 dental characters revealed three synapomorphies for the genus: presence of the M1 labial anterolophule, the four-rooted M2, and presence of the labial anterolophulid of m1. “Kowalskia cf. schaubi” from Rudabánya and “Kowalskia sp.” from Vösendorf, formerly considered as the earliest finds of Neocricetodon, do not possess these characters and rather represent the genus Democricetodon. Our study also suggests that Kowalskia complicidens is a member of Sinocricetus, and that N. neimengensis and N. zhengi are junior synonyms of N. polonicus. The recognition of N. moldavicus as the earliest member of the genus within the clade containing the species of Neocricetodon from France and Spain supports the hypothesis of the Eastern European origin of the Western European Neocricetodon species.

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