Nikita V. Zelenkov (2016)
The first fossil parrot (Aves, Psittaciformes) from Siberia and its implications for the historical biogeography of Psittaciformes.
Biology Letters 12: 20160717
DOI: 10.1098/rsbl.2016.0717
Free pdf:
Modern parrots (crown Psittaciformes) are a species-rich group of mostly tropical and subtropical birds with a very limited fossil record. A partial tarsometatarsus from the late Early Miocene of Siberia (Baikal Lake) is the first pre-Quaternary find of crown Psittaciformes in Asia (and Siberia in particular) and is also the northern-most find of this bird order worldwide. This find documents a broad geographical distribution of parrots during the warmest phase of the Miocene (the so-called ‘Miocene Climatic Optimum’), which has implications for the historical biogeography of Psittaciformes. The presence of parrots on both sides of the Pacific Ocean at the end of the Early Miocene implies a (most probably eastwards) trans-Beringian dispersal which likely took place about 16–18 Ma. The broad Eurasian distribution of parrots in the past further supports a hypothesis that ancestors of modern genera Coracopsis and Agapornis could reach Africa from Eurasia.
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Hanneke J. M. Meijer, Marco Pavia, Joan Madurell-Malapeira & David M. Alba (2016)
A revision of fossil eagle owls (Aves: Strigiformes: Bubo) from Europe and the description of a new species, Bubo ibericus, from Cal Guardiola (NE Iberian Peninsula).
Historical Biology (advance online publication)
The European fossil record of eagle owls, genus Bubo Duméril 1806, is thought to extend back into the Miocene, but records of Bubo before the Middle Pleistocene are scarce and mainly constituted by non-diagnostic or fragmentary specimens. Apart from a number of fossil species of Bubo of uncertain validity, i.e. Bubo? florianae Kretzoi 1957 , Bubo lignitum Giebel 1860 , and Bubo perpastus (Ballman 1976), most fossil Bubo material is unassigned to species or assigned to the extant Bubo bubo (Linnaeus 1758) on the basis of size, especially for Early Pleistocene records. Given the ambiguity about the validity of the earliest records, here we revise the pre-Middle Pleistocene fossil record of Bubo in Europe. Our results indicate that, in Europe, Bubo is first recorded in the Late Pliocene/Early Pleistocene of Italy. By the Early Pleistocene, three taxa can be distinguished: Bubo ibericus sp. nov. from Cal Guardiola (Spain), Bubo sp. nov. indet. from Soave Cava Sud (Italy) and Bubo sp. from various sites across Europe. By the Middle Pleistocene, Eurasian environments experienced a substantial increase in severity and duration of glacial periods which might have led to the replacement of extinct species of Bubo by the recent B. bubo and Bubo scandiacus.
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Robert G. Moyle, Carl H. Oliveros, Michael J. Andersen, Peter A. Hosner, Brett W. Benz, Joseph D. Manthey, Scott L. Travers, Rafe M. Brown & Brant C. Faircloth (2016)
Tectonic collision and uplift of Wallacea triggered the global songbird radiation.
Nature Communications 7: 12709 (2016)
doi: 10.1038/ncomms12709
Songbirds (oscine passerines) are the most species-rich and cosmopolitan bird group, comprising almost half of global avian diversity. Songbirds originated in Australia, but the evolutionary trajectory from a single species in an isolated continent to worldwide proliferation is poorly understood. Here, we combine the first comprehensive genome-scale DNA sequence data set for songbirds, fossil-based time calibrations, and geologically informed biogeographic reconstructions to provide a well-supported evolutionary hypothesis for the group. We show that songbird diversification began in the Oligocene, but accelerated in the early Miocene, at approximately half the age of most previous estimates. This burst of diversification occurred coincident with extensive island formation in Wallacea, which provided the first dispersal corridor out of Australia, and resulted in independent waves of songbird expansion through Asia to the rest of the globe. Our results reconcile songbird evolution with Earth history and link a major radiation of terrestrial biodiversity to early diversification within an isolated Australian continent.
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Palaeoamyda new genus
Edwin Cadena (2016)
Palaeoamyda messeliana nov. comb. (Testudines, Pan-Trionychidae) from the Eocene Messel Pit and Geiseltal localities, Germany, taxonomic and phylogenetic insights.
PeerJ 4:e2647
Background
Abundant pan-trionychid (soft-shell) turtles specimens have been found in Eocene sequences of central Europe, particularly from two localities in Germany, the Messel Pit (a UNESCO World Natural Heritage Site) and Geiseltal, traditionally attributed to Trionyx messelianus or Rafetoides austriacus. Over the last two decades new specimens of this taxon from these two localities have been discovered and fully prepared. However, they have remained unstudied, as well as their phylogenetic position inside Pan-Trionychidae is unknown.
Results
Five new specimens of Palaeoamyda messeliana nov. comb. from Messel Pit and Geiseltal localities are fully described here. A revised diagnosis for the species is also presented here, together with its inclusion in a phylogenetic analysis of Pan-Trionychidae that shows that this species is sister to the extant Amyda cartilaginea, one of the most abundant pan-trionychid (soft-shell) turtles from Asia, both members of the clade Chitrini. The specimens described in here are among the best and most complete fossil pan-trionychid skeletons so far known.
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Guilherme Hermanson, Gabriel S. Ferreira & Max C. Langer (2016)
The largest Cretaceous podocnemidoid turtle (Pleurodira) revealed by an isolated plate from the Bauru Basin, south-central Brazil.
Historical Biology (advance online publication)
The Bauru Basin (south-central Brazil) fossils have largely contributed to understand the faunal composition of South American Cretaceous. Among those, several turtle specimens were retrieved from those deposits, all belonging to Podocnemidoidae, the single group known from the Basin. On the other hand, only incomplete shell elements indicate large turtles such as ‘Peirópolis A’. Another shell fragment, a large peripheral plate from the Marília Formation, is described here. Its lack of surface ornamentation, and deep sulci are generally typical for podocnemidoids. The plate exhibits a narrow knob slightly projected onto the pleuro-marginal sulcus, absent in any other Bauru Basin turtle. According to extant and fossil podocnemidoids measures, we estimated this individual reached 1 m of carapace length, exceeding in size all other taxa known from the Basin. This new report reveals a broader size variation among podocnemidoids from the Late Cretaceous of Bauru Basin and a morphological diversity previously unknown for the period, comparable to those of the Amazon Basin today, in which inhabits the largest extant podocnemidoid Podocnemis expansa. Furthermore, the occurrence of such large turtles implies the presence of perennial streams on the northeastern portion of the Bauru Basin during the Maastrichtian and a richer environment than previously thought.
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Denver W. Fowler (2016)
A new correlation of the Cretaceous formations of the Western Interior
of the United States, I: Santonian-Maastrichtian formations and dinosaur
biostratigraphy.
PeerJ Preprints 4:e2554v1
doi: https://doi.org/10.7287/peerj.preprints.2554v1
https://peerj.com/preprints/2554/
Late Cretaceous deposits of the North American Western Interior
represent the best, if not only, opportunity to construct a high-resolution
chronostratigraphic framework within which to conduct continental-scale
geological and paleontological analyses. This is due to the serendipitous
combination of large areas of outcrop, interfingering marine units with
biostratigraphically informative fossils, and a consistent scattering of
radiometric dates due to synorogenic volcanic activity. Accurate correlation is
essential for testing a large number of current geological and paleobiological
hypotheses; however, despite the large amount of data available, many published
correlations suffer from inaccuracies or are simply based on outdated
information.
Here I present a comprehensive high-resolution stratigraphic chart for
terrestrial Late Cretaceous units of North America, combining published
chronostratigraphic, lithostratigraphic, and biostratigraphic data. For the
first time, nearly two hundred 40Ar / 39Ar radiometric dates are recalibrated
to both current standard and decay constant pairings, correcting errors in
previous recalibrations. Revisions to the stratigraphic placement of most units
are slight, but important changes are made to the proposed correlations of the
Aguja and Javelina Formations, Texas, and miscalculations in recently published
analyses are corrected which in particular affects the relative age positions
of the Belly River Group, Alberta; Judith River Group, Montana, Kaiparowits
Formation, Utah, and Fruitland and Kirtland Formations, New Mexico.
This work represents the most extensive and accurate interbasinal
correlation currently available for the North American Western Interior and should
replace all previously published similar works and diagrams.
The stratigraphic ranges of selected dinosaur clades are plotted on
the chronostratigraphic framework, typically forming stacks of short-duration
species which do not overlap stratigraphically with preceding or succeeding
forms. This is the expected pattern which is produced by an anagenetic mode of
evolution, suggesting that true branching (speciation) events were rare and may
have geographic significance. Purported north-south provinciality of dinosaurs
is shown to be mostly an artifact of stratigraphic miscorrelation. Rapid
stepwise acquisition of display characters in many dinosaur clades, in
particular chasmosaurine ceratopsids, suggests that they may represent the
highest resolution biostratigraphic markers to be used where radiometric dates
are not available.
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Shin-ichi Sano & Atsushi Yabe (2016)
Fauna and flora of Early Cretaceous Tetori Group in Central Japan: the clues to revealing the evolution of Cretaceous terrestrial ecosystem in East Asia.
Palaeoworld (advance online publication)
doi: http://dx.doi.org/10.1016/j.palwor.2016.10.004
http://www.sciencedirect.com/science/article/pii/S1871174X16301032
The Early Cretaceous Tetori Group in northern Central Japan was deposited in the eastern margin of the Asian Continent at mid-latitudes. It consists of two depositional stages: DS2 (Berriasian–late Hauterivian; mainly brackish environment with intercalations of marine horizons) and DS3 (Barremian–Aptian; freshwater environments only). Review of their faunal and floral compositions reveals that 1) two vertebrate fossil localities in DS3: Kaseki-kabe (upper part of the Kuwajima Formation) and Kitadani Dinosaur Quarry (Kitadani Formation) are assigned to the Barremian and the Aptian, respectively, and probably coeval to the Jehol Group in the Liaoning, northern China; 2) abundant freshwater bivalves occur in DS3, and the Trigonioides–Plicatounio–Nippononaia (TPN) assemblage is present only in the Kitadani Formation; and 3) stratigraphic change of plant assemblages in DS3 indicates that climatic change (warmer and dryer) occurred around the Barremian–Aptian boundary, which is concordant with the faunal change inferred from the choristodere-bearing assemblage in the Okurodani and Kuwajima formations to the crocodyliform-bearing assemblage in the Kitadani Formation. Vertebrate and invertebrate faunal as well as floral compositions of the Tetori Group are distinct from those of the Jehol Group. Paleoclimatic and/or paleogeographical conditions were probably different between two regions, and thus paleobiogeographical differentiation in East Asia is suggested in the Early Cretaceous.
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Madeleine L. Vickers, Gregory D. Price, Rhodri M. Jerrett, and Matthew Watkinson (2016)
Stratigraphic and geochemical _expression_ of Barremian–Aptian global climate change in Arctic Svalbard.
Geosphere 12: 1594-1605
doi:10.1130/GES01344.1
http://geosphere.gsapubs.org/content/early/2016/08/23/GES01344.1.abstract?rss=1
Significant changes in global climate and carbon cycling occurred during the Early Cretaceous. This study examines the _expression_ of such climatic events in high-latitude Svalbard together with the stratigraphic utility of carbon-isotope stratigraphies. Isotopic analysis of fossil wood fragments (from the Rurikfjellet, Helvetiafjellet, and Carolinefjellet formations, Festningen, Spitsbergen) record a distinctive pattern including a negative isotope excursion preceding a positive event, correlatable with the global early Aptian isotope event. Our carbon-isotope profile improves the stratigraphic correlation and relative dating of the succession. We show that the upper part of the Helvetiafjellet Formation was deposited during the early Aptian, and not the late Barremian, as previously thought. Furthermore, we estimate an age for the abrupt contact of the Rurikfjellet Formation with the overlying Helvetiafjellet Formation (associated with a pulse of igneous activity) to be ca. 129 Ma or ca. 124 Ma, depending on which age model for the Early Cretaceous is used.
The well-known dinosaur footprints of the Helvetiafjellet Formation at Festningen are constrained to the middle Barremian and, coupled with floral data, support a warm late Barremian prior to the Aptian carbon-isotope event. The appearance of glendonites at 655 m in the Carolinefjellet Formation is consistent with global cooling in the late Aptian–early Albian.
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