[dinosaur] Turkey ribcage + early mammal jaws + whale gigantism + Cretaceous feather-eating bugs + more

Ben Creisler
[email protected]


Some recent non-dino papers:

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Robert J. Brocklehurst, Sabine Moritz, Jonathan Codd, William I. Sellers &
Elizabeth L. Brainerd (2019)
XROMM kinematics of ventilation in wild turkeys (Meleagris gallopavo).
Journal of Experimental Biology 222: jeb209783
doi: 10.1242/jeb.209783
https://urldefense.proofpoint.com/v2/url?u=https-3A__jeb.biologists.org_content_222_23_jeb209783&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=xXhJb2SlRL_6yhE29p6ZiPGcqroyxuIkGUcNGX6E0mo&e= 

The avian ribcage is derived relative to other amniotes, and is
hypothesised to be constrained in its movements during ventilation. The
double-headed ribs form two articulations with the vertebrae, and are
thought to rotate about a strict anatomical axis. However, this
costovertebral joint constraint has not been demonstrated empirically and
was not found in other taxa with double-headed ribs (i.e. crocodilians).
Here, we used X-ray reconstruction of moving morphology (XROMM) to quantify
rib rotation in wild turkeys (Meleagris gallopavo) during breathing. We
demonstrate that, as predicted from anatomy, the ribs do rotate in a
hinge-like manner about a single axis. There is also evidence for
elliptical motion of the sternum, as has been reported in other taxa. The
evolution of the avian ribcage is closely related to the co-evolution of
ventilation and flight, and these results are important for how we model
ventilation mechanics in living and fossil birds.

===========


Juan Alberto Pérez-Valera, Mélani Berrocal-Casero & Fernando Pérez-Valera
(2019)
First Triassic tetrapod (Eusauropterygia) in the Triassic of the Subbetic
domain of the Betic Cordillera (Southeastern Spain).
PalZ (advance online publication)
DOI: https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1007_s12542-2D019-2D00500-2Dy&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=IvM0H58Sf5MtGce2he1ij4EDl86k4s-dg5BoVBCOKRM&e= 
https://urldefense.proofpoint.com/v2/url?u=https-3A__link.springer.com_article_10.1007_s12542-2D019-2D00500-2Dy&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=peDhakWsWgX0xfZcVPq3meRUA2yFMzj8j-wpTChlXvE&e= 


Sauropterygian vertebrate remains from the Ladinian (Middle Triassic) of
the proximity of Calasparra (Murcia, Spain) are described here. They
represent the first documented Triassic vertebrate remains found in the
Province of Murcia, and the first in the Subbetic domain of the Betic
Cordillera (Southeastern Spain). These new remains consist of incomplete
vertebrae, some fragmented neural spine apophyses, fragments of transverse
processes, a partial thoracic vertebrae mould and one isolated thoracic
vertebral centrum, seemingly of a single specimen. Their features permit to
refer them to the suborder Eusauropterygia. These fossils have been found
in the middle part of the upper member of the Cehegín Formation. The
biostratigraphical framework of the Cehegín Formation consists of a
relatively abundant fossil content that allowed its attribution to the
uppermost Fassanian (Lower Ladinian). The sedimentary features and the
palaeontological content of the site are typical of an epicontinental
platform.

===

Free pdf:

Andrej ČERŇANSKÝ & Marc Louis AUGÉ (2019)
The Oligocene and Miocene fossil lizards (Reptilia, Squamata) of Central
Mongolia.
GEODIVERSITAS 41 (24): 811-839
DOI: https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.5252_geodiversitas2019v41a24&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=wcN4VhQpnhHhEBoh5JWpGgXn96x2knvMRRDFABHNv3s&e= 
https://urldefense.proofpoint.com/v2/url?u=http-3A__sciencepress.mnhn.fr_en_periodiques_geodiversitas_41_24&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=9CpIGDfNlSuBDWVgcuA2qL21ypCPCsW83IP5GNhpXgI&e= 

Free pdf:
https://urldefense.proofpoint.com/v2/url?u=http-3A__sciencepress.mnhn.fr_sites_default_files_articles_pdf_g2019v41a24.pdf&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=fmtL2TzFej0izuWhF3uNViWFgjGbfP8VaB-qXT3fn4k&e= 


Lizard material from the early Oligocene and early and late Miocene of the
Valley of Lakes, Central Mongolia is described. Besides the Oligocene
fossorial squamate published elsewere, the material can be allocated to
several major clades: Agamidae, Lacertidae and Anguidae (Glyptosaurinae).
The presence of Pseudotinosaurus Alifanov, 1991 in early and late Rupelian
localities shows that this taxon has a continuous history in this area from
the Eocene to the Oligocene. The same is true for the clade Glyptosaurinae,
represented by isolated osteoderms in the early Oligocene locality Hsanda
Gol. This might suggest that the Eocene-Oligocene transition did not have
such a strong or rapid impact in East Asia, in contrast to the Grande
Coupure in Europe, at least among some lizard clades. The early Oligocene
(early Rupelian) lacertids from Taatsiin Gol, Hsanda Gol and Tatal Gol
represent one of the oldest evidences of Asiatic dispersal of this clade.
It might reflect the dispersal pathways after closure of the Turgai Strait
between Europe and Asia. Some of the material closely resembles the common
European Oligocene taxon Lacerta s.l. filholi Augé, 1988. In the early
Miocene locality Olon Ovoony Khurem, two clades can be recognized –
Lacertidae and a scincoid with a specialized dentition (family
indeterminate). The clade Lacertidae forms a dominant component of the late
Miocene lizard fossils in Mongolia. The material from the locality Builstyn
Khudag shows differences compared to the early Miocene lacertids and
represents the oldest evidence of the tribe Eremiadini in this area.

=====

Free pdf:

Nuria Melisa Morales-García, Thomas D. Burgess, Jennifer J. Hill, Pamela G.
Gill and Emily J. Rayfield (2019)
The use of extruded finite-element models as a novel alternative to
tomography-based models: a case study using early mammal jaws.
Journal of the Royal Society Interface 16: 20190674
doi: https://urldefense.proofpoint.com/v2/url?u=http-3A__dx.doi.org_10.1098_rsif.2019.0674&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=Maoiw69eKgGtfT1kgQM0PjLP54soJRfiKEeoEHKeIsc&e= 
https://urldefense.proofpoint.com/v2/url?u=https-3A__royalsocietypublishing.org_doi_10.1098_rsif.2019.0674&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=yPkxRj6knG2-7arJ7eYZZogp3D1u1Yst2oD_ABDdvG8&e= 

Free pdf:
https://urldefense.proofpoint.com/v2/url?u=https-3A__royalsocietypublishing.org_doi_pdf_10.1098_rsif.2019.0674&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=reZqR_Wh7Z5_BITDVRtRhfMqJP2uQDLmbcz45nOrDsc&e= 

Finite-element (FE) analysis has been used in palaeobiology to assess the
mechanical performance of the jaw. It uses two types of models:
tomography-based three-dimensional (3D) models (very accurate, not always
accessible) and two-dimensional (2D) models (quick and easy to build, good
for broad-scale studies, cannot obtain absolute stress and strain values).
Here, we introduce extruded FE models, which provide fairly accurate
mechanical performance results, while remaining low-cost, quick and easy to
build. These are simplified 3D models built from lateral outlines of a
relatively flat jaw and extruded to its average width. There are two types:
extruded (flat mediolaterally) and enhanced extruded (accounts for width
differences in the ascending ramus). Here, we compare mechanical
performance values resulting from four types of FE models (i.e.
tomography-based 3D, extruded, enhanced extruded and 2D) in Morganucodon
and Kuehneotherium. In terms of absolute values, both types of extruded
model perform well in comparison to the tomography-based 3D models, but
enhanced extruded models perform better. In terms of overall patterns, all
models produce similar results. Extruded FE models constitute a viable
alternative to the use of tomography-based 3D models, particularly in
relatively flat bones.

====

J. A. Goldbogen, D. E. Cade, D. M. Wisniewska, J. Potvin, P. S. Segre, M.
S. Savoca, E. L. Hazen, M. F. Czapanskiy, S. R. Kahane-Rapport, S. L.
DeRuiter, S. Gero, P. Tønnesen, W. T. Gough, M. B. Hanson, M. M. Holt, F.
H. Jensen, M. Simon, A. K. Stimpert, P. Arranz, D. W. Johnston, D. P.
Nowacek, S. E. Parks, F. Visser, A. S. Friedlaender, P. L. Tyack, P. T.
Madsen & N. D. Pyenson (2019)
Why whales are big but not bigger: Physiological drivers and ecological
limits in the age of ocean giants.
Science 366(6471): 1367-1372
DOI: 10.1126/science.aax9044
https://urldefense.proofpoint.com/v2/url?u=https-3A__science.sciencemag.org_content_366_6471_1367.abstract&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=-Qgz3H44g_d3asZvcO6Bk-QOQedelOmTsmVy_zz6POc&e= 

It's the prey that matters

Although many people think of dinosaurs as being the largest creatures to
have lived on Earth, the true largest known animal is still here today--the
blue whale. How whales were able to become so large has long been of
interest. Goldbogen et al. used field-collected data on feeding and diving
events across different types of whales to calculate rates of energy gain
(see the Perspective by Williams). They found that increased body size
facilitates increased prey capture. Furthermore, body-size increase in the
marine environment appears to be limited only by prey availability.

Abstract

The largest animals are marine filter feeders, but the underlying mechanism
of their large size remains unexplained. We measured feeding performance
and prey quality to demonstrate how whale gigantism is driven by the
interplay of prey abundance and harvesting mechanisms that increase prey
capture rates and energy intake. The foraging efficiency of toothed whales
that feed on single prey is constrained by the abundance of large prey,
whereas filter-feeding baleen whales seasonally exploit vast swarms of
small prey at high efficiencies. Given temporally and spatially aggregated
prey, filter feeding provides an evolutionary pathway to extremes in body
size that are not available to lineages that must feed on one prey at a
time. Maximum size in filter feeders is likely constrained by prey
availability across space and time.
****
Terrie M. Williams (2019)
The biology of big
Science 366(6471): 1316-1317
DOI: 10.1126/science.aba1128
https://urldefense.proofpoint.com/v2/url?u=https-3A__science.sciencemag.org_content_366_6471_1316&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=9bMwGluAB03qgqOkDsR08nK9BKF1q1pXvKkGQnYY3MU&e= 


Summary

With so many recent scientific advances focused on the mini, micro, nano,
and molecular scales, there is a tendency to overlook the titanic biology
of giants that share the Earth. The sheer magnitude of a scientific
undertaking to study an oceanic, 25-m-long, 95,000-kg wild blue whale
(Balaenoptera musculus)—the largest vertebrate in the animal kingdom—has
long left researchers with little more than brief glimpses of their
presence when the leviathan surfaces to breathe. On page 1367 of this
issue, Goldbogen et al. (1) describe how they took advantage of
developments in microprocessor technology to design submersible wildlife
tags. The authors used the new tools to measure the feeding performance and
prey choices of the largest mammals in the seas. These data revealed the
ecological and evolutionary factors that drive the biology of being, not
just big, but the biggest ever—perhaps the biggest possible.

===

Free pdf:

Taiping Gao, Xiangchu Yin, Chungkun Shih, Alexandr P. Rasnitsyn, Xing Xu,
Sha Chen, Chen Wang & Dong Ren (2019)
New insects feeding on dinosaur feathers in mid-Cretaceous amber.
Nature Communications 10, Article number: 5424
doi: https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1038_s41467-2D019-2D13516-2D4&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=g8WEw5SUWKp6mrR6R5JvN85zIYx9r4oeijv6Uj9SGU4&e= 
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.nature.com_articles_s41467-2D019-2D13516-2D4&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=n-empxuMhnSfw2gSUucJuToRROsr6135haydPU8kl3w&e= 

Free pdf:
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.nature.com_articles_s41467-2D019-2D13516-2D4.pdf&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=gXSHqJIvODK8hOMNMshzYWCdArXJI6palOERGfaIjyQ&e= 

Due to a lack of Mesozoic fossil records, the origins and early evolution
of feather-feeding behaviors by insects are obscure. Here, we report ten
nymph specimens of a new lineage of insect, Mesophthirus engeli gen et. sp.
nov. within Mesophthiridae fam. nov. from the mid-Cretaceous (ca. 100 Mya)
Myanmar (Burmese) amber. This new insect clade shows a series of
ectoparasitic morphological characters such as tiny wingless body, head
with strong chewing mouthparts, robust and short antennae having long
setae, legs with only one single tarsal claw associated with two additional
long setae, etc. Most significantly, these insects are preserved with
partially damaged dinosaur feathers, the damage of which was probably made
by these insects’ integument-feeding behaviors. This finding demonstrates
that feather-feeding behaviors of insects originated at least in
mid-Cretaceous, accompanying the radiation of feathered dinosaurs including
early birds.


News:

https://urldefense.proofpoint.com/v2/url?u=https-3A__phys.org_news_2019-2D12-2Dancient-2Dlice-2Dlike-2Dinsects-2Ddinosaur-2Dfeathers.html&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=WkgbWukhL_4pvUmGCmxzihljj3Oc9O5vQ9T_22VU3dE&e= 

====

Free pdf:

Ekaterina Larina, David J. Bottjer, Frank A. Corsetti, John-Paul Zonneveld,
Aaron J. Celestian & Jake V. Bailey (2019)
Uppermost Triassic phosphorites from Williston Lake, Canada: link to
fluctuating euxinic-anoxic conditions in northeastern Panthalassa before
the end-Triassic mass extinction.
Scientific Reports 9, Article number: 18790
doi: https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1038_s41598-2D019-2D55162-2D2&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=GRkEOur15YBDv4hVpTiPyo79yOFVoaIc5eg6r3r0VAc&e= 
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.nature.com_articles_s41598-2D019-2D55162-2D2&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=Auw0vmDNAIRA7-ngMl8aCoi4gNKJ5Pk_Y0n3ut1vGe0&e= 

Free pdf:
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.nature.com_articles_s41598-2D019-2D55162-2D2.pdf&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=MkI3Xbr_P_2yn5hLvDiLc-wjVegcuPqxvjka0WApOHU&e= 


The end-Triassic mass extinction (ETE) is associated with a rise in CO2 due
to eruptions of the Central Atlantic Magmatic Province (CAMP), and had a
particularly dramatic effect on the Modern Fauna, so an understanding of
the conditions that led to the ETE has relevance to current rising CO2
levels. Here, we report multiple phosphorite deposits in strata that
immediately precede the ETE at Williston Lake, Canada, which allow the
paleoenvironmental conditions leading up to the mass extinction to be
investigated. The predominance of phosphatic coated grains within
phoshorites indicates reworking in shallow water environments. Raman
spectroscopy reveals that the phosphorites contain organic carbon, and
petrographic and scanning electron microscopic analyses reveal that the
phosphorites contain putative microfossils, potentially suggesting
microbial involvement in a direct or indirect way. Thus, we favor a
mechanism of phosphogenesis that involves microbial polyphosphate
metabolism in which phosphatic deposits typically form at the interface of
euxinic/anoxic and oxic conditions. When combined with data from deeper
water deposits (Kennecott Point) far to the southwest, it would appear a
very broad area of northeastern Panthalassa experienced anoxic to euxinic
bottom water conditions in the direct lead up to the end-Triassic mass
extinction. Such a scenario implies expansion and shallowing of the oxygen
minimum zone across a very broad area of northeastern Panthalassa, which
potentially created a stressful environment for benthic metazoan
communities. Studies of the pre-extinction interval from different sites
across the globe are required to resolve the chronology and spatial
distribution of processes that governed before the major environmental
collapse that caused the ETE. Results from this study demonstrate that
fluctuating anoxic and euxinic conditions could have been potentially
responsible for reduced ecosystem stability before the onset of CAMP
volcanism, at least at the regional scale.

===

Free pdf:

L. E. Augland, V. V. Ryabov, V. A. Vernikovsky, S. Planke, A. G. Polozov,
S. Callegaro, D. A. Jerram & H. H. Svensen (2019)
The main pulse of the Siberian Traps expanded in size and composition.
Scientific Reports 9, Article number: 18723
doi: https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1038_s41598-2D019-2D54023-2D2&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=QmcDZ0nn6-LRJoszm620_j1nYLiphoy0ZtPUdyirnH0&e= 
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.nature.com_articles_s41598-2D019-2D54023-2D2&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=wFIoVJw8TaQIMFLQnfk2QB0dh4h5c2cNMDFnr1g82Ws&e= 
Free pdf:
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.nature.com_articles_s41598-2D019-2D54023-2D2.pdf&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=ZIUkZEQXkO_e835qNk3CN1j5NCL6VdpdPfcHNe9GwA8&s=uZmE8NyW5UAPnFmQVvHi0EGWwWp6zJ8P3xEJKnbp_3w&e= 


Emplacement of large volumes of (sub)volcanic rocks during the main pulse
of the Siberian Traps occurred within <1 m.y., coinciding with the
end-Permian mass extinction. Volcanics from outside the main Siberian
Traps, e.g. Taimyr and West Siberia, have since long been correlated, but
existing geochronological data cannot resolve at a precision better than ~5
m.y. whether (sub)volcanic activity in these areas actually occurred during
the main pulse or later. We report the first high precision U-Pb zircon
geochronology from two alkaline ultramafic-felsic layered intrusive
complexes from Taimyr, showing synchronicity between these and the main
Siberian Traps (sub)volcanic pulse, and the presence of a second
Dinerian-Smithian pulse. This is the first documentation of felsic
intrusive magmatism occurring during the main pulse, testifying to the
Siberian Trap’s compositional diversity. Furthermore, the intrusions cut
basal basalts of the Taimyr lava stratigraphy hence providing a minimum age
of these basalts of 251.64 ± 0.11 Ma. Synchronicity of (sub)volcanic
activity between Taimyr and the Siberian Traps imply that the total area of
the Siberian Traps main pulse should include a ~300 000 km2 area north of
Norilsk. The vast aerial extent of the (sub)volcanic activity during the
Siberian Traps main pulse may explain the severe environmental consequences.