scholarly journals Trace fossils on dinosaur bones reveal ecosystem dynamics along the coast of eastern North America during the latest Cretaceous

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4973
Author(s):  
Chase D. Brownstein
Keyword(s):  
North America ◽  
Marine Invertebrates ◽  
Atlantic Coastal Plain ◽  
Ecosystem Dynamics ◽  
Eastern North America ◽  
Marine Deposits ◽  
Terrestrial Vertebrate ◽  
Atlantic Coastal ◽  
Tibia Shaft

Direct evidence of paleoecological processes is often rare when the fossil record is poor, as in the case of the Cretaceous of eastern North America. Here, I describe a femur and partial tibia shaft assignable to theropods from two Late Cretaceous sites in New Jersey. The former, identifiable as the femur of a large ornithomimosaur, bears several scores interpreted as shark feeding traces. The tibia shaft has punctures and flaked bone from the bites of mid-sized crocodyliforms, the first documented occurrence of crocodyliform traces on dinosaur bone from the Maastrichtian of the Atlantic Coastal Plain. The surface of the partial tibia is also littered with indentations interpreted as the traces of invertebrates, revealing a microcosm of biological interaction on the coastal seafloor of the Cretaceous Atlantic Ocean. Massive crocodyliforms, such as Deinosuchus rugosus and the slightly smaller Deltasuchus motherali, maintained the role of terrestrial vertebrate taphonomic process drivers in eastern North America during the Cretaceous. The report of crocodyliform bite marks on the ornithomimosaur tibia shaft in this manuscript reinforces the importance of the role of crocodyliforms in the modification of terrestrial vertebrate remains during the Cretaceous in North America. The preserved invertebrate traces add to the sparse record of the presence of barnacles and other marine invertebrates on dinosaur bone, and the evidence of shark feeding on the ornithomimosaur femur support the “bloat-and-float” model of terrestrial vertebrate fossil deposition in marine deposits from the Cretaceous of eastern North America.

scholarly journals Theropod hindlimbs with feeding and other traces reveal ecosystem dynamics in the Maastrichtian of eastern North America

2018 ◽  
Author(s):  
Chase D Brownstein
Keyword(s):  
New Jersey ◽  
North America ◽  
Atlantic Coastal Plain ◽  
Ecosystem Dynamics ◽  
Eastern North America ◽  
Terrestrial Vertebrate ◽  
Past Life ◽  
Atlantic Coastal ◽  
Tibia Shaft ◽  
Tooth Marks

Direct documentation of the ecology of past life is often rare when the fossil record is comparatively poor, as in the case of the terrestrial fauna of the Maastrichtian of eastern North America. Here, I describe a femur and partial tibia shaft assignable to theropods from the Maastrichtian Big Brook locality of New Jersey. The former, identifiable to a previously undetected morphotype of large ornithomimosaur, bears several scrapes identifiable as the feeding traces of sharks, adding to the collection of terrestrial vertebrate remains bearing such marks from the state. The latter is littered with tooth marks and punctures from possibly multiple crocodyliform individuals, the first documented occurrence of such traces on dinosaur bone from the Maastrichtian of the Atlantic Coastal Plain. Additionally, its surface is dotted with likely traces of invertebrates, revealing a microcosm of biological interaction from the Maastrichtian New Jersey shoreline. Previously, the massive Campanian crocodylian taxon Deinosuchus rugosus and the slightly smaller Cenomanian-age Texas crocodyliform Deltasuchus motherali have been shown as important drivers of terrestrial vertebrate taphonomy in eastern North America. The report of crocodyliform bite marks on the ornithomimosaur metatarsal shaft in this manuscript reveals that crocodylians continued to play role in the taphonomy of large dinosaurs in eastern North America through the end of the Mesozoic. The preserved invertebrate traces add to the sparse record of their traces on dinosaur bone, and the presence of shark scrapes on the femur supports the “bloat-and-float” model of terrestrial vertebrate fossil deposition in eastern North America.

scholarly journals Theropod hindlimbs with feeding and other traces reveal ecosystem dynamics in the Maastrichtian of eastern North America

2018 ◽  
Author(s):  
Chase D Brownstein
Keyword(s):  
New Jersey ◽  
North America ◽  
Atlantic Coastal Plain ◽  
Ecosystem Dynamics ◽  
Eastern North America ◽  
Terrestrial Vertebrate ◽  
Past Life ◽  
Atlantic Coastal ◽  
Tibia Shaft ◽  
Tooth Marks

Direct documentation of the ecology of past life is often rare when the fossil record is comparatively poor, as in the case of the terrestrial fauna of the Maastrichtian of eastern North America. Here, I describe a femur and partial tibia shaft assignable to theropods from the Maastrichtian Big Brook locality of New Jersey. The former, identifiable to a previously undetected morphotype of large ornithomimosaur, bears several scrapes identifiable as the feeding traces of sharks, adding to the collection of terrestrial vertebrate remains bearing such marks from the state. The latter is littered with tooth marks and punctures from possibly multiple crocodyliform individuals, the first documented occurrence of such traces on dinosaur bone from the Maastrichtian of the Atlantic Coastal Plain. Additionally, its surface is dotted with likely traces of invertebrates, revealing a microcosm of biological interaction from the Maastrichtian New Jersey shoreline. Previously, the massive Campanian crocodylian taxon Deinosuchus rugosus and the slightly smaller Cenomanian-age Texas crocodyliform Deltasuchus motherali have been shown as important drivers of terrestrial vertebrate taphonomy in eastern North America. The report of crocodyliform bite marks on the ornithomimosaur metatarsal shaft in this manuscript reveals that crocodylians continued to play role in the taphonomy of large dinosaurs in eastern North America through the end of the Mesozoic. The preserved invertebrate traces add to the sparse record of their traces on dinosaur bone, and the presence of shark scrapes on the femur supports the “bloat-and-float” model of terrestrial vertebrate fossil deposition in eastern North America.

scholarly journals Statistical Analysis of Paradigmatic Class Richness Supports Greater Paleoindian Projectile-Point Diversity in the Southeast

2016 ◽  
Vol 81 (1) ◽  
pp. 174-192 ◽  
Author(s):  
Metin I. Eren ◽  
Anne Chao ◽  
Chun-Huo Chiu ◽  
Robert K. Colwell ◽  
Briggs Buchanan ◽  
...  
Keyword(s):  
North America ◽  
Atlantic Coastal Plain ◽  
Eastern North America ◽  
Projectile Point ◽  
Tennessee River ◽  
The 1960S ◽  
River Valleys ◽  
First Time ◽  
Atlantic Coastal ◽  
Point Class

AbstractRonald Mason’s hypothesis from the 1960s that the southeastern United States possesses greater Paleoindian projectile-point diversity than other regions is regularly cited, and often assumed to be true, but in fact has never been quantitatively tested. Even if valid, however, the evolutionary meaning of this diversity is contested. Point diversity is often linked to Clovis “origins,” but point diversity could also arise from group fissioning and drift, admixture, adaptation, or multiple founding events, among other possibilities. Before archaeologists can even begin to discuss these scenarios, it is paramount to ensure that what we think we know is representative of reality. To this end, we tested Mason’s hypothesis for the first time, using a sample of 1,056 Paleoindian points from eastern North America arui employing paradigmatic classification and rigorous statistical tools used in the quantification of ecological biodiversity. Our first set of analyses, which compared the Southeast to the Northeast, showed that the Southeast did indeed possess significantly greater point-class richness. Although this result was consistent with Mason’s hypothesis, our second set of analyses, which compared the Upper Southeast to the Lower Southeast and the Northeast showed that in terms of point-class richness the Upper Southeast > Lower Southeast > Northeast. Given current chronometrie evidence, we suggest that this latter result is consistent with the suggestion that the area of the Ohio, Cumberland, and Tennessee River valleys, as well as the mid-Atlantic coastal plain, were possible initial and secondary “staging areas” for colonizing Paleoindian foragers moving from western to eastern North America.

Carabodes of the eastern United States and adjacent Canada (Acari: Oribatida: Carabodidae)

1992 ◽  
Vol 70 (10) ◽  
pp. 2042-2058 ◽  
Author(s):  
R. Marcel Reeves
Keyword(s):  
United States ◽  
North America ◽  
Coastal Plain ◽  
Forest Floor ◽  
Appalachian Mountains ◽  
Atlantic Coastal Plain ◽  
Eastern North America ◽  
Eastern United States ◽  
Thelytokous Parthenogenesis ◽  
Atlantic Coastal

Adults of four new species of Carabodes, C. chandleri, C. erectus, C. interruptus, and C. pentasetosus, and the immatures of C. erectus, are described. All have been collected from a variety of forest-floor habitats, with C. chandleri, C. interruptus, and C. pentasetosus more common in leaf litter, and C. erectus preferring polyporous fungi. All four species are widely distributed in eastern North America, with C. chandleri, C. erectus, and C. interruptus more abundant in samples from the Appalachian Mountains and C. pentasetosus in those from the Atlantic coastal plain. Thelytokous parthenogenesis is suspected to occur in C. pentasetosus n.sp. and Carabodes granulatus Banks. A key to the 19 species of Carabodes found in North America is provided.

Regional attenuation models in Central and Eastern North America using the NGA-East database

2021 ◽  
pp. 875529302110187
Author(s):  
Jeff Bayless
Keyword(s):  
North America ◽  
Frequency Dependence ◽  
Gulf Coast ◽  
Site Response ◽  
Epistemic Uncertainty ◽  
Amplitude Spectrum ◽  
Active Regions ◽  
Atlantic Coastal Plain ◽  
Eastern North America ◽  
Anelastic Attenuation

The anelastic attenuation term found in ground motion prediction equations (GMPEs) represents the distance dependence of the effect of intrinsic and scattering attenuation on the wavefield as it propagates through the crust and contains the frequency-dependent quality factor, [Formula: see text], which is an inverse measure of the effective anelastic attenuation. In this work, regional estimates of [Formula: see text] in Central and Eastern North America (CENA) are developed using the NGA-East regionalization. The technique employed uses smoothed Fourier amplitude spectrum (FAS) data from well-recorded events in CENA as collected and processed by NGA-East. Regional [Formula: see text] is estimated using an assumption of average geometrical spreading applicable to the distance ranges considered. Corrections for the radiation pattern effect and for site response based on [Formula: see text] result in a small but statistically significant improvement to the residual analysis. Apparent [Formula: see text] estimates from multiple events are combined within each region to develop the regional models. Models are provided for three NGA-East regions: the Gulf Coast, Central North America, and the Appalachian Province. Consideration of the model uncertainties suggests that the latter two regions could be combined. There were not sufficient data to adequately constrain the model in the Atlantic Coastal Plain region. Tectonically stable regions are usually described by higher [Formula: see text] and weaker frequency dependence ([Formula: see text]), while active regions are typically characterized by lower [Formula: see text] and stronger frequency dependence, and the results are consistent with these expectations. Significantly different regional [Formula: see text] is found for events with data recorded in multiple regions, which supports the NGA-East regionalization. An inspection of two well-recorded events with data both in the Mississippi embayment and in southern Texas indicates that the Gulf Coast regionalization by Cramer in 2017 may be an improvement to that of NGA-East for anelastic attenuation. The [Formula: see text] models developed serve as epistemic uncertainty alternatives in CENA based on a literature review and a comparison with previously published models.

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