Size-driven preservational and macroecological biases in the latest Maastrichtian terrestrial vertebrate assemblages of North America

Paleobiology, Год журнала: 2021, Номер 48(2), С. 210 - 238

Опубликована: Ноя. 2, 2021

Abstract The end-Cretaceous (K/Pg) mass extinction event is the most recent and well-understood of “big five” triggered establishment modern terrestrial ecosystem structure. Despite depth research into this event, our knowledge upper Maastrichtian deposits globally relies primarily on assemblage-level data limited to a few well-sampled formations in North America, Hell Creek Lance Formations. These assemblages disproportionally affect interpretations important interval. Multiple investigations have quantified diversity patterns within these assemblages, but potential effect formation-level size-dependent taphonomic biases their implications dynamics remains unexplored. Here, relationship between taphonomy body size Formation dinosaurs mammals are quantitatively analyzed. Small-bodied dinosaur taxa (<70 kg) consistently less complete, unlikely be articulated, delayed description relative large-bodied counterparts. Family-level abundance (particularly skeletons) strongly tied mass, juveniles similarly underrepresented. Mammals show similar nonsignificant trends. results remarkably those from Campanian-aged Dinosaur Park Formation, suggesting widespread strong bias against preservation small taxa, which will result seemingly depauperate assemblage. This taphonomically skewed view small-bodied amid best late samples has significant for understanding speciation (e.g., selectivity) across K/Pg boundary.

Язык: Английский

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Estimation of maximum body size in fossil species: A case study using Tyrannosaurus rex

Ecology and Evolution, Год журнала: 2024, Номер 14(7)

Опубликована: Июль 1, 2024

Among extant species, the ability to sample extremes of body size-one most useful predictors an individual's ecology-is highly unlikely. This improbability is further exaggerated when sampling already incomplete fossil record. We quantify likelihood uppermost limits size in record using

Язык: Английский

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Prey size and ecological separation in spinosaurid theropods based on heterodonty and rostrum shape

The Anatomical Record, Год журнала: 2024, Номер unknown

Опубликована: Авг. 28, 2024

Members of the dinosaur clade Spinosauridae had numerous traits attributed to feeding in or around water, and their apparatus has often been considered analogous modern crocodylians. Here we quantify craniodental morphology compare it Crocodylia. We measured from spinosaurid crocodylian skeletal material area alveoli as a proxy for tooth size determine size-heterodonty. Geometric morphometrics were also conducted on crowns bearing regions skull. Spinosaurids overall relatively large alveoli, both they, crocodylians, isolated enlarged alveoli. Spinosaurines along caudal dentary that baryonychines lacked, which instead additional positions. Size-heterodonty was positively allometric, spinosaurids overlapped with generalist/macro-generalist crocodylians similar sizes. Spinosaurid crown shape morphologies certain slender-longirostrine yet lacked molariform distal typical most rostra mandibles deep undulating margins correlating local sizes, may indicate developmental constraint. particularly long concavity rosette anterior cranial teeth, corresponding bulbous rostral dentary. The well suited quickly striking creating punctures, but not cutting flesh durophagy. jaws interlocked secure prey move deeper into mouth. probably did little oral processing, spinosaurines could have processed vertebrates. Overall, there is no indication restricted fish small aquatic prey.

Язык: Английский

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A review of the non-avian theropod track record and the implications for the Ontogenetic Niche Shift model

Earth-Science Reviews, Год журнала: 2021, Номер 220, С. 103715 - 103715

Опубликована: Июнь 10, 2021

Язык: Английский

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Morphometric and biomorphic variability of theropod footprint characters from Imilchil tracksites (Mid-? Late Jurassic, Central High Atlas, Morocco).

Journal of African Earth Sciences, Год журнала: 2023, Номер 207, С. 105048 - 105048

Опубликована: Сен. 2, 2023

This paper presents the study of 14 new sites with theropod footprints in Imilchil. The focuses on ichnotaxonomic and extramorphological characteristics footprints, analysis their trackways, correlation descriptions published tridactil footprints. objective has been to provide a comparative view ichnites relationship between substrate footprint (in interval its formation current state) data. distribution true or real (including stamps deformed footprints), undertracks, subtracks, eroded is introduced, variation morphological characters due preservation processes analyzed. An exposition measurements trackways also made, comparing them data obtained two other large studied known by team (La Rioja Iouaridène). numerical confirm generality some previous little-known observations repetition distributions related metric dinosaur trackways.

Язык: Английский

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The macroecology of Mesozoic dinosaurs

Biology Letters, Год журнала: 2024, Номер 20(11)

Опубликована: Ноя. 1, 2024

Dinosaurs thrived for over 160 million years in Mesozoic ecosystems, displaying diverse ecological and evolutionary adaptations. Their ecology was shaped by large-scale climatic biogeographic changes, calling a ‘deep-time’ macroecological investigation. These factors include temperature fluctuations the break up of Pangaea, influencing species richness, diversity history. Recent improvements dinosaur fossil record have enabled studies their responses to tectonic, geographic shifts. Trends diversity, body size reproductive traits can now be analysed using quantitative approaches like phylogenetic comparative methods, machine learning Bayesian inference. patterns sometimes align with, but also deviate from, first-order rules (e.g. species–area relationship, latitudinal biodiversity gradient, Bergmann’s rule). Accurate reconstructions palaeobiodiversity niche partitioning require ongoing taxonomic revisions detailed anatomical descriptions. Interdisciplinary research combining sedimentology, geochemistry palaeoclimatology helps uncover environmental conditions driving Fieldwork under-sampled regions, particularly at extremes, is crucial understanding spatial heterogeneity ecosystems across planet. Open science initiatives online databases play key role advancing this field, enriching our deep-time processes, offering new insights into macroecology its broader implications.

Язык: Английский

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A new dinosaur track site from the earliest Cretaceous (Berriasian) part of the Tuchengzi Formation, Hebei Province, China: Implications for morphology, ontogeny and paleocommunity structure

Palaeogeography Palaeoclimatology Palaeoecology, Год журнала: 2021, Номер 580, С. 110619 - 110619

Опубликована: Авг. 13, 2021

Язык: Английский

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Ontogenetic dietary shifts in North American hadrosaurids (Dinosauria: Ornithischia)

Cretaceous Research, Год журнала: 2022, Номер 135, С. 105177 - 105177

Опубликована: Фев. 23, 2022

Ontogenetic niche shifts, the phenomenon whereby animals change their resource use with growth, were probably widespread in dinosaurs, but most studies of duck-billed dinosaur ontogeny have so far focused mainly on development cranial ornamentation. Here, we quantify allometry 13 ecomorphological variables skull and examine tooth microwear a sample North American hadrosaurids to better understand ecological functioning growth. Our results indicate that, consistent Jarman-Bell principle relating body size fibre intake feeding selectivity, juvenile relatively more selective than adult counterparts subsisted softer, low-growing browse cropped using lateral rotations neck. Chewing movements jaw did not differ greatly between growth stages. findings invite further investigation ontogenetic hadrosauromorphs broadly, possible role shifts structuring Late Cretaceous herbivore communities.

Язык: Английский

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First application of dental microwear texture analysis to infer theropod feeding ecology

Palaeontology, Год журнала: 2022, Номер 65(6)

Опубликована: Ноя. 1, 2022

Abstract Theropods were the dominating apex predators in most Jurassic and Cretaceous terrestrial ecosystems. Their feeding ecology has always been of great interest, new computational methods have yielded more detailed reconstructions differences theropod behaviour. Many approaches, however, rely on well‐preserved skulls. Dental microwear texture (DMT) analysis is potentially applicable to isolated teeth, here employed for first time investigate dietary theropods. In particular, we test whether tyrannosaurids show DMT associated with hard‐object than compared Allosaurus ; this would be a sign higher levels osteophagy, as often suggested. We find no significant difference complexity roughness enamel surfaces between tyrannosaurids, which conflicts inferences frequent osteophagic behaviour Tyrannosaurus other Orientation wear features reveals pronounced bi‐directional puncture‐and‐pull mode tyrannosaurids. Our results further indicate ontogenetic niche shift theropods crocodylians, based significantly larger height parameters juvenile might scavenging, resulting bone–tooth contact during feeding. Overall, found very similar extant large, broad‐snouted crocodylians shows similarity throughout Cretaceous.

Язык: Английский

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Comparative cranial biomechanics reveal that Late Cretaceous tyrannosaurids exerted relatively greater bite force than in early‐diverging tyrannosauroids

The Anatomical Record, Год журнала: 2023, Номер 307(5), С. 1897 - 1917

Опубликована: Сен. 29, 2023

Abstract Tyrannosaurus has been an exemplar organism in feeding biomechanical analyses. An adult could exert a bone‐splintering bite force, through expanded jaw muscles and robust skull teeth. While function of thoroughly studied, such analyses have yet to expand other tyrannosauroids, especially early‐diverging tyrannosauroids ( Dilong, Proceratosaurus , Yutyrannus ). In our analysis, we broadly assessed the cranial performance at varying body sizes. Our sample size included small Dilong ), medium‐sized Teratophoneus large Tarbosaurus, Daspletosaurus Gorgosaurus ) incorporation tyrannosaurines different ontogenetic stages (small juvenile Raptorex mid‐sized We used muscle force calculations finite element analysis comprehend tyrannosauroids. Scaled subtemporal fenestrae areas calculated forces show that broad‐skulled exhibited higher than similarly sized Gorgosaurus, The proceratosaurid lower stress most tyrannosaurids. This suggests structural adaptations tyrannosaurids maintained adequate safety factors greater but their crania did not notably decrease bone stress. Similarly, experienced similarly‐sized earlier consistent with adductor juveniles, no more predecessors. As tyrannosauroid increased, so too relative manifested even juveniles giant adults.

Язык: Английский

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