Exploring the effects of weighting against homoplasy in genealogies of palaeontological phylogenetic matrices

Cladistics, Journal Year: 2024, Volume and Issue: 40(3), P. 242 - 281

Published: May 10, 2024

Abstract Although simulations have shown that implied weighting (IW) outperforms equal (EW) in phylogenetic parsimony analyses, against homoplasy lacks extensive usage palaeontology. Iterative modifications of several matrices the last decades resulted genealogies datasets allow evaluation differences stability results for alternative character methods directly on empirical data. Each generation was compared most recent each genealogy because it is assumed comprehensive (higher sampling), revised (fewer misscorings) and complete (lower amount missing data) matrix genealogy. The analyses were conducted six different under EW IW extended (EIW) with a range concavity constant values ( k ) between 3 30. Pairwise comparisons trees using Robinson–Foulds distances normalized by total number groups, distortion coefficient, subtree pruning regrafting moves, proportional sum group dissimilarities. consistently show EIW produce more similar to those dataset than vast majority all comparative measures. This significant almost these originally analysed only EW. Implied do not outperform other unambiguously. Euclidean based principal components analysis measures ranges k‐ retrieve genealogies. There positive linear correlation optimal terminals generations. could be employed inform about used size but caveat this emergent relationship still relies low sample

Language: Английский

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A new early‐diverging probainognathian cynodont and a revision of the occurrence of cf. Aleodon from the Chañares Formation, northwestern Argentina: New clues on the faunistic composition of the latest Middle–?earliest Late Triassic Tarjadia Assemblage Zone

The Anatomical Record, Journal Year: 2024, Volume and Issue: 307(4), P. 818 - 850

Published: Jan. 29, 2024

Abstract The Chañares Formation (Ischigualasto‐Villa Unión Basin) is worldwide known by its exquisitely preserved fossil record of latest Middle‐to‐early Late Triassic tetrapods, including erpetosuchids, “rauisuchians,” proterochampsids, gracilisuchids, dinosauromorphs, pterosauromorphs, kannemeyeriiform dicynodonts, and traversodontid, chiniquodontid probainognathid cynodonts, coming from the Tarjadia (bottom) Massetognathus ‐ Chanaresuchus (top) Assemblage Zones lower member. Regarding most profuse knowledge comes traditional layers discovered Alfred Romer his team in 1960s that are now enclosed Zone (AZ). In this contribution we focus our study on probainognathian cynodonts levels Zone. We describe a new cynodont with transversely broad postcanine teeth ( Riojanodon nenoi gen. et sp. nov.) which related to genus Aleodon . addition, specimen CRILAR‐Pv 567 previously referred cf. here described, compared, included phylogenetic analysis. It considered as an indeterminate Aleodontinae nov., clade proposed chiniquodontids upper postcanines, having cuspidated sectorial labial margin lingual platform twice broader than cingulum. Cromptodon mamiferoides , Cerro de Las Cabras (Cuyo Basin), was also analysis recovered Aleodontinae. indet. reinforce faunal differentiation between Zones, member Formation, inform diverse both teeth.

Language: Английский

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A comprehensive phylogenetic analysis on early ornithischian evolution

Journal of Systematic Palaeontology, Journal Year: 2024, Volume and Issue: 22(1)

Published: June 21, 2024

Resolving the evolutionary relationships of early diverging ('basal') ornithischian dinosaurs is a challenging topic in palaeontology, with multiple competing hypotheses on phylogenetic heterodontosaurids, 'hypsilophodontids', and other early-diverging forms. These cannot be directly compared because they are derived from differently constructed datasets (i.e. distinct samples taxa characters). This study aims to address these issues by revising combining into single analysis order create most comprehensive dataset for investigation ornithischians. A diphyletic model Dinosauria supported, silesaurs nesting as members Ornithischia. Heterodontosauridae resolved clade non-genasaurian ornithischians, rejecting potential relationship Marginocephalia. 'Hypsilophodontid' span neornithischian ornithopod stem, Thescelosauridae sister taxon Cerapoda. more restricted Ornithopoda composed five main clades: Hypsilophodontidae, Rhabdodontomorpha, Elasmaria, Dryosauridae Ankylopollexia. Hypsilophodontidae valid clade, reduced two European Barremian taxa. Rhabdodontomorpha does not contain Muttaburrasaurus originally proposed, but instead expands include North American formed Convolosaurus, Iani Tenontosaurus. Elasmaria contains all non-dryomorph Gondwanan ornithopods, its possessing body plans. New results comparison previous studies suggest that some 'true dryosaurids' various euiguanodontians may closely related either or Results group 'hypsilophodontids' larger clades, significantly reducing number extension ghost lineages throughout Neornithischia. clades also show degree endemism, different present at continents Late Cretaceous. new unifying works will provide framework future origins relations attempting find stability among hypotheses.

Language: Английский

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Micro-CT reconstruction reveals new information about the phylogenetic position and locomotion of the Early Cretaceous bird Iberomesornis romerali

Geobios, Journal Year: 2025, Volume and Issue: unknown

Published: March 1, 2025

Language: Английский

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Taxonomic, palaeobiological and evolutionary implications of a phylogenetic hypothesis for Ornithischia (Archosauria: Dinosauria)

Zoological Journal of the Linnean Society, Journal Year: 2022, Volume and Issue: 196(4), P. 1273 - 1309

Published: Aug. 24, 2022

Abstract The origin and evolutionary relationships of ornithischian dinosaurs are topics that have undergone a series substantial revisions. At present there several competing hypotheses concerning the relationship between Ornithischia other principal clades Dinosauria. Some posited tree topology within Dinosauria imply ‘ghost-lineage’ for (whose representatives make their first unambiguous appearance in Hettangian) extends through portion Triassic time. In contrast, placed conventionally dinosauromorph (stem-lineage Dinosauria) taxa clade Ornithischia. Recently, large-scale phylogenetic analysis recovered an array taxa, known as ‘silesaurids’, paraphyletic assemblage (referred to this article using informal terms silesaurs or silesaurians) on branch leading This latter hypothesis would account apparent absence ornithischians, because stem-lineage ornithischians (silesaurs article) exclusively Triassic. However, produced novel used dataset that, its original form, did not include all early (sensu lato), incorporate anatomical characters been suggested unite with dinosaurian (Theropoda Sauropodomorpha). Nor initial study go expand upon some important taxonomic, palaeobiological implications links addresses these issues by expansion re-analysis dataset. results find further support comprise grouping stem successive silesaur acquire anagenetically process culminates assembly what may be described ‘traditional’ ornithischian. overall consensus remains but little changed from analysis, despite addition new characters. To provide stability area preserve most relevant taxonomic names, we suggest revised framework is consistent topology. We retain name total-group (traditional stem-lineage), while resuscitate originally proposed Richard Owen, Prionodontia (= ‘coarse edged teeth’) containing only so-called traditional ‘bird-hipped’) dinosaurs. also erect Parapredentata more exclusive subclade intended clarity degree analyses data continue refine re-shape tree. presented represent stage our attempt establish dinosaur which character definitions scores agreed consistently.

Language: Английский

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Osteohistological insight into the growth dynamics of early dinosaurs and their contemporaries

PLoS ONE, Journal Year: 2024, Volume and Issue: 19(4), P. e0298242 - e0298242

Published: April 3, 2024

Dinosauria debuted on Earth’s stage in the aftermath of Permo-Triassic Mass Extinction Event, and survived two other Triassic extinction intervals to eventually dominate terrestrial ecosystems. More than 231 million years ago, Upper Ischigualasto Formation west-central Argentina, dinosaurs were just getting warmed up. At this time, represented a minor fraction ecosystem diversity. Members tetrapod clades, including synapsids pseudosuchians, shared convergently evolved features related locomotion, feeding, respiration, metabolism could have risen later dominance. However, it was that radiated Mesozoic most significantly terms body size, diversity, global distribution. Elevated growth rates are one adaptations set apart, particularly from their contemporary crocodilian mammalian compatriots. When did elevated first evolve? How strategies earliest known compare with those tetrapods ecosystems? We studied femoral bone histology an array early alongside non-dinosaurian contemporaries order test whether oldest exhibited novel strategies. Our results indicate vertebrate fauna collectively exhibits relatively high rates. Dinosaurs among fastest growing taxa sample, but they occupied niche crocodylomorphs, archosauriformes, large-bodied pseudosuchians. Interestingly, these grew at least as quickly, more continuously sauropodomorph theropod Mesozoic. These data suggest that, while ancestral for likely played significant role dinosaurs’ ascent within ecosystems, not them apart contemporaries.

Language: Английский

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A new silesaurid from Carnian beds of Brazil fills a gap in the radiation of avian line archosaurs

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: April 11, 2023

Comprising the oldest unequivocal dinosauromorphs in fossil record, silesaurs play an important role Triassic radiation of dinosaurs. These reptiles provide main source information regarding ancestral body plan dinosaurs, as well basis for biogeographic models. Nevertheless, co-occurrence and dinosaurs is rare, which hampers reliable ecological inferences. Here we present first species silesaur from dinosaur-bearing beds Brazil. Amanasaurus nesbitti gen. et sp. nov. possesses a unique set femoral traits among silesaurs, including occurrence anterior trochanter separated by shaft marked cleft. Its length indicates that new rivals size with most coeval This find challenges assumption faunas where unambiguous co-occurred, were relatively smaller. Moreover, presence dinosaur-sized within ecosystems lagerpetids, sauropodomorphs herrerasaurids reinforces complex scenario early Pan-Aves. Silesaurs-independent their phylogenetic position-persisted during Period, its plesiomorphic advancing through dawn instead lineages decrease time.

Language: Английский

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A complete skull of a stem mammal from the Late Triassic of Brazil illuminates the early evolution of prozostrodontian cynodonts

Journal of Mammalian Evolution, Journal Year: 2023, Volume and Issue: 30(2), P. 299 - 317

Published: Jan. 30, 2023

Language: Английский

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Uncovering hidden footprints: revision of the Lower Jurassic (Sinemurian) Razorback Beds – home to Australia’s earliest reported dinosaur trackway

Historical Biology, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 8

Published: Feb. 21, 2024

This investigation uses archival data (circa 1954) to elucidate new details on Australia's first scientifically described dinosaur trackway, located at the Fireclay Caverns-Site A, Mount Morgan, Queensland. A high-resolution photograph reveals two additional prints, extending known sequence from four six tracks. Leveraging this extended dataset, we have quantified temporospatial variations assess trackmaker's locomotion. Our findings reveal a decrease in stride and step lengths towards end of accompanied by slight directional shift east-southeast east reduction walking speed maximum 3.8–1.8 km/hr. The life reconstruction animation trackmaker supports gait calculated relative demonstrates biomechanically plausible limb movements. By incorporating non-traditional methods, such as temporal trackway analysis its translation animation, establish broader framework for conventional ichnological studies. approach enhances our interpretation dynamic record encapsulated fossil trackways, enabling us visualise scrutinise behaviour extinct trackmakers.

Language: Английский

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Stranger in the nest: On the biostratigraphic relevance of a new record of a traversodontid cynodont in southern Brazil (Candelária Sequence, Upper Triassic)

Palaeoworld, Journal Year: 2024, Volume and Issue: unknown

Published: July 1, 2024

Language: Английский

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