Mechanistic phylodynamic models do not provide conclusive evidence that non-avian dinosaurs were in decline before their final extinction

Cambridge Prisms Extinction, Journal Year: 2024, Volume and Issue: 2

Published: Jan. 1, 2024

Abstract Phylodynamic models can be used to estimate diversification trajectories from time-calibrated phylogenies. Here we apply two such phylogenies of non-avian dinosaurs, a clade whose evolutionary history has been widely debated. Although some authors have suggested that the experienced decline in diversity, potentially starting millions years before end-Cretaceous mass extinction, others group remained highly diverse right up until Cretaceous-Paleogene (K-Pg) boundary. Our results show model assumptions, likely with respect incomplete sampling, large impact on whether dinosaurs appear long-term or not. The are also sensitive topology and branch lengths phylogeny used. Developing comprehensive sampling bias, building larger more accurate phylogenies, necessary steps for us determine dinosaur diversity was not extinction.

Language: Английский

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The complete mitogenome of Amazonian Brachyplatystoma filamentosum and the evolutionary history of body size in the order Siluriformes

Scientific Reports, Journal Year: 2025, Volume and Issue: 15(1)

Published: March 21, 2025

The order Siluriformes (catfish) is one of the largest groups fish. Diversity in body size among its species, which range from a few centimeters to 4 meters, makes an interesting group investigate evolution. Here, we present complete mitogenome Brachyplatystoma filamentosum (Piraíba), Amazonian catfish, explore evolutionary history and their dynamics. Piraíba's mtDNA 16,566 bp long, with GC content 42.21% D-loop 911 bp. Phylogenetic analysis was conducted using protein-coding sequences, tRNAs, rRNAs Piraíba 137 other species. Time-calibrated maximum likelihood trees estimated origin be ~118.4 Ma, Loricarioidei suborder diversifying first, followed by Diplomystoidei Siluroidei. Siluroidei experienced rapid expansion around 94.1 Ma. Evolutionary dynamics revealed 16 positive 11 negative directional changes Siluriformes, no global trend toward larger or smaller sizes, showing significant increase (5.65 times over 40.8 Ma). We discuss how biological, ecological environmental factors could have shaped evolution this group.

Language: Английский

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Paleohistology of Cretaceous‐Paleogene pan‐trionychian turtle shells

Journal of Anatomy, Journal Year: 2025, Volume and Issue: unknown

Published: May 7, 2025

Abstract At the end of Cretaceous, a bolide impact wiped out ~75% life on Earth, but turtles show minimal gross anatomical changes. Herein, we examine shell histology from trionychid 2 million years before and 8 after extinction event. We collected over 25,000 semi‐quantitative quantitative measurements statistically compared them against latitude, stratigraphic position, lithologic context, ontogeny, phylogeny, K/Pg survivorship to better understand various ways in which each respective variable influences histology. find that trionychids mudstones higher section were larger older. Traits hypothesized be biomechanically relevant, like plywood‐like structure suture margins, showed change across boundary, shells northern Danian deposits do appear selected for biomechanical resistivity. Turtles Helopanoplia Gilmoremys had well‐vascularized external cortices with deep ornamentation pits devoid Sharpey's fibers, likely enclosed dense vascular capillary bed. These also have more intact primary cortical tissues smaller medullary regions, meaning they remodeled their infrequently other turtles. Because is used as calcium storage reservoir combat metabolic respiratory blood acidosis, suggest bed nestled among may aided cutaneous respiration, turn lessened reliance remodeling. are few go extinct at suggesting this adaptation was maladaptive during extinction, though lack chronological resolution required infer intermediate selective mechanisms. Paleocene taxa generally subtle uniform fiber distribution abundant Specimens ~9500 only modestly later Paleogene specimens, freshwater ecosystems almost fully recovered by interval.

Language: Английский

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On the role of tectonics in stimulating the Cretaceous diversification of mammals

Earth-Science Reviews, Journal Year: 2023, Volume and Issue: 248, P. 104630 - 104630

Published: Nov. 26, 2023

Language: Английский

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Colonization of the ocean floor by jawless vertebrates across three mass extinctions

BMC Ecology and Evolution, Journal Year: 2024, Volume and Issue: 24(1)

Published: June 13, 2024

Abstract Background The deep (> 200 m) ocean floor is often considered to be a refugium of biodiversity; many benthic marine animals appear share ancient common ancestry with nearshore and terrestrial relatives. Whether this pattern holds for vertebrates obscured by poor understanding the evolutionary history oldest vertebrate clades. Hagfishes are jawless that either living sister all or form clade lampreys, only other surviving fishes. Results We use hagfish fossil record molecular data recognized genera construct novel hypothesis relationships diversification. find crown hagfishes persisted through three mass extinctions after appearing in Permian ~ 275 Ma, making them one lineages. In contrast most vertebrates, we consistently infer origin continental slope occupation dates Paleozoic. Conclusion Our results establish as members demersal faunas suggest prolonged accumulation sea biodiversity.

Language: Английский

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Relict duck-billed dinosaurs survived into the last age of the dinosaurs in subantarctic Chile

Science Advances, Journal Year: 2023, Volume and Issue: 9(24)

Published: June 16, 2023

In the dusk of Mesozoic, advanced duck-billed dinosaurs (Hadrosauridae) were so successful that they likely outcompeted other herbivores, contributing to declines in dinosaur diversity. From Laurasia, hadrosaurids dispersed widely, colonizing Africa, South America, and, allegedly, Antarctica. Here, we present first species a from subantarctic region, Gonkoken nanoi, early Maastrichtian age Magallanes, Chile. Unlike duckbills further north Patagonia, descends North American forms diverging shortly before origin Hadrosauridae. However, at time, non-hadrosaurids America had become replaced by hadrosaurids. We propose ancestors arrived earlier and reached south, into regions where never arrived: All alleged Antarctic remains could belong non-hadrosaurid like Gonkoken. Dinosaur faunas world underwent qualitatively different changes Cretaceous-Paleogene asteroid impact, which should be considered when discussing their possible vulnerability.

Language: Английский

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Deep learning resilience inference for complex networked systems

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Oct. 24, 2024

Resilience, the ability to maintain fundamental functionality amidst failures and errors, is crucial for complex networked systems. Most analytical approaches rely on predefined equations node activity dynamics simplifying assumptions network topology, limiting their applicability real-world Here, we propose ResInf, a deep learning framework integrating transformers graph neural networks infer resilience directly from observational data. ResInf learns representations of topology without assumptions, enabling accurate inference low-dimensional visualization. Experimental results show that significantly outperforms methods, with an F1-score improvement up 41.59% over Gao-Barzel-Barabási 14.32% spectral dimension reduction. It also generalizes unseen topologies maintains robust performance despite disturbances. Our findings suggest addresses important gap in systems, offering fresh perspective incorporating data-driven modeling. Estimation resilience, when occur, usually requires prior knowledge dynamics. The authors model predict based data activities topology.

Language: Английский

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The macroecology of Mesozoic dinosaurs

Biology Letters, Journal Year: 2024, Volume and Issue: 20(11)

Published: Nov. 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.

Language: Английский

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The dinosaur boom in the Cretaceous

Geological Society London Special Publications, Journal Year: 2023, Volume and Issue: 544(1)

Published: Oct. 25, 2023

Abstract Dinosaurs were thriving at the beginning of Cretaceous, and yet major changes had occurred across Jurassic–Cretaceous boundary. The sauropods replaced by ornithopods as dominant herbivores, which has been explained many ecological scenarios, including replacement gymnosperms angiosperms land plants. ornithischians went on to radiate substantially in mid Late with key clades (hadrosaurs, ceratopsians, ankylosaurs) specializing different feeding modes diets, reaching huge abundance faunas. New computational methods allow palaeobiologists assess aspects palaeobiology, macroecology macroevolution dinosaurs through Cretaceous testable repeatable ways. These new approaches have shed light mysteries, such whether ate flowers, why hadrosaurs so successful some theropods became larger or smaller, switched from carnivory herbivory. There are further debates around final demise dinosaurs, where regional global data suggest group was decline latter part before they finished asteroid impact.

Language: Английский

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Genomes of the Orestias pupfish from the Andean Altiplano shed light on their evolutionary history and phylogenetic relationships within Cyprinodontiformes

BMC Genomics, Journal Year: 2024, Volume and Issue: 25(1)

Published: June 18, 2024

Abstract Background To unravel the evolutionary history of a complex group, comprehensive reconstruction its phylogenetic relationships is crucial. This requires meticulous taxon sampling and careful consideration multiple characters to ensure complete accurate reconstruction. The position Orestias genus has been estimated partly on unavailable or incomplete information. As consequence, it was assigned family Cyprindontidae, relating this Andean fish other geographically distant genera distributed in Mediterranean, Middle East North Central America. In study, using genome sequencing, we aim clarify within Cyprinodontiformes order. Results We sequenced three species from Altiplano. Our analysis revealed that small size (~ 0.7 Gb) caused by contraction transposable element (TE) content, particularly DNA elements short interspersed nuclear (SINEs). Using predicted gene sequences, generated tree 902 orthologs extracted all 32 available genomes as well outgroup species. complemented with time calibration considering 12 molecular markers (eight four mitochondrial genes) stratified consider 198 nearly families Overall, our results show closeness directly related geographical distance. Importantly, found not part Cyprinodontidae family, more closely South American fauna, being Fluviphylacidae closest sister group. Conclusions linked ichthyofauna should no longer be considered member family. Instead, submit belongs Orestiidae suggested Freyhof et al. (2017), group Amazonian Orinoco basins. These two groups likely diverged during Late Eocene concomitant hydrogeological changes landscape.

Language: Английский

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