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1.
Commun Biol ; 5(1): 1023, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175597

RESUMO

Fossil material in amber from Myanmar can provide important insights into mid-Cretaceous forest ecosystems. However, Myanmar amber has been receiving increased international attention due to reported links between amber mining and the ongoing humanitarian crisis in northern Myanmar, as well as the legal issues associated with its exportation. Here, we conduct a bibliometric analysis of Myanmar amber publications (1990-2021) and demonstrate how research interest in Myanmar amber is explicitly linked to major political, legal, and economic changes. An analysis of the authorship networks for publications on amber inclusions reveals how current research practices have excluded Myanmar researchers from the field. In addition, the international trade of Myanmar amber with fossil inclusions falls into a legal 'grey-zone' which continues to be exploited. This case study vividly demonstrates that systemic changes, alongside an increased awareness of inequitable research practices amongst the broader scientific and allied communities, are urgently needed to curb illegal practices in palaeontology.


Assuntos
Âmbar , Paleontologia , Comércio , Ecossistema , Internacionalidade , Política
2.
Curr Biol ; 32(18): R964-R967, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-36167048

RESUMO

Developmental biology and paleontology have a long history of reciprocal illumination. New research reveals that the embryonic development of the bird pelvis parallels the evolutionary transition from archosaurs to birds.


Assuntos
Dinossauros , Animais , Evolução Biológica , Biologia do Desenvolvimento , Dinossauros/anatomia & histologia , Fósseis , Paleontologia , Codorniz
3.
Sci Rep ; 12(1): 16407, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36180510

RESUMO

Dual-energy computed tomography (DECT) is an imaging technique that combines nondestructive morphological cross-sectional imaging of objects and the quantification of their chemical composition. However, its potential to assist investigations in paleontology has not yet been explored. This study investigates quantitative DECT for the nondestructive density- and element-based material decomposition of fossilized bones. Specifically, DECT was developed and validated for imaging-based calcium and fluorine quantification in bones of five fossil vertebrates from different geological time periods and of one extant vertebrate. The analysis shows that DECT material maps can differentiate bone from surrounding sediment and reveals fluorine as an imaging marker for fossilized bone and a reliable indicator of the age of terrestrial fossils. Moreover, the jaw bone mass of Tyrannosaurus rex showed areas of particularly high fluorine concentrations on DECT, while conventional CT imaging features supported the diagnosis of chronic osteomyelitis. These findings highlight the relevance of radiological imaging techniques in the natural sciences by introducing quantitative DECT imaging as a nondestructive approach for material decomposition in fossilized objects, thereby potentially adding to the toolbox of paleontological studies.


Assuntos
Paleontologia , Tomografia Computadorizada por Raios X , Animais , Cálcio , Flúor , Tomografia Computadorizada por Raios X/métodos , Vertebrados
4.
J Hum Evol ; 170: 103237, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35988385

RESUMO

The Abocador de Can Mata (ACM) composite stratigraphic sequence (els Hostalets de Pierola, Vallès-Penedès Basin, NE Iberian Peninsula) has yielded a diverse primate assemblage from the late Aragonian (Middle to Late Miocene). Detailed litho-, bio-, and magnetostratigraphic control has enabled an accurate dating of these fossil remains. Comparable data, however, were lacking for the nearby locality of Can Mata 1 (CM1), which yielded a dryopithecine canine of a female individual. Given the lack of hipparionin equids and giraffids, CM1 has been correlated to the latest Aragonian (Mammal Neogene [MN] zone MN7+8). Here we revise the age of CM1 based on fieldwork and associated paleomagnetic samplings undertaken in 2018-2021. Our results extend the ACM composite sequence upward and indicate that CM1 correlates to the earliest Vallesian (MN9). The updated ACM sequence has a thickness of ∼300 m and comprises 12 magnetozones correlated to subchrons C5Ar.1r to C5n.2n (∼12.6-11.1 Ma; latest MN6 to earliest MN9, late Aragonian to earliest Vallesian). CM1 is correlated to C5r.1r (11.146-11.056 Ma), with an interpolated age of 11.11 Ma, thus postdating the dispersal of hipparionin horses into the Vallès-Penedès Basin-which is correlated to the previous subchron C5r.1n, with an interpolated age of 11.18 Ma, and by definition marks the beginning of the Vallesian. CM1 also minimally postdates the earliest record of giraffids at ACM-representing their earliest well-dated occurrence in the basin-being correlated to C5r.1n with an interpolated age of 11.11 Ma. We conclude that CM1 has an earliest Vallesian (MN9) age of ∼11.1 Ma, intermediate between the Aragonian dryopithecins and the Vallesian hispanopithecins. Ongoing paleontological surveillance at ACM thus offers the prospect to yield additional earliest Vallesian ape remains, which are essential to clarify their taxonomic allocation as well as to confirm whether hispanopithecins evolved locally from dryopithecins rather than immigrating from elsewhere during MN9.


Assuntos
Hominidae , Animais , Cães , Feminino , Fósseis , Cavalos , Mamíferos , Paleontologia , Primatas , Répteis
5.
Anat Rec (Hoboken) ; 305(10): 2343-2352, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35912969

RESUMO

Crocodilians inspire researchers and the public alike with their explosive hunting methodologies, distinct craniofacial and dental morphology, and resplendent fossil record. This special issue highlights recent advances in the biology and paleontology of this fascinating lineage of vertebrates. The authors in this volume bring crocodylians and their extinct ancestors to life using a variety of approaches including fieldwork, imaging, 3D modeling, developmental biology, physiological monitoring, dissection, and a host of other comparative methods. Our journey begins with early crocodylomorphs from the Triassic, carries us through the radiation of crocodyliforms during the rest of the Mesozoic Era, and finally celebrates the diversification development and biology of extant crocodylians. Crocodyliform science has grown appreciably the past few decades. New fossil species and genetic evidence continue to keep phylogenies and our understanding of relationships wavering in key places of the tree such as the relationships of the extinct marine thalattosuchians as well as still living species like gharials. The application of imaging approaches and 3D modeling to both preserved tissues as well as living specimens is now revealing patterns in brain and lung evolution and function, growth strategies, and feeding and locomotor behaviors across the lineage. Comparative anatomical studies are offering new data on genitals, cephalic venous drainage and thoracoabdominal pressures. The new discoveries found here only reveal there is far more work to be done to understand the biology and behavior responsible for the great radiation extinct suchians and their crocodylian descendants experienced during their conquest of Mesozoic and Tertiary ecosystems.


Assuntos
Jacarés e Crocodilos , Jacarés e Crocodilos/anatomia & histologia , Animais , Evolução Biológica , Ecossistema , Fósseis , Paleontologia , Filogenia
6.
Nature ; 609(7927): 541-546, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35978194

RESUMO

The early history of deuterostomes, the group composed of the chordates, echinoderms and hemichordates1, is still controversial, not least because of a paucity of stem representatives of these clades2-5. The early Cambrian microscopic animal Saccorhytus coronarius was interpreted as an early deuterostome on the basis of purported pharyngeal openings, providing evidence for a meiofaunal ancestry6 and an explanation for the temporal mismatch between palaeontological and molecular clock timescales of animal evolution6-8. Here we report new material of S. coronarius, which is reconstructed as a millimetric and ellipsoidal meiobenthic animal with spinose armour and a terminal mouth but no anus. Purported pharyngeal openings in support of the deuterostome hypothesis6 are shown to be taphonomic artefacts. Phylogenetic analyses indicate that S. coronarius belongs to total-group Ecdysozoa, expanding the morphological disparity and ecological diversity of early Cambrian ecdysozoans.


Assuntos
Cordados , Filogenia , Animais , Cordados/anatomia & histologia , Fósseis , Boca , Paleontologia
7.
Sci Rep ; 12(1): 13530, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35941267

RESUMO

During the last century, Grotta Romanelli (Southern Italy) has been a reference site for the European Late Pleistocene stratigraphy, due to its geomorphological setting and archaeological and palaeontological content. The beginning of the sedimentation inside the cave was attributed to the Last Interglacial (MISs 5e) and the oldest unearthed evidence of human occupation, including remains of hearths, was therefore referred to the Middle Palaeolithic. Recent surveys and excavations produced new U/Th dates, palaeoenvironmental interpretation and a litho-, morpho- and chrono-stratigraphical reassessment, placing the oldest human frequentation of the cave between MIS 9 and MIS 7, therefore embracing Glacial and Interglacial cycles. These new data provide evidence that the sea reached the cave during the Middle Pleistocene and human occupation occurred long before MISs 5e and persisted beyond the Pleistocene- Holocene boundary.


Assuntos
Arqueologia , Fósseis , Cavernas , Humanos , Itália , Paleontologia
8.
Elife ; 112022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35818828

RESUMO

The lobe-finned fish, lungfish (Dipnoi, Sarcoptergii), have persisted for ~400 million years from the Devonian Period to present day. The evolution of their dermal skull and dentition is relatively well understood, but this is not the case for the central nervous system. While the brain has poor preservation potential and is not currently known in any fossil lungfish, substantial indirect information about it and associated structures (e.g. labyrinths) can be obtained from the cranial endocast. However, before the recent development of X-ray tomography as a palaeontological tool, these endocasts could not be studied non-destructively, and few detailed studies were undertaken. Here, we describe and illustrate the endocasts of six Palaeozoic lungfish from tomographic scans. We combine these with six previously described digital lungfish endocasts (4 fossil and 2 recent taxa) into a 12-taxon dataset for multivariate morphometric analysis using 17 variables. We find that the olfactory region is more highly plastic than the hindbrain, and undergoes significant elongation in several taxa. Further, while the semicircular canals covary as an integrated module, the utriculus and sacculus vary independently of each other. Functional interpretation suggests that olfaction has remained a dominant sense throughout lungfish evolution, and changes in the labyrinth may potentially reflect a change from nektonic to near-shore environmental niches. Phylogenetic implications show that endocranial form fails to support monophyly of the 'chirodipterids'. Those with elongated crania similarly fail to form a distinct clade, suggesting these two paraphyletic groups have converged towards either head elongation or truncation driven by non-phylogenetic constraints.


Assuntos
Evolução Biológica , Fósseis , Animais , Encéfalo/diagnóstico por imagem , Peixes , Paleontologia , Crânio/anatomia & histologia , Crânio/diagnóstico por imagem
12.
Chem Rev ; 122(16): 13401-13446, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35839101

RESUMO

Paleoproteomics, the study of ancient proteins, is a rapidly growing field at the intersection of molecular biology, paleontology, archaeology, paleoecology, and history. Paleoproteomics research leverages the longevity and diversity of proteins to explore fundamental questions about the past. While its origins predate the characterization of DNA, it was only with the advent of soft ionization mass spectrometry that the study of ancient proteins became truly feasible. Technological gains over the past 20 years have allowed increasing opportunities to better understand preservation, degradation, and recovery of the rich bioarchive of ancient proteins found in the archaeological and paleontological records. Growing from a handful of studies in the 1990s on individual highly abundant ancient proteins, paleoproteomics today is an expanding field with diverse applications ranging from the taxonomic identification of highly fragmented bones and shells and the phylogenetic resolution of extinct species to the exploration of past cuisines from dental calculus and pottery food crusts and the characterization of past diseases. More broadly, these studies have opened new doors in understanding past human-animal interactions, the reconstruction of past environments and environmental changes, the expansion of the hominin fossil record through large scale screening of nondiagnostic bone fragments, and the phylogenetic resolution of the vertebrate fossil record. Even with these advances, much of the ancient proteomic record still remains unexplored. Here we provide an overview of the history of the field, a summary of the major methods and applications currently in use, and a critical evaluation of current challenges. We conclude by looking to the future, for which innovative solutions and emerging technology will play an important role in enabling us to access the still unexplored "dark" proteome, allowing for a fuller understanding of the role ancient proteins can play in the interpretation of the past.


Assuntos
Paleontologia , Proteômica , Animais , Arqueologia , Fósseis , Humanos , Paleontologia/métodos , Filogenia , Proteoma , Proteômica/métodos
14.
Curr Biol ; 32(11): R535-R538, 2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35671731

RESUMO

Ancient DNA provides answers to long-standing debates about past human history. New work using demographic modeling on ancient genomes documents the nature and timing of the demographic processes - population size changes, divergences and admixture - that took place in prehistoric Europe.


Assuntos
Genoma Humano , Genômica , DNA Antigo , Demografia , Europa (Continente) , História Antiga , Humanos , Paleontologia
15.
Sci Rep ; 12(1): 9794, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35697774

RESUMO

Outstanding questions about human evolution include systematic connections between critical landscape resources-such as water and food-and how these shaped the competitive and biodiverse environment(s) that our ancestors inhabited. Here, we report fossil n-alkyl lipid biomarkers and their associated δ13C values across a newly discovered Olduvai Gorge site (AGS) dated to 1.84 million years ago, enabling a multiproxy analysis of the distributions of critical local landscape resources across an explicit locus of hominin activity. Our results reveal that AGS was a seasonally waterlogged, largely unvegetated lakeside site situated near an ephemeral freshwater river surrounded by arid-adapted C4 grasses. The sparse vegetation at AGS contrasts with reconstructed (micro)habitats at the other anthropogenic sites at Olduvai Gorge, suggesting that central-provisioning places depended more heavily on water access than vegetation viz. woody plants as is often observed for modern hunter-gatherers. As hominins at AGS performed similar butchering activities as at other Bed I sites, our results suggest they did not need the shelter of trees and thus occupied a competitive position within the predatory guild.


Assuntos
Hominidae , Animais , Meio Ambiente , Fósseis , Humanos , Paleontologia , Comportamento Predatório , Tanzânia
16.
Anat Rec (Hoboken) ; 305(8): 1829-1841, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35761765

RESUMO

The nasopharynx is a region at the nexus of several vital physiological systems, including the nasal cavity, oral cavity, braincase, middle ear, and cervical vertebrae. It has undergone pronounced morphological change over the course of tetrapod, mammalian, and human evolution. However, despite its place in evolutionary history, the nasopharynx has received relatively little attention. This special issue focuses on "the evolution, development, and functional morphology of the nasopharynx and its boundaries." Topics covered here include evolutionary developmental biology (or evo-devo), nasopharyngeal adaptions in bats, the importance of the nasopharynx and adjacent structures over the course of human evolution, normal development, middle ear morphology, clinical importance, and the study of the nasopharynx throughout history. Contributions to this special issue range among reviews and syntheses, descriptive analyses, phylogenetic analysis, traditional morphometrics, three-dimensional geometric morphometrics, and computational fluid dynamics. Here, we discuss the central importance of the nasopharynx as can be seen through vertebrate paleontology and comparative morphology. It is via the composite evolutionary history of the nasopharyngeal boundaries that our origins may be better understood, starting with the derivation of the choanae from the median olfactory pit of jawless fish nearly half a billion years ago to the basicranial flexion and facial reduction that distinguish Homo sapiens from all other living mammals. Indeed, the nasopharynx must be acknowledged for its importance in the processes of encephalization and acquisition of speech that have become the hallmark of our species.


Assuntos
Evolução Biológica , Paleontologia , Animais , Humanos , Mamíferos , Nasofaringe , Filogenia , Base do Crânio/anatomia & histologia
17.
Science ; 376(6597): eabl8316, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35653459

RESUMO

The long neck of the giraffe has been held as a classic example of adaptive evolution since Darwin's time. Here we report on an unusual fossil giraffoid, Discokeryx xiezhi, from the early Miocene, which has an unusual disk-shaped headgear and the most complicated head-neck joints in known mammals. The distinctive morphology and our finite element analyses indicate an adaptation for fierce head-butting behavior. Tooth enamel isotope data suggest that D. xiezhi occupied a niche different from that of other herbivores, comparable to the characteristic high-level browsing niche of modern giraffes. The study shows that giraffoids exhibit a higher headgear diversity than other ruminants and that living in specific ecological niches may have fostered various intraspecific combat behaviors that resulted in extreme head-neck morphologies in different giraffoid lineages.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Girafas , Cabeça , Pescoço , Seleção Sexual , Animais , Fósseis , Girafas/anatomia & histologia , Cabeça/anatomia & histologia , Pescoço/anatomia & histologia , Paleontologia
18.
Curr Biol ; 32(11): 2494-2504.e5, 2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35537455

RESUMO

Little is known about the spatiotemporal dynamics of gray wolves in the Pleistocene across low-latitude regions of Eurasia. In Japan, a small-bodied endemic subspecies of Japanese wolves existed and went extinct in the early 1900s. The fossil record indicates that a giant wolf, which reached 70 cm in body height, inhabited Japan during the Pleistocene, but its evolutionary relationship, if any, with the Japanese wolf remains uncertain. Here, to reveal the genetic origin of the Japanese wolf, we analyzed ancient DNA from remains (recovered in Japan) of one Pleistocene wolf that lived 35,000 years ago and one Holocene wolf from 5,000 years ago. The analysis of the mitochondrial DNA revealed that the Pleistocene wolf was not part of the Japanese wolf clade but rather an earlier-diverging lineage. The analysis of the nuclear DNA of the Holocene Japanese wolf revealed that it was an admixture of the Japanese Pleistocene wolf and continental wolf lineages. These findings suggest that the Japanese wolf originated via waves of colonization of multiple Pleistocene wolf populations at 57-35 and 37-14 ka, respectively, followed by interpopulation hybridization.


Assuntos
Lobos , Animais , DNA Mitocondrial/genética , Genômica , Japão , Paleontologia , Filogenia , Lobos/anatomia & histologia , Lobos/genética
19.
Nat Ecol Evol ; 6(7): 832-834, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35577985

Assuntos
Fósseis , Paleontologia
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