The ancient fossils are formed by the ancient animals and plants after a long geological period and geological processes. They have witnessed the history of the earth and recorded the information of the evolution of the earth’s ecological environment; Meteorites traveling in the solar system for a long time with the abrasion of nuclear reactions and atmosphere of the universe, have formed a unique shape and texture. They recorded the original information about the formation and evolution of out space. The analysis of the ancient fossils composition is the scientific basis for the study of the origin and evolution of the earth; the meteorites as rock sample from outer space are gifts from nature. They are extremely valuable and rare; the analysis of the composition of meteorites can provide a better foundation for the development of the foreign planet exploration and the development of the celestial chemistry. In this paper, the method of sample dissolution was selected and optimized. The final choice of nitric acid, hydrofluoric acid and perchloric acid as the mixed reagent, a microwave digestion method was used in treatment of ancient fossil samples; The aqua regia, nitric acid, hydrofluoric acid and perchloric acid as the mixed reagent, both microwave digestion method and wet digestion method were used in treatment of meteorite samples. Inductively coupled plasma atomic emission spectrometry (ICP-AES) was used to determine three different ancient fossil samples and three meteorite samples. And the content of same elements was compared. Analysis results show that the ancient fossils and meteorites contain Pb, Hg, Ge, Fe, Ni, Cu, Co, Mn and other heavy metal elements as well as part of the rare earth element. The standard addition recovery of the method was between 98.2%~106%, and the relative standard deviation was less than 2.12%. The method had high sensitivity, accuracy and precision.
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Curr Biol
January 2025
Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK.
Dinosaurs dominated Mesozoic terrestrial ecosystems for ∼160 million years, but their biogeographic origin remains poorly understood. The earliest unequivocal dinosaur fossils appear in the Carnian (∼230 Ma) of southern South America and Africa, leading most authors to propose southwestern Gondwana as the likely center of origin. However, the high taxonomic and morphological diversity of these earliest assemblages suggests a more ancient evolutionary history that is currently unsampled.
View Article and Find Full Text PDFSyst Biol
January 2025
Simon F. S. Li Marine Science Laboratory, School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Obtaining a timescale for bacterial evolution is crucial to understand early life evolution but is difficult owing to the scarcity of bacterial fossils. Here, we introduce multiple new time constraints to calibrate bacterial evolution based on ancient symbiosis. This idea is implemented using a bacterial tree constructed with genes found in the mitochondrial lineages phylogenetically embedded within Proteobacteria.
View Article and Find Full Text PDFGenome Biol Evol
January 2025
Institut Català de Paleontologia Miquel Crusafont (ICP-CERCA), Universitat Autònoma de Barcelona, Edifici ICTA-ICP, Cerdanyola del Vallès, Barcelona, Spain; Unidad de Paleobiología, ICP-CERCA, Unidad Asociada al CSIC por el IBE UPF-CSIC, Cerdanyola del Vallès, Barcelona, Spain; Departament de Medicina i Ciències de la Vida, Institut de Biologia Evolutiva (CSIC-UPF), Universitat Pompeu Fabra, Barcelona, Spain.
Ancient tooth enamel, and to some extent dentin and bone, contain characteristic peptides that persist for long periods of time. In particular, peptides from the enamel proteome (enamelome) have been used to reconstruct the phylogenetic relationships of fossil taxa. However, the enamelome is based on only about 10 genes, whose protein products undergo fragmentation in vivo and post mortem.
View Article and Find Full Text PDFAnn Bot
January 2025
Département de Biologie, Université Laval, Canada.
Background And Aims: Resolving the phylogeny of hornworts is critical in understanding the evolution of key morphological characters that are unique to the group, including the pyrenoid. Extensive phylogenomic analyses have revealed unexpected complexities in the placement of Leiosporoceros, the previously identified sister taxon to other hornworts. We explore the role of incomplete lineage sorting (ILS) and ancient reticulation in resolving interrelationships and comprehending the diversification and evolutionary processes within hornworts.
View Article and Find Full Text PDFNat Commun
January 2025
Polar Terrestrial Environmental Systems, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany.
During the Pleistocene-Holocene transition, the dominant mammoth steppe ecosystem across northern Eurasia vanished, in parallel with megafauna extinctions. However, plant extinction patterns are rarely detected due to lack of identifiable fossil records. Here, we introduce a method for detection of plant taxa loss at regional (extirpation) to potentially global scale (extinction) and their causes, as determined from ancient plant DNA metabarcoding in sediment cores (sedaDNA) from lakes in Siberia and Alaska over the past 28,000 years.
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