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1.
Sci Rep ; 14(1): 9804, 2024 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684726

RESUMEN

Interest continues to grow in Arctic megafaunal ecological engineering, but, since the mass extinction of megafauna ~ 12-15 ka, key physiographic variables and available forage continue to change. Here we sought to assess the extent to which contemporary Arctic ecosystems are conducive to the rewilding of megaherbivores, using a woolly mammoth (M. primigenius) proxy as a model species. We first perform a literature review on woolly mammoth dietary habits. We then leverage Oak Ridge National Laboratories Distributive Active Archive Center Global Aboveground and Belowground Biomass Carbon Density Maps to generate aboveground biomass carbon density estimates in plant functional types consumed by the woolly mammoth at 300 m resolution on Alaska's North Slope. We supplement these analyses with a NASA Arctic Boreal Vulnerability Experiment dataset to downgrade overall biomass estimates to digestible levels. We further downgrade available forage by using a conversion factor representing the relationship between total biomass and net primary productivity (NPP) for arctic vegetation types. Integrating these estimates with the forage needs of woolly mammoths, we conservatively estimate Alaska's North Slope could support densities of 0.0-0.38 woolly mammoth km-2 (mean 0.13) across a variety of habitats. These results may inform innovative rewilding strategies.


Asunto(s)
Biomasa , Ecosistema , Mamuts , Regiones Árticas , Animales , Alaska , Carbono/análisis , Carbono/metabolismo
2.
PLoS One ; 19(4): e0299689, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38656936

RESUMEN

The use of elephant ivory as a commodity is a factor in declining elephant populations. Despite recent worldwide elephant ivory trade bans, mammoth ivory trade remains unregulated. This complicates law enforcement efforts, as distinguishing between ivory from extant and extinct species requires costly, destructive and time consuming methods. Elephant and mammoth ivory mainly consists of dentine, a mineralized connective tissue that contains an organic collagenous component and an inorganic component of calcium phosphate minerals, similar in structure to hydroxyapatite crystals. Raman spectroscopy is a non-invasive laser-based technique that has previously been used for the study of bone and mineral chemistry. Ivory and bone have similar biochemical properties, making Raman spectroscopy a promising method for species identification based on ivory. This study aimed to test the hypothesis that it is possible to identify differences in the chemistry of mammoth and elephant ivory using Raman spectroscopy. Mammoth and elephant tusks were obtained from the Natural History Museum in London, UK. Included in this study were eight samples of ivory from Mammuthus primigenius, two samples of carved ivory bangles from Africa (Loxodonta species), and one cross section of a tusk from Elephas maximus. The ivory was scanned using an inVia Raman micro spectrometer equipped with a x50 objective lens and a 785nm laser. Spectra were acquired using line maps and individual spectral points were acquired randomly or at points of interest on all samples. The data was then analysed using principal component analysis (PCA) with use of an in-house MATLAB script. Univariate analysis of peak intensity ratios of phosphate to amide I and III peaks, and carbonate to phosphate peaks showed statistical differences (p<0.0001) in the average peak intensity ratios between Mammuthus primigenius, Loxodonta spp. and Elephas maximus. Full width at half maximum hight (FWHM)analysis of the phosphate peak demonstrated higher crystal maturity of Mammuthus primigenius compared to living elephant species. The results of the study have established that spectra acquired by Raman spectroscopy can be separated into distinct classes through PCA. In conclusion, this study has shown that well-preserved mammoth and elephant ivory has the potential to be characterized using Raman spectroscopy, providing a promising method for species identification. The results of this study will be valuable in developing quick and non-destructive methods for the identification of ivory, which will have direct applications in archaeology and the regulation of international trade.


Asunto(s)
Elefantes , Espectrometría Raman , Animales , Espectrometría Raman/métodos , Mamuts , Extinción Biológica , Análisis de Componente Principal , Conservación de los Recursos Naturales/métodos , Animales Salvajes , Fósiles , Comercio de Vida Silvestre
4.
Environ Microbiol ; 26(2): e16589, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38356049

RESUMEN

Ancient environmental samples, including permafrost soils and frozen animal remains, represent an archive with microbial communities that have barely been explored. This yet unexplored microbial world is a genetic resource that may provide us with new evolutionary insights into recent genomic changes, as well as novel metabolic pathways and chemistry. Here, we describe Actinomycetota Micromonospora, Oerskovia, Saccharopolyspora, Sanguibacter and Streptomyces species were successfully revived and their genome sequences resolved. Surprisingly, the genomes of these bacteria from an ancient source show a large phylogenetic distance to known strains and harbour many novel biosynthetic gene clusters that may well represent uncharacterised biosynthetic potential. Metabolic profiles of the strains display the production of known molecules like antimycin, conglobatin and macrotetrolides, but the majority of the mass features could not be dereplicated. Our work provides insights into Actinomycetota isolated from an ancient source, yielding unexplored genomic information that is not yet present in current databases.


Asunto(s)
Actinomycetales , Mamuts , Streptomyces , Animales , Filogenia , Genómica , Streptomyces/genética , Heces
5.
Sci Adv ; 10(3): eadk0818, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38232155

RESUMEN

Woolly mammoths in mainland Alaska overlapped with the region's first people for at least a millennium. However, it is unclear how mammoths used the space shared with people. Here, we use detailed isotopic analyses of a female mammoth tusk found in a 14,000-year-old archaeological site to show that she moved ~1000 kilometers from northwestern Canada to inhabit an area with the highest density of early archaeological sites in interior Alaska until her death. DNA from the tusk and other local contemporaneous archaeological mammoth remains revealed that multiple mammoth herds congregated in this region. Early Alaskans seem to have structured their settlements partly based on mammoth prevalence and made use of mammoths for raw materials and likely food.


Asunto(s)
Mamuts , Humanos , Animales , Femenino , Recién Nacido , Mamuts/genética , ADN , Canadá , Alaska , Fósiles
6.
Curr Med Res Opin ; 40(2): 199-207, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38078866

RESUMEN

INTRODUCTION: For patients with triple-class exposed/refractory multiple myeloma (TCE/R MM), prognosis is poor and effective treatment options are limited. Elranatamab is a novel B-cell maturation antigen (BCMA)- and CD3-directed bispecific antibody which was approved by the US Food and Drug Administration in August 2023 and demonstrated safety and efficacy in patients with TCE/R MM in the phase 2, single-arm MagnetisMM-3 trial (NCT04649359). To compare the effectiveness of elranatamab vs physician's choice of treatment (PCT) in the absence of head-to-head comparative data, a matching-adjusted indirect comparison (MAIC) was conducted. METHODS: Individual patient data from MagnetisMM-3 (Cohort A [BCMA-naïve] N = 123, 14.7 months of follow-up) were reweighted to match published summary data from two real-world studies of PCT in patients with TCE/R MM (LocoMMotion and MAMMOTH) using a propensity score-type logistic regression. Unanchored MAIC analyses were conducted according to National Institute for Health and Care Excellence (NICE) Decision Support Unit (DSU) 18 guidance. RESULTS: Compared with PCT in LocoMMotion, elranatamab was associated with a significantly higher objective response rate (ORR rate difference: 37.52; 95% CI 26.20-48.83; odds ratio: 4.85; 95% CI 2.85-8.23) and complete or stringent complete response rate (≥CR rate difference: 42.29; 95% CI 31.84-52.74; odds ratio: 184.01; 95% CI 24.66-1372.86), longer progression-free survival (PFS HR 0.32; 95% CI 0.20-0.49), and overall survival (OS HR 0.62; 95% CI 0.40-0.94). Compared with PCT in MAMMOTH, elranatamab was associated with significantly higher ORR (rate difference: 28.14; 95% CI 16.77-39.52; odds ratio: 3.24; 95% CI 1.98-5.32) and ≥ CR (rate difference: 26.22; 95% CI 16.40-36.05; odds ratio: 5.48; 95% CI 2.88-10.44), as well as longer PFS (HR 0.25; 95% CI 0.17-0.37) and OS (HR 0.49; 95% CI 0.33-0.71). Sensitivity analysis results were consistent with the base case. CONCLUSION: In the MAIC, elranatamab was consistently associated with improved rates and depth of response and significantly longer PFS and OS versus PCT in LocoMMotion and MAMMOTH.


Asunto(s)
Mamuts , Mieloma Múltiple , Médicos , Humanos , Animales , Mieloma Múltiple/tratamiento farmacológico , Antígeno de Maduración de Linfocitos B/uso terapéutico , Resultado del Tratamiento
7.
J Morphol ; 284(9): e21626, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37585227

RESUMEN

Extinct woolly rhinoceroses were iconic representatives of the Late Pleistocene mammoth fauna of Eurasia. These animals were characterized by two huge keratinous horns. In adults, the length of the nasal horn often exceeded one meter. The nasal horn of Coelodonta was characterized by an unusual feature for rhinoceroses-the width of its base was considerably narrower than the width of the rugosity area on the nasal bones of the skull. In this study, a new discovery of woolly rhinoceros' nasal horn in the permafrost of Yakutia is described. This specimen shows that the shape of the base of the woolly rhino's nasal horn corresponds well to the shape (length and width) of the nasal rugosity area. The base of the nasal horn of Coelodonta was markedly elongated anteroposteriorly compared to extant rhinoceroses. Its length was about 150% of the width. We therefore suggest that the narrower shape of the nasal horn base in the majority of previously found specimens was associated with secondary damage after burial caused by maceration.


Asunto(s)
Mamuts , Hielos Perennes , Animales , Cabeza , Nariz , Perisodáctilos/anatomía & histología , Cráneo , Mamuts/anatomía & histología
8.
Curr Biol ; 33(16): R870-R872, 2023 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-37607485

RESUMEN

Twenty-two woolly mammoth genomes have been compared to those of living elephants, identifying genes under strong evolutionary pressure in mammoths, including genes associated with curly, wiry, thick, bushy, coarse, uncombable and (of course) woolly hair.


Asunto(s)
Mamuts , Animales , Mamuts/genética , Evolución Biológica
9.
Nature ; 617(7961): 533-539, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37138076

RESUMEN

Hormones in biological media reveal endocrine activity related to development, reproduction, disease and stress on different timescales1. Serum provides immediate circulating concentrations2, whereas various tissues record steroid hormones accumulated over time3,4. Hormones have been studied in keratin, bones and teeth in modern5-8 and ancient contexts9-12; however, the biological significance of such records is subject to ongoing debate10,13-16, and the utility of tooth-associated hormones has not previously been demonstrated. Here we use liquid chromatography with tandem mass spectrometry paired with fine-scale serial sampling to measure steroid hormone concentrations in modern and fossil tusk dentin. An adult male African elephant (Loxodonta africana) tusk shows periodic increases in testosterone that reveal episodes of musth17-19, an annually recurring period of behavioural and physiological changes that enhance mating success20-23. Parallel assessments of a male woolly mammoth (Mammuthus primigenius) tusk show that mammoths also experienced musth. These results set the stage for wide-ranging studies using steroids preserved in dentin to investigate development, reproduction and stress in modern and extinct mammals. Because dentin grows by apposition, resists degradation, and often contains growth lines, teeth have advantages over other tissues that are used as records of endocrine data. Given the low mass of dentin powder required for analytical precision, we anticipate dentin-hormone studies to extend to smaller animals. Thus, in addition to broad applications in zoology and palaeontology, tooth hormone records could support medical, forensic, veterinary and archaeological studies.


Asunto(s)
Elefantes , Fósiles , Mamuts , Testosterona , Diente , Animales , Masculino , Elefantes/anatomía & histología , Elefantes/metabolismo , Mamuts/anatomía & histología , Mamuts/metabolismo , Esteroides/análisis , Esteroides/metabolismo , Testosterona/análisis , Testosterona/metabolismo , Diente/química , Diente/metabolismo , Dentina/química , Dentina/metabolismo
10.
Mol Ecol ; 32(11): 2689-2691, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37212188

RESUMEN

When one thinks of the field of ancient DNA it conjures images of extinct megafauna, from mammoths and woolly rhinos, through to the giant, flightless elephant bird (but hopefully not dinosaurs - despite the pervasive idea of 'dino DNA' from Jurassic park). These taxa have fascinating evolutionary histories, and their extinction stories need to be told. At the other end of the vertebrate scale, however, is the often neglected 'small stuff' - lizards, frogs, and other herpetofauna. But here's the rub - extracting DNA from the bones of this 'small stuff' is not only difficult, it often destroys the sample. In this issue, Scarsbrook et al. (2023) describe a new way to study the ancient (or historical) DNA of small vertebrates that is minimally destructive. The authors use the method to reconstruct the dynamic evolutionary history of New Zealand geckos and make new insights into how remnant populations should be managed. This work provides some key insights into New Zealand geckos but also opens up opportunities of biomolecular research on the smallest of vouchered vertebrate samples held within museum collections.


Asunto(s)
ADN Antiguo , Mamuts , Animales , Sudor , ADN/genética , Evolución Biológica , Aves/genética , Mamuts/genética , Fósiles , Filogenia
11.
Curr Biol ; 33(9): 1753-1764.e4, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-37030294

RESUMEN

Ancient genomes provide a tool to investigate the genetic basis of adaptations in extinct organisms. However, the identification of species-specific fixed genetic variants requires the analysis of genomes from multiple individuals. Moreover, the long-term scale of adaptive evolution coupled with the short-term nature of traditional time series data has made it difficult to assess when different adaptations evolved. Here, we analyze 23 woolly mammoth genomes, including one of the oldest known specimens at 700,000 years old, to identify fixed derived non-synonymous mutations unique to the species and to obtain estimates of when these mutations evolved. We find that at the time of its origin, the woolly mammoth had already acquired a broad spectrum of positively selected genes, including ones associated with hair and skin development, fat storage and metabolism, and immune system function. Our results also suggest that these phenotypes continued to evolve during the last 700,000 years, but through positive selection on different sets of genes. Finally, we also identify additional genes that underwent comparatively recent positive selection, including multiple genes related to skeletal morphology and body size, as well as one gene that may have contributed to the small ear size in Late Quaternary woolly mammoths.


Asunto(s)
Mamuts , Animales , Mamuts/genética , Análisis de Secuencia de ADN , Genómica/métodos , Genoma/genética , Mutación , Fósiles , Evolución Molecular
13.
PLoS One ; 17(12): e0278609, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36459531

RESUMEN

Genetic information provides insights into the exome, genome, epigenetics and structural organisation of the organism. Given the enormous amount of genetic information, scientists are able to perform mammoth tasks to improve the standard of health care such as determining genetic influences on outcome of allogeneic transplantation. Cloud based computing has increasingly become a key choice for many scientists, engineers and institutions as it offers on-demand network access and users can conveniently rent rather than buy all required computing resources. With the positive advancements of cloud computing and nanopore sequencing data output, we were motivated to develop an automated and scalable analysis pipeline utilizing cloud infrastructure in Microsoft Azure to accelerate HLA genotyping service and improve the efficiency of the workflow at lower cost. In this study, we describe (i) the selection process for suitable virtual machine sizes for computing resources to balance between the best performance versus cost effectiveness; (ii) the building of Docker containers to include all tools in the cloud computational environment; (iii) the comparison of HLA genotype concordance between the in-house manual method and the automated cloud-based pipeline to assess data accuracy. In conclusion, the Microsoft Azure cloud based data analysis pipeline was shown to meet all the key imperatives for performance, cost, usability, simplicity and accuracy. Importantly, the pipeline allows for the on-going maintenance and testing of version changes before implementation. This pipeline is suitable for the data analysis from MinION sequencing platform and could be adopted for other data analysis application processes.


Asunto(s)
Mamuts , Secuenciación de Nanoporos , Animales , Nube Computacional , Análisis de Datos , Exactitud de los Datos
15.
Nature ; 612(7938): E1-E3, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36450914
16.
Science ; 378(6621): 696-697, 2022 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-36395232

RESUMEN

Paleontologists are urged to take a stand against a market that may provide cover for continued poaching.


Asunto(s)
Conservación de los Recursos Naturales , Crimen , Elefantes , Mamuts , Animales , Fósiles
18.
Med Sci (Paris) ; 38(5): 480-483, 2022 May.
Artículo en Francés | MEDLINE | ID: mdl-35608473

RESUMEN

Reports of a mammoth cloning project on-going under George Church's supervision appear periodically in the press. Close examination of the available evidence indicates that there is indeed such a project (carried out in a company called "Colossal"), but the aim is actually to modify the Asian elephant's genome so that the resulting animal displays some significant cold-adaptation traits, could theoretically be reintroduced into Siberia, and would then (also theoretically) modify the biotope towards its initial state of a steppe rather than a tundra. This endeavour seems largely unfeasible, but it may trigger important methodological advances that probably explain its ability to attract significant capital investment.


Asunto(s)
Mamuts , Animales , Decepción , Genoma , Humanos , Mamuts/genética , Siberia
19.
Amino Acids ; 54(6): 935-954, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35434776

RESUMEN

The recent paleoproteomic studies, including paleo-metaproteomic analyses, improved our understanding of the dietary of ancient populations, the characterization of past human diseases, the reconstruction of the habitat of ancient species, but also provided new insights into the phylogenetic relationships between extant and extinct species. In this respect, the present work reports the results of the metaproteomic analysis performed on the middle part of a trunk, and on the portion of a trunk tip tissue of two different woolly mammoths some 30,000 years old. In particular, proteins were extracted by applying EVA (Ethylene-Vinyl Acetate studded with hydrophilic and hydrophobic resins) films to the surface of these tissues belonging to two Mammuthus primigenus specimens, discovered in two regions located in the Russian Far East, and then investigated via a shotgun MS-based approach. This approach allowed to obtain two interesting results: (i) an indirect description of the habitat of these two mammoths, and (ii) an improved characterization of the collagen type I, alpha-1 and alpha-2 chains (col1a1 and col1a2). Sequence characterization of the col1a1 and col1a2 highlighted some differences between M. primigenius and other Proboscidea together with the identification of three (two for col1a1, and one for col1a2) potentially diagnostic amino acidic mutations that could be used to reliably distinguish the Mammuthus primigenius with respect to the other two genera of elephantids (i.e., Elephas and Loxodonta), and the extinct American mastodon (i.e., Mammut americanum). The results were validated through the level of deamidation and other diagenetic chemical modifications of the sample peptides, which were used to discriminate the "original" endogenous peptides from contaminant ones. The data have been deposited to the ProteomeXchange with identifier < PXD029558 > .


Asunto(s)
Mamuts , Animales , Humanos , Recién Nacido , Colágeno Tipo I/genética , Ecosistema , Fósiles , Mamuts/genética , Espectrometría de Masas , Filogenia , Proteómica/métodos , Tecnología
20.
Sci Rep ; 12(1): 6796, 2022 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-35474321

RESUMEN

The study of local extinction times, together with the associated environmental and human population changes in the last glacial termination, provides insights into the causes of mega- and microfauna extinctions. In East-Central (EC) Europe, groups of Palaeolithic humans were present throughout the last glacial maximum, but disappeared suddenly around 15,200 cal BP. In this study cave sediment profiles dated using radiocarbon techniques and a large set of mammal bones dated directly by AMS 14C were used to determine local extinction times. These were, in turn, compared to changes in the total megafauna population of EC Europe derived from coprophilous fungi, the Epigravettian population decline, quantitative climate models, pollen and plant macrofossil inferred climate, as well as to biome reconstructions. The results suggest that the population size of large herbivores decreased in the area after 17,700 cal BP, when temperate tree abundance and warm continental steppe cover both increased in the lowlands. Boreal forest expansion started around 16,200 cal BP. Cave sediments show the decline of narrow-headed vole and arctic lemming populations specifically associated with a tundra environment at the same time and the expansion of the common vole, an inhabitant of steppes. The last dated appearance of arctic lemming was at ~ 16,640 cal BP, while that of the narrow-headed vole at ~ 13,340, and the estimated extinction time of woolly mammoth was either at 13,830 (GRIWM) or 15,210 (PHASE), and reindeer at 11,860 (GRIWM) or 12,550 cal BP (PHASE). The population decline of the large herbivore fauna slightly preceded changes in terrestrial vegetation, and likely facilitated it via a reduction in the intensity of grazing and the concomitant accumulation of plant biomass. Furthermore, it is possible to conclude that the Late Epigravettian population had high degree of quarry-fidelity; they left the basin when these mammals vanished.


Asunto(s)
Ecosistema , Mamuts , Animales , Arvicolinae , Clima , Humanos , Mamíferos , Tundra
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