Displaying publications 1 - 20 of 38 in total

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  1. Curnoe D, Datan I, Zhao JX, Leh Moi Ung C, Aubert M, Sauffi MS, et al.
    PLoS One, 2018;13(6):e0196633.
    PMID: 29874227 DOI: 10.1371/journal.pone.0196633
    The skeletal remains of Late Pleistocene-early Holocene humans are exceptionally rare in island Southeast Asia. As a result, the identity and physical adaptations of the early inhabitants of the region are poorly known. One archaeological locality that has historically been important for understanding the peopling of island Southeast Asia is the Niah Caves in the northeast of Borneo. Here we present the results of direct Uranium-series dating and the first published descriptions of three partial human mandibles from the West Mouth of the Niah Caves recovered during excavations by the Harrissons in 1957. One of them (mandible E/B1 100") is somewhat younger than the 'Deep Skull' with a best dating estimate of c30-28 ka (at 2σ), while the other two mandibles (D/N5 42-48" and E/W 33 24-36") are dated to a minimum of c11.0-10.5 ka (at 2σ) and c10.0-9.0 ka (at 2σ). Jaw E/B1 100" is unusually small and robust compared with other Late Pleistocene mandibles suggesting that it may have been ontogenetically altered through masticatory strain under a model of phenotypic plasticity. Possible dietary causes could include the consumption of tough or dried meats or palm plants, behaviours which have been documented previously in the archaeological record of the Niah Caves. Our work suggests a long history back to before the LGM of economic strategies involving the exploitation of raw plant foods or perhaps dried and stored meat resources. This offers new insights into the economic strategies of Late Pleistocene-early Holocene hunter-gatherers living in, or adjacent to, tropical rainforests.
    Matched MeSH terms: Fossils*
  2. Matsumura H, Zuraina M
    Am. J. Phys. Anthropol., 1999 Jul;109(3):327-40.
    PMID: 10407463
    A nearly complete human skeleton dating to the Early Holocene (epi-Paleolithic culture) excavated from Gua Gunung Runtuh, Malaysia, is described. Cranial, dental, and limb bone measurements are recorded on the skeleton, and compared with early and modern skeletal samples from Southeast Asia and Australia. The comparisons demonstrate that the Gua Gunung specimen is most similar to Australian Aborigines in dental and limb measurements, while the cranial measurements indicate a close affinity to Mesolithic samples from Malaysia and Flores. These findings further suggest that the Gua Gunung skeleton, as well as other fossils from Tabon and Niah, are representative of an early group of people who occupied Sundaland during the late Pleistocene, and may be the ancestors of Australian Aborigines. Some of the dental and limb bone measurements exhibited by the ancestors persist in Southeast Asian populations until the early Holocene. Differences in cranial traits have, however, accumulated since the late Pleistocene in Australian Aborigines and early Southeast Asian peoples.
    Matched MeSH terms: Fossils*
  3. Curnoe D, Datan I, Goh HM, Sauffi MS
    J Hum Evol, 2019 02;127:133-148.
    PMID: 30777354 DOI: 10.1016/j.jhevol.2018.12.008
    The skeletal remains of Pleistocene anatomically modern humans are rare in island Southeast Asia. Moreover, continuing doubts over the dating of most of these finds has left the arrival time for the region's earliest inhabitants an open question. The unique biogeography of island Southeast Asia also raises questions about the physical and cultural adaptations of early anatomically modern humans, especially within the setting of rainforest inhabitation. Within this context the Deep Skull from the West Mouth of the Niah Caves continues to figure prominently owing to its relative completeness and the greater certainty surrounding its geological age. Recovered along with this partial cranium in 1958 were several postcranial bones including a partial femur which until now has received little attention. Here we provide a description and undertake a comparison of the Deep Skull femur finding it to be very small in all of its cross-sectional dimensions. We note a number of size and shape similarities to the femora of Indigenous Southeast Asians, especially Aeta people from the Philippines. We estimate its stature to have been roughly 145-146 cm and body mass around 35 kg, confirming similarities to Aeta females. Its extreme gracility indicated by low values for a range of biomechanical parameters taken midshaft meets expectations for a very small (female) Paleolithic East Asian. Interestingly, the second moment of area about the mediolateral axis is enlarged relative to the second moment of area about the anteroposterior axis, which could potentially signal a difference in activity levels or lifestyle compared with other Paleolithic femora. However, it might also be the result of sexual dimorphism in these parameters as well as possibly reflecting changes associated with aging.
    Matched MeSH terms: Fossils/anatomy & histology*
  4. Basir Jasin
    Sains Malaysiana, 2015;44:217-223.
    Posidonomya is common in the Kubang Pasu and Singa Formations in northwest Peninsular Malaysia. It was discovered from the red mudstone layers (redbeds) in many localities in Langkawi Islands, Perlis and Kedah. Previous studies suggested that the age of Posidonomya ranged from Middle Devonian to Carboniferous. Posidonomya beds in Kedah and Perlis are located above the Tournaisian radiolarian chert layers. The age of Posidonomya from Peninsular Malaysia is comparable to those of Europe, Morocco, Turkey and South China which range from Tournaisian to Serpukhovian, Early Carboniferous. The fossil specimens exhibit morphological features closely related to Posidonomya becheri Bronn. Two taxa were identified namely Posidonomya becheri Bronn and Posidonomya cf. kochi (von Koenen). The occurrence of Posidonomya indicates that the age of the lower part of the Kubang Pasu and Singa Formations is Early Carboniferous. Its geographic distribution formed a wide paleobiogeographic province in the Paleo-Tethys. The province was located in the warm tropical-subtropical climatic zone. Therefore, Posidonomya can be a good indicator for warm climate. Its wide distribution and short stratigraphic range make it a good index fossil for the Early Carboniferous.
    Matched MeSH terms: Fossils
  5. Veera Singham G, Othman AS, Lee CY
    PLoS One, 2017;12(11):e0186690.
    PMID: 29186140 DOI: 10.1371/journal.pone.0186690
    Dispersal of soil-dwelling organisms via the repeatedly exposed Sunda shelf through much of the Pleistocene in Southeast Asia has not been studied extensively, especially for invertebrates. Here we investigated the phylogeography of an endemic termite species, Macrotermes gilvus (Hagen), to elucidate the spatiotemporal dynamics of dispersal routes of terrestrial fauna in Pleistocene Southeast Asia. We sampled 213 termite colonies from 66 localities throughout the region. Independently inherited microsatellites and mtDNA markers were used to infer the phylogeographic framework of M. gilvus. Discrete phylogeographic analysis and molecular dating based on fossil calibration were used to infer the dynamics of M. gilvus dispersal in time and space across Southeast Asia. We found that the termite dispersal events were consistently dated within the Pleistocene time frame. The dispersal pattern was multidirectional, radiating eastwards and southwards out of Indochina, which was identified as the origin for dispersal events. We found no direct dispersal events between Sumatra and Borneo despite the presence of a terrestrial connection between them during the Pleistocene. Instead, central Java served as an important link allowing termite colonies to be established in Borneo and Sumatra. Our findings support the hypothesis of a north-south dispersal corridor in Southeast Asia and suggest the presence of alternative dispersal routes across Sundaland during the Pleistocene. For the first time, we also propose that a west-east dispersal through over-water rafting likely occurred across the Pleistocene South China Sea. We found at least two independent entry routes for terrestrial species to infiltrate Sumatra and Borneo at different times.
    Matched MeSH terms: Fossils*
  6. Heinrichs J, Scheben A, Bechteler J, Lee GE, Schäfer-Verwimp A, Hedenäs L, et al.
    PLoS One, 2016;11(5):e0156301.
    PMID: 27244582 DOI: 10.1371/journal.pone.0156301
    Cambay amber originates from the warmest period of the Eocene, which is also well known for the appearance of early angiosperm-dominated megathermal forests. The humid climate of these forests may have triggered the evolution of epiphytic lineages of bryophytes; however, early Eocene fossils of bryophytes are rare. Here, we present evidence for lejeuneoid liverworts and pleurocarpous mosses in Cambay amber. The preserved morphology of the moss fossil is inconclusive for a detailed taxonomic treatment. The liverwort fossil is, however, distinctive; its zig-zagged stems, suberect complicate-bilobed leaves, large leaf lobules, and small, deeply bifid underleaves suggest a member of Lejeuneaceae subtribe Lejeuneinae (Harpalejeunea, Lejeunea, Microlejeunea). We tested alternative classification possibilities by conducting divergence time estimates based on DNA sequence variation of Lejeuneinae using the age of the fossil for corresponding age constraints. Consideration of the fossil as a stem group member of Microlejeunea or Lejeunea resulted in an Eocene to Late Cretaceous age of the Lejeuneinae crown group. This reconstruction is in good accordance with published divergence time estimates generated without the newly presented fossil evidence. Balancing available evidence, we describe the liverwort fossil as the extinct species Microlejeunea nyiahae, representing the oldest crown group fossil of Lejeuneaceae.
    Matched MeSH terms: Fossils/anatomy & histology; Fossils/history
  7. Chan YH, Syed Abdul Rahman SNF, Lahuri HM, Khalid A
    Environ Pollut, 2021 Mar 01;278:116843.
    PMID: 33711630 DOI: 10.1016/j.envpol.2021.116843
    Carbon monoxide (CO) is a highly valuable component of syngas which could be used to synthesize various chemicals and fuels. Conventionally, syngas is derived from fossil-based natural gas and coal which are non-renewable. To curb the problem, CO2 gasification offers a win-win solution in which CO2 is converted with wastes to CO, achieving carbon emission mitigation and addressing waste disposal issue simultaneously. In this review, gasification of various wastes by CO2 with particular focus given to generation of CO-rich syngas is presented and critically discussed. This includes the effects of operating parameters (temperature, pressure and physicochemical properties of feedstocks) and advanced CO2 gasification techniques (catalytic CO2 gasification, CO2 co-gasification and microwave-driven CO2 gasification). Furthermore, associated technological challenges are highlighted and way forward in this field are proposed.
    Matched MeSH terms: Fossils
  8. Liu J, Andersson A, Zhong G, Geng X, Ding P, Zhu S, et al.
    Sci Total Environ, 2020 Jul 03;744:140359.
    PMID: 32688001 DOI: 10.1016/j.scitotenv.2020.140359
    Black Carbon (BC) deteriorates air quality and contributes to climate warming, yet its regionally- and seasonally-varying emission sources are poorly constrained. Here we employ natural abundance radiocarbon (14C) measurements of BC intercepted at a northern Malaysia regional receptor site, Bachok, to quantify the relative biomass vs. fossil source contributions of atmospheric BC, in a first year-round study for SE Asia (December 2015-December 2016). The annual average 14C signature suggests as large contributions from biomass burning as from fossil fuel combustion. This is similar to findings from analogous measurements at S Asian receptors sites (~50% biomass burning), while E Asia sites are dominated by fossil emission (~20% biomass burning). The 14C-based source fingerprinting of BC in the dry spring season in SE Asia signals an even more elevated biomass burning contribution (~70% or even higher), presumably from forest, shrub and agricultural fires. This is consistent with this period showing also elevated ratio of organic carbon to BC (up from ~5 to 30) and estimates of BC emissions from satellite fire data. Hence, the present study emphasizes the importance of mitigating dry season vegetation fires in SE Asia.
    Matched MeSH terms: Fossils
  9. Norha Abdul Hadi, Mawar Hasyikin Abu Seman, Madhiyah Yahaya Bermakai
    MyJurnal
    Derivation of activated carbon from biomass wastes for energy storage applications such as fuel cells and supercapacitors are attracting wide attractions as the world is now demand for other sustainable energy that can help to explore new technologies especially for energy conversion and storage. This is important because the world now is facing a rapid depletion of fossil energy. In this review, an outline of recent trends towards biomass-derived specifically from fruit-based biomass wastes is explained in a holistic manner. Thanks to their high carbon content, high specific surface area and developed porous structure, biomass-derived chars can be treated and converted into carbon. The performance of activated carbon in terms of Brunette Emmet Teller (BET) surface area, micropore volume, total pore volume and specific capacitance has been reported. This review showed that higher BET surface will contribute to higher pore volume in the activated carbon that makes them good candidates for the fabrication of electrodes in supercapacitor applications. This study was focused on providing a detailed comparison of published studies that utilized different physical and chemical routes and their effect of modification such as various activation temperatures and the ratio of activating agents towards the performance of the activated carbon under different parameters. Implementing chemical routes with an ideal 600°C – 850°C and inclusion ratio might be effective to produce high performance activated carbon.
    Matched MeSH terms: Fossils
  10. Nita Salina Abu Bakar, Zal U’yun Wan Mahmood, Ahmad Saat, Abdul Kadir Ishak
    MyJurnal
    Anthropogenic airborne depositions of 210Po,
    210Pb and 210Po/210Pb in the mosses and surface soils
    collected at the vicinity of a coal-fired power plant were studied. The purpose of the study was to
    determine activity concentrations of 210Po,
    210Pb and 210Po/210Pb for assessing their variation
    accumulation in the mosses and surface soils collected at the vicinity of a coal-fired power plant.
    Other purposes were to determine their concentration factor (CF) in relation to track the potential
    source of those radionuclides and to identify most suitable moss species as a biological indicator
    for atmospheric deposition contaminants. In this study, different species of moss Leucobryum
    aduncum, Campylopus serratus, Syrrhopodon ciliates and Vesicularia montagnei were collected in
    May 2011 at the area around 15 km radius from Tanjung Bin coal-fired power plant located in
    Pontian, Johor. The activity concentrations of 210Po,
    210Pb and 210Po/210Pb in mosses were in the
    range of 76.81 ± 4.94 – 251.33 ± 16.33 Bq/kg dry wt., 54.37 ± 3.38 – 164.63 ± 11.64 Bq/kg dry wt.
    and 1.10 – 2.00, respectively. Meanwhile the ranges for those radionuclides in the surface soil
    were 33.53 ± 2.10 – 179.67 ± 12.15 Bq/kg dry wt., 20.55 ± 1.33 – 106.62 ± 6.64 Bq/kg dry wt. and
    1.61 – 2.44, respectively. Corresponding high ability of Leucobryum aduncum to accumulate more
    210Po and 210Pb, wide geographical distribution, most abundant and high CF, therefore, the
    findings can be concluded this species was the most suitable as a biological indicator for
    atmospheric deposition contaminants such as 210Po and 210Pb. Furthermore, it is clear the
    accumulation of 210Po and 210Pb in mosses might be supplied from various sources of atmospheric
    deposition such as coal-fired power plant operation, industrial, agriculture and fertilizer activities,
    burned fuel fossil and forest; and other potential sources. Meanwhile, the
    Matched MeSH terms: Fossils
  11. Spehar SN, Sheil D, Harrison T, Louys J, Ancrenaz M, Marshall AJ, et al.
    Sci Adv, 2018 06;4(6):e1701422.
    PMID: 29963619 DOI: 10.1126/sciadv.1701422
    Conservation benefits from understanding how adaptability and threat interact to determine a taxon's vulnerability. Recognizing how interactions with humans have shaped taxa such as the critically endangered orangutan (Pongo spp.) offers insights into this relationship. Orangutans are viewed as icons of wild nature, and most efforts to prevent their extinction have focused on protecting minimally disturbed habitat, with limited success. We synthesize fossil, archeological, genetic, and behavioral evidence to demonstrate that at least 70,000 years of human influence have shaped orangutan distribution, abundance, and ecology and will likely continue to do so in the future. Our findings indicate that orangutans are vulnerable to hunting but appear flexible in response to some other human activities. This highlights the need for a multifaceted, landscape-level approach to orangutan conservation that leverages sound policy and cooperation among government, private sector, and community stakeholders to prevent hunting, mitigate human-orangutan conflict, and preserve and reconnect remaining natural forests. Broad cooperation can be encouraged through incentives and strategies that focus on the common interests and concerns of different stakeholders. Orangutans provide an illustrative example of how acknowledging the long and pervasive influence of humans can improve strategies to preserve biodiversity in the Anthropocene.
    Matched MeSH terms: Fossils
  12. Hill N
    PLoS One, 2019;14(2):e0206023.
    PMID: 30785876 DOI: 10.1371/journal.pone.0206023
    Tropidolaemus wagleri is a species of Asian pitviper with a geographic range including Thailand, Vietnam, Malaysia, Singapore, Bruniei, parts of Indonesia, and the Philippines. Tropidolaemus is a member of the Crotalinae subfamily, within Viperidae. The genus Tropidolaemus includes five species, and was once included within the genus Trimeresurus. While some osteologic characteristics have been noted a comprehensive description of cranial elements has not been produced for T. wagleri. An in-depth description of the cranial skeleton of Tropidolaemus wagleri lays the foundation for future projects to compare and contrast other taxa within Crotalinae and Viperidae. The chosen reference specimen was compared to the presumed younger specimens to note any variation in ontogeny. The study here provides a comprehensive description of isolated cranial elements as well as a description of ontogenetic change within the specimens observed. This study contributes to the knowledge of osteological characters in T. wagleri and provides a foundation for a long term project to identify isolated elements in the fossil record.
    Matched MeSH terms: Fossils
  13. Mohammed Saifuddin, Amru N. Boyce
    Sains Malaysiana, 2017;46:1771-1778.
    As fossil energy resources are depleting quick and energy security is playing a vital role in the world economy. Quest for alternative energy sources have turned researches investigation in waste foods for next generation fuel. Biodiesel is usually considered to be environmentally friendly as it reduces greenhouse gas emission. Fish wastes rich in fatty acids and can be used as the raw material to produce biodiesel through transesterification reaction. The results showed that the seven peaks are fatty acid methyl esters, indicating all the triglycerides were successfully methylated to methyl esters. Fish based biodiesel provided a significant reduction in carbon monoxide (CO) and hydrocarbon (HC) emissions under engine loads of 15 (Nm) and required no engine modification. The viscosity of the produced biodiesel was within the range of international standards (ASTM). The biodiesel was found to contain a low base number and exhibited a lower specific fuel consumption compared to the conventional diesel. It can be concluded that biodiesel derived from waste fish oil can be considered as a potential source of commercial biodiesel.
    Matched MeSH terms: Fossils
  14. Zal U’yun Wan Mahmood, Mei, Wo Yii, Abdul Kadir Ishak
    MyJurnal
    This study was performed to observe the variation in the distribution of 210Po,210Pb and 210Po/210Pb activity ratio throughtheir vertical profile of the sediment cores takenat surrounding Sungai Linggi estuary. Five sediment cores were takenin February 2011 and were cutto an intervalof 2 cm layer. Activity concentrations of 210Po and 210Pb were determined using alpha radiochemical analysis and gamma direct measurement, respectively. Generally, the measured activity of 210Po, 210Pb and 210Po/210Pbwere in the ranges of 22.73 –139.06 Bqkg-1dw., 37.88 –176.24 Bqkg-1dw.and 0.23 –1.34, respectively. The variation in the distribution profile for the radionuclides are believed to be influencedby human activities such as agriculture, fertilizer, vehicles, burned fuel fossil and forest, industrialand others via river input from land-base.Other factor is due to organic mattercontent played importantrole as the geochemical carrier to transportthose radionuclides at study area. It was provedthat hasa strong correlation between the radionuclide distribution and the sedimentcomposition of organic matter.Furthermore, in those rangesreflectedthat 210Pb activities were higher than210Po with an activity ratio average of 0.79. This is probably due to dramatic increase of excess 210Pb supplied from atmospheric deposition, in situ decay of 226Ra and as a result of diagenetic remolibilazationof 210Pbin deeper layesof the sediment column. Thus, thosefactors are majorcontributions on thevariation of 210Po and 210Pb in the sediment core at surrounding Sungai Linggi estuary.
    Matched MeSH terms: Fossils
  15. Balasbaneh AT, Yeoh D, Juki MI, Ibrahim MHW, Abidin ARZ
    PMID: 33712956 DOI: 10.1007/s11356-021-13190-4
    This research aims to assess the sustainability of the most common earth-retaining walls (Gravity Walls and Cantilever Walls) in terms of environmental impacts, economic issues, and their combination. Gravity walls observed in this study consist of Gabion Wall, Crib Wall, and Rubble Masonry Wall, while Cantilever Walls include Reinforced Concrete Wall. Six different criteria were taken into account, including global warming potential, fossil depletion potential, eutrophication potential, acidification potential, human toxicity potential, and cost. To achieve the aim of this study, life cycle assessments, life cycle costs, and multi-criteria decision-making methods were implemented. The results showed that the most environmental-friendly option among all alternatives was the Gabion Wall, followed by the Rubble Masonry Wall. However, in terms of economic aspects, the Cantilever Concrete Wall was the best option, costing about 17% less than the Gabion Wall. On the other hand, the results of multi-criteria decision-making showed that the Gabion Wall was the most sustainable choice. This study addressed the research gap by carrying out a sustainability assessment of different retaining walls while considering cost and environmental impacts at the same time.
    Matched MeSH terms: Fossils
  16. Demarchi B, Stiller J, Grealy A, Mackie M, Deng Y, Gilbert T, et al.
    Proc Natl Acad Sci U S A, 2022 Oct 25;119(43):e2109326119.
    PMID: 35609205 DOI: 10.1073/pnas.2109326119
    The realization that ancient biomolecules are preserved in "fossil" samples has revolutionized archaeological science. Protein sequences survive longer than DNA, but their phylogenetic resolution is inferior; therefore, careful assessment of the research questions is required. Here, we show the potential of ancient proteins preserved in Pleistocene eggshell in addressing a longstanding controversy in human and animal evolution: the identity of the extinct bird that laid large eggs which were exploited by Australia's indigenous people. The eggs had been originally attributed to the iconic extinct flightless bird Genyornis newtoni (†Dromornithidae, Galloanseres) and were subsequently dated to before 50 ± 5 ka by Miller et al. [Nat. Commun. 7, 10496 (2016)]. This was taken to represent the likely extinction date for this endemic megafaunal species and thus implied a role of humans in its demise. A contrasting hypothesis, according to which the eggs were laid by a large mound-builder megapode (Megapodiidae, Galliformes), would therefore acquit humans of their responsibility in the extinction of Genyornis. Ancient protein sequences were reconstructed and used to assess the evolutionary proximity of the undetermined eggshell to extant birds, rejecting the megapode hypothesis. Authentic ancient DNA could not be confirmed from these highly degraded samples, but morphometric data also support the attribution of the eggshell to Genyornis. When used in triangulation to address well-defined hypotheses, paleoproteomics is a powerful tool for reconstructing the evolutionary history in ancient samples. In addition to the clarification of phylogenetic placement, these data provide a more nuanced understanding of the modes of interactions between humans and their environment.
    Matched MeSH terms: Fossils
  17. Matsumura H, Hudson MJ
    Am. J. Phys. Anthropol., 2005 Jun;127(2):182-209.
    PMID: 15558609
    This article uses metric and nonmetric dental data to test the "two-layer" or immigration hypothesis whereby Southeast Asia was initially occupied by an "Australo-Melanesian" population that later underwent substantial genetic admixture with East Asian immigrants associated with the spread of agriculture from the Neolithic period onwards. We examined teeth from 4,002 individuals comprising 42 prehistoric and historic samples from East Asia, Southeast Asia, Australia, and Melanesia. For the odontometric analysis, dental size proportions were compared using factor analysis and Q-mode correlation coefficients, and overall tooth size was also compared between population samples. Nonmetric population affinities were estimated by Smith's distances, using the frequencies of 16 tooth traits. The results of both the metric and nonmetric analyses demonstrate close affinities between recent Australo-Melanesian samples and samples representing early Southeast Asia, such as the Early to Middle Holocene series from Vietnam, Malaysia, and Flores. In contrast, the dental characteristics of most modern Southeast Asians exhibit a mixture of traits associated with East Asians and Australo-Melanesians, suggesting that these populations were genetically influenced by immigrants from East Asia. East Asian metric and/or nonmetric traits are also found in some prehistoric samples from Southeast Asia such as Ban Kao (Thailand), implying that immigration probably began in the early Neolithic. Much clearer influence of East Asian immigration was found in Early Metal Age Vietnamese and Sulawesi samples. Although the results of this study are consistent with the immigration hypothesis, analysis of additional Neolithic samples is needed to determine the exact timing of population dispersals into Southeast Asia.
    Matched MeSH terms: Fossils*
  18. Barnett R, Westbury MV, Sandoval-Velasco M, Vieira FG, Jeon S, Zazula G, et al.
    Curr Biol, 2020 Dec 21;30(24):5018-5025.e5.
    PMID: 33065008 DOI: 10.1016/j.cub.2020.09.051
    Homotherium was a genus of large-bodied scimitar-toothed cats, morphologically distinct from any extant felid species, that went extinct at the end of the Pleistocene [1-4]. They possessed large, saber-form serrated canine teeth, powerful forelimbs, a sloping back, and an enlarged optic bulb, all of which were key characteristics for predation on Pleistocene megafauna [5]. Previous mitochondrial DNA phylogenies suggested that it was a highly divergent sister lineage to all extant cat species [6-8]. However, mitochondrial phylogenies can be misled by hybridization [9], incomplete lineage sorting (ILS), or sex-biased dispersal patterns [10], which might be especially relevant for Homotherium since widespread mito-nuclear discrepancies have been uncovered in modern cats [10]. To examine the evolutionary history of Homotherium, we generated a ∼7x nuclear genome and a ∼38x exome from H. latidens using shotgun and target-capture sequencing approaches. Phylogenetic analyses reveal Homotherium as highly divergent (∼22.5 Ma) from living cat species, with no detectable signs of gene flow. Comparative genomic analyses found signatures of positive selection in several genes, including those involved in vision, cognitive function, and energy consumption, putatively consistent with diurnal activity, well-developed social behavior, and cursorial hunting [5]. Finally, we uncover relatively high levels of genetic diversity, suggesting that Homotherium may have been more abundant than the limited fossil record suggests [3, 4, 11-14]. Our findings complement and extend previous inferences from both the fossil record and initial molecular studies, enhancing our understanding of the evolution and ecology of this remarkable lineage.
    Matched MeSH terms: Fossils/anatomy & histology
  19. Barker G, Barton H, Bird M, Daly P, Datan I, Dykes A, et al.
    J Hum Evol, 2007 Mar;52(3):243-61.
    PMID: 17161859
    Recent research in Europe, Africa, and Southeast Asia suggests that we can no longer assume a direct and exclusive link between anatomically modern humans and behavioral modernity (the 'human revolution'), and assume that the presence of either one implies the presence of the other: discussions of the emergence of cultural complexity have to proceed with greater scrutiny of the evidence on a site-by-site basis to establish secure associations between the archaeology present there and the hominins who created it. This paper presents one such case study: Niah Cave in Sarawak on the island of Borneo, famous for the discovery in 1958 in the West Mouth of the Great Cave of a modern human skull, the 'Deep Skull,' controversially associated with radiocarbon dates of ca. 40,000 years before the present. A new chronostratigraphy has been developed through a re-investigation of the lithostratigraphy left by the earlier excavations, AMS-dating using three different comparative pre-treatments including ABOX of charcoal, and U-series using the Diffusion-Absorption model applied to fragments of bones from the Deep Skull itself. Stratigraphic reasons for earlier uncertainties about the antiquity of the skull are examined, and it is shown not to be an 'intrusive' artifact. It was probably excavated from fluvial-pond-desiccation deposits that accumulated episodically in a shallow basin immediately behind the cave entrance lip, in a climate that ranged from times of comparative aridity with complete desiccation, to episodes of greater surface wetness, changes attributed to regional climatic fluctuations. Vegetation outside the cave varied significantly over time, including wet lowland forest, montane forest, savannah, and grassland. The new dates and the lithostratigraphy relate the Deep Skull to evidence of episodes of human activity that range in date from ca. 46,000 to ca. 34,000 years ago. Initial investigations of sediment scorching, pollen, palynomorphs, phytoliths, plant macrofossils, and starch grains recovered from existing exposures, and of vertebrates from the current and the earlier excavations, suggest that human foraging during these times was marked by habitat-tailored hunting technologies, the collection and processing of toxic plants for consumption, and, perhaps, the use of fire at some forest-edges. The Niah evidence demonstrates the sophisticated nature of the subsistence behavior developed by modern humans to exploit the tropical environments that they encountered in Southeast Asia, including rainforest.
    Matched MeSH terms: Fossils*
  20. Rose JP, Kleist TJ, Löfstrand SD, Drew BT, Schönenberger J, Sytsma KJ
    Mol Phylogenet Evol, 2018 05;122:59-79.
    PMID: 29410353 DOI: 10.1016/j.ympev.2018.01.014
    Inferring interfamilial relationships within the eudicot order Ericales has remained one of the more recalcitrant problems in angiosperm phylogenetics, likely due to a rapid, ancient radiation. As a result, no comprehensive time-calibrated tree or biogeographical analysis of the order has been published. Here, we elucidate phylogenetic relationships within the order and then conduct time-dependent biogeographical and diversification analyses by using a taxon and locus-rich supermatrix approach on one-third of the extant species diversity calibrated with 23 macrofossils and two secondary calibration points. Our results corroborate previous studies and also suggest several new but poorly supported relationships. Newly suggested relationships are: (1) holoparasitic Mitrastemonaceae is sister to Lecythidaceae, (2) the clade formed by Mitrastemonaceae + Lecythidaceae is sister to Ericales excluding balsaminoids, (3) Theaceae is sister to the styracoids + sarracenioids + ericoids, and (4) subfamilial relationships with Ericaceae suggest that Arbutoideae is sister to Monotropoideae and Pyroloideae is sister to all subfamilies excluding Arbutoideae, Enkianthoideae, and Monotropoideae. Our results indicate Ericales began to diversify 110 Mya, within Indo-Malaysia and the Neotropics, with exchange between the two areas and expansion out of Indo-Malaysia becoming an important area in shaping the extant diversity of many families. Rapid cladogenesis occurred along the backbone of the order between 104 and 106 Mya. Jump dispersal is important within the order in the last 30 My, but vicariance is the most important cladogenetic driver of disjunctions at deeper levels of the phylogeny. We detect between 69 and 81 shifts in speciation rate throughout the order, the vast majority of which occurred within the last 30 My. We propose that range shifting may be responsible for older shifts in speciation rate, but more recent shifts may be better explained by morphological innovation.
    Matched MeSH terms: Fossils/history
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