Neandertal and Denisovan DNA from Pleistocene sediments Slon, Viviane; Hopfe, Charlotte; Weiß, Clemens L. ...
Science (American Association for the Advancement of Science),
05/2017, Letnik:
356, Številka:
6338
Journal Article, Web Resource
Recenzirano
Odprti dostop
Although a rich record of Pleistocene human-associated archaeological assemblages exists, the scarcity of hominin fossils often impedes the understanding of which hominins occupied a site. Using ...targeted enrichment of mitochondrial DNA, we show that cave sediments represent a rich source of ancient mammalian DNA that often includes traces of hominin DNA, even at sites and in layers where no hominin remains have been discovered. By automation-assisted screening of numerous sediment samples, we detected Neandertal DNA in eight archaeological layers from four caves in Eurasia. In Denisova Cave, we retrieved Denisovan DNA in a Middle Pleistocene layer near the bottom of the stratigraphy. Our work opens the possibility of detecting the presence of hominin groups at sites and in areas where no skeletal remains are found.
Herein we describe Ocrepeira klamt sp. n. (Araneae: Araneidae), a new orb-weaving spider species from a Colombian páramo, which was formerly inaccessible for scientific studies due to decades long ...armed conflicts. Both, phenotypic and molecular data are used to confirm genus affiliation, and the new species is placed into phylogenetic context with other araneid spiders. Morphological characteristics and ecological notes of Ocrepeira klamt sp. n. are reported together with the sequence of the barcoding region of cytochrome c oxidase subunit I (COI) to provide a comprehensive description of the spider, facilitating future identification beyond taxonomic experts. With this study we contribute to the taxonomic knowledge that is required to inventory the hyper diverse yet threatened ecosystem of the Colombian páramos.
The anthropogenic modification of trophic pathways is seemingly prompting the increase of jellyfish populations at the expense of planktivorous fishes. However, gross generalizations are often made ...because the most basic aspects of trophic ecology and the diverse interactions of jellyfish with fishes remain poorly described. Here we inquire on the dynamics of food consumption of the medusoid stage of the scyphozoan jellyfish
and characterize the traits and diversity of its symbiotic community.
and their associated fauna were sampled in surface waters between November 2015 and April 2017 in Málaga Bay, an estuarine system at the Colombian Pacific. Stomach contents of medusae were examined and changes in prey composition and abundance over time analysed using a multivariate approach. The associated fauna was identified and the relationship between the size of medusae and the size those organisms tested using least-square fitting procedures.
The presence of
medusa in surface waters was seasonal. The gut contents analysis revealed that algae, copepods and fish early life stages were the more abundant items, and PERMANOVA analysis showed that the diet differed within the seasons (
= 0.001) but not between seasons (
= 0.134). The majority of the collected medusae (50.4%) were associated with individuals of 11 symbiotic species, 95.3% of them fishes, 3.1% crustaceans and 1.6% molluscs. Therefore, this study reports 10 previously unknown associations. The bell diameter of
was positively related to the body sizes of their symbionts. However, a stronger fit was observed when the size relationship between
and the fish
was modelled.
The occurrence of
was highly seasonal, and the observed patterns of mean body size through the seasons suggested the arrival of adult medusae to the estuary from adjacent waters. The diet of
in the study area showed differences with previous reports, chiefly because of the abundance of algae that are seemingly ingested but not digested. The low number of zooplanktonic items in gut contents suggest the contribution of alternative food sources not easily identifiable. The observed changes in the composition of food in the guts probably reflect seasonal changes in the availability of prey items. The regular pattern in the distribution of symbionts among medusae (a single symbiont per host) and the positive host-symbiont size relationship reflects antagonistic intraspecific and interspecific behaviour of the symbiont. This strongly suggest that medusa represent an "economically defendable resource" that potentially increases the survival and recruitment of the symbionts to the adult population. We argue that, if this outcome of the symbiotic association can be proven, scyphozoan jellyfish can be regarded as floating nurseries.
To date, the only Neandertal genome that has been sequenced to high quality is from an individual found in Southern Siberia. We sequenced the genome of a female Neandertal from ~50,000 years ago from ...Vindija Cave, Croatia, to ~30-fold genomic coverage. She carried 1.6 differences per 10,000 base pairs between the two copies of her genome, fewer than present-day humans, suggesting that Neandertal populations were of small size. Our analyses indicate that she was more closely related to the Neandertals that mixed with the ancestors of present-day humans living outside of sub-Saharan Africa than the previously sequenced Neandertal from Siberia, allowing 10 to 20% more Neandertal DNA to be identified in present-day humans, including variants involved in low-density lipoprotein cholesterol concentrations, schizophrenia, and other diseases.
The energy transition requires policy makers to adopt a holistic view that also considers non-economic factors when developing cleaner technology deployment schemes. In particular, a broad knowledge ...base is required to ensure an efficient energetic use of the limited biomass potential. Energy system optimization models are widely used to inform decision makers about energy transition strategies. The heterogeneity of consumers, especially in the heat sector, is rarely considered in these models and therefore these models lack of completion to contribute to this holistic approach. In this study, a literature review was conducted to find empirical data on consumer behavior regarding the adoption of residential heating systems. This data was integrated into an optimization model for the German heat sector, combining established methods for integrating consumer heterogeneity with a novel approach for calculating indirect costs representing behavioral factors. The incorporation of consumer choice leads to a broader distribution of market shares of different technologies in both a “business-as-usual” scenario and an “ambitious measures” scenario. In particular, the future role of log wood technologies in the private household sector may have been underestimated in previous studies and should be discussed, when designing policies. With this study, the knowledge base for decision makers was extended to discuss the future efficient use of biomass within the German heat sector.
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Spider orb webs have evolved to stop flying prey, fast and slow alike. One of the main web elements dissipating impact energy is the radial fibers, or major ampullate silks, which possess a toughness ...surpassing most man-made materials. Orb webs are extended phenotypes, and as such their architectural elements, including major ampullate silks, have been selected to optimize prey capture under the respective environmental conditions. In this study, we investigated the correlation of three landscape scales and three microhabitat characteristics with intrinsic silk properties (elastic modulus, yield stress, tensile strength, extensibility, and toughness) to understand underlying ecological patterns. For this purpose, we collected and mechanically tested major ampullate silks from 50 spider species inhabiting large altitudinal and climatic gradients in Colombia. Using regression analysis and model selection, we investigated the environmental drivers of inter- and intra-specific patterns of major ampullate silk properties, taking into account phylogenetic relatedness based on newly sequenced mitochondrial genomes. We found that the total amount of energy absorbed, i.e., toughness and tensile strength, is higher for fibers from species inhabiting regions where heavy rainfall is common. Interestingly, we observe the same general trend between individuals of the same species, stressing the importance of this environmental driver. We also observe a phylogenetic conservation in the relation of environmental variables with silk tensile strength and yield stress. In conclusion, the increase in major ampullate silk tensile strength and toughness may reflect an adaptation to prevent frequent rain damage to orb webs and the associated energetic loss.
Proteinfasern als Hochleistungsmaterial Bargel, Hendrik; Hopfe, Charlotte; Scheibel, Thomas
Biologie in Unserer Zeit,
12/2020, Letnik:
50, Številka:
6
Journal Article
Recenzirano
Zusammenfassung
Der evolutionäre Erfolg von Spinnen (Araneae) ist eng mit der Entwicklung und vielfältigen Verwendung ihrer Spinnenseiden verknüpft. Das Fasermaterial wird z. B. zum Schutz der ...Nachkommen, zur Verbreitung und Orientierung, und für den Beutefang genutzt. Etwa die Hälfte der über 48.000 bekannten Arten baut Netze, deren Variabilität als Beispiel für eine Koevolution mit Insekten und deren Lebensräumen gilt. Im Laufe der Evolution entstanden durch Anpassungen an die Beuteökologie und Veränderungen der Spidroine auf molekularer Ebene Hochleistungsmaterialien wie die Seiden der Großen Ampullendrüse, deren Zähigkeit die vieler technischer Materialien überragt. Die Etablierung einer rekombinanten Produktion von designten Spidroinen im industriellen Maßstab hat die Nutzung biokompatibler, wundheilungsfördernder und bakteriostatischer Seiden als nachhaltige Biopolymere in vielfältigen Anwendungen in Kosmetik, Biomedizin, Spezialtextilien, Filtermaterialien und Nanobiotechnologie ermöglicht.
Summary
Evolution, properties and applications of spider silk
The evolutionary success of spiders (Araneae) is closely linked to the development and multiple purposes of their silks. The fibrous material is used to protect their offspring, for distribution and orientation, and especially for prey catching. About half of the approx. 48,000 known species build webs, the variability of which is considered an example of co‐evolution with insects and their habitats. In the course of evolution, adaptation to prey ecology and changes at the molecular level led to high‐performance materials such as the silks of the Major Ampullate gland (MA silk), with mechanical toughness surpassing that of most technical materials. The establishment of recombinant production on an industrial scale has enabled the use of biocompatible, wound‐healing and bacteriostatic silks as green sustainable biopolymers in a wide range of applications such as cosmetics, biomedicine, special textiles, filter materials, and nanobiotechnology.
Proteinfasern als Hochleistungsmaterial Bargel, Hendrik; Hopfe, Charlotte; Scheibel, Thomas
Biologie in Unserer Zeit,
December 2020, Letnik:
50, Številka:
6
Journal Article
Recenzirano
Zusammenfassung
Der evolutionäre Erfolg von Spinnen (Araneae) ist eng mit der Entwicklung und vielfältigen Verwendung ihrer Spinnenseiden verknüpft. Das Fasermaterial wird z. B. zum Schutz der ...Nachkommen, zur Verbreitung und Orientierung, und für den Beutefang genutzt. Etwa die Hälfte der über 48.000 bekannten Arten baut Netze, deren Variabilität als Beispiel für eine Koevolution mit Insekten und deren Lebensräumen gilt. Im Laufe der Evolution entstanden durch Anpassungen an die Beuteökologie und Veränderungen der Spidroine auf molekularer Ebene Hochleistungsmaterialien wie die Seiden der Großen Ampullendrüse, deren Zähigkeit die vieler technischer Materialien überragt. Die Etablierung einer rekombinanten Produktion von designten Spidroinen im industriellen Maßstab hat die Nutzung biokompatibler, wundheilungsfördernder und bakteriostatischer Seiden als nachhaltige Biopolymere in vielfältigen Anwendungen in Kosmetik, Biomedizin, Spezialtextilien, Filtermaterialien und Nanobiotechnologie ermöglicht.
Summary
Evolution, properties and applications of spider silk
The evolutionary success of spiders (Araneae) is closely linked to the development and multiple purposes of their silks. The fibrous material is used to protect their offspring, for distribution and orientation, and especially for prey catching. About half of the approx. 48,000 known species build webs, the variability of which is considered an example of co‐evolution with insects and their habitats. In the course of evolution, adaptation to prey ecology and changes at the molecular level led to high‐performance materials such as the silks of the Major Ampullate gland (MA silk), with mechanical toughness surpassing that of most technical materials. The establishment of recombinant production on an industrial scale has enabled the use of biocompatible, wound‐healing and bacteriostatic silks as green sustainable biopolymers in a wide range of applications such as cosmetics, biomedicine, special textiles, filter materials, and nanobiotechnology.
Webspinnen sind mit 48.000 beschriebenen Arten eine der größten Tiergruppen überhaupt. Ein Grund für diesen evolutionären Erfolg sind ihre außergewöhnlichen Netzkonstruktionen aus Seide. Spinnenseide hat beeindruckende Materialeigenschaften und kann in vielfältigen Anwendungen zum Einsatz kommen.
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