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DNA traces in the Shroud of Turin reveal a remarkable mixture of human lineages, microbes, plants, animals, and coral accumulated through centuries of handling and travel。 The findings do not prove its age or authenticity, but they expose a hidden biological history preserved in the famous cloth
Mitochondrial DNA (mtDNA) has been used to study molecular ecology and phylogeography for 25 years. Much important information has been gained in this way, but it is time to reflect on the biology of the mitochondrion itself and consider opportunities for evolutionary studies of the organelle itself and its ecology, biochemistry and physiology. This review has four sections. First, we review aspects of the natural history of mitochondria and their DNA to show that it is a unique molecule with specific characteristics that differ from nuclear DNA. We do not attempt to cover the plethora of differences between mitochondrial and nuclear DNA; rather we spotlight differences that can cause significant bias when inferring demographic properties of populations and/or the evolutionary history of species. We focus on recombination, effective population size and mutation rate. Second, we explore some of the difficulties in interpreting phylogeographical data from mtDNA data alone and suggest a broader use of multiple nuclear markers. We argue that mtDNA is not a sufficient marker for phylogeographical studies if the focus of the investigation is the species and not the organelle. We focus on the potential bias caused by introgression. Third, we show that it is not safe to assume a priori that mtDNA evolves as a strictly neutral marker because both direct and indirect selection influence mitochondria. We outline some of the statistical tests of neutrality that can, and should, be applied to mtDNA sequence data prior to making any global statements concerning the history of the organism. We conclude with a critical examination of the neglected biology of mitochondria and point out several surprising gaps in the state of our knowledge about this important organelle. Here we limelight mitochondrial ecology, sexually antagonistic selection, life-history evolution including ageing and disease, and the evolution of mitochondrial inheritance.
At the core of Professor North's investigation is the question of property rights, the arrangements individuals and groups have made through history to deal with the fundamental economic problem of scarce resources. In six theoretical chapters, Professor North examines the structure of economic systems, outlines an economic theory of the state and the ideologies that undergird various modes of economic organization, and then explores the dynamic forces such as new technologies that cause institutions to adapt in order to survive. With this analytical framework in place, major phases in Western history come under careful reappraisal, from the origins of agriculture and the neolithic revolution through the political economy of the ancient and medieval worlds to the industrial revolution and the economic transformations of the twentieth century. Structure and Change in Economic History is a work that will reshape many established explanations of the growth of the west.
Fukuyama considers whether or not there is a direction to the history of mankind. He identifies two powerful forces guiding our actions: the logic of desire (the rational economic process); and the desire for recognition, which he describes as the very motor of history.
Research Article| April 01 1989 Between Memory and History: Les Lieux de Mémoire Pierre Nora Pierre Nora Search for other works by this author on: This Site PubMed Google Scholar Representations (1989) 26: 7–24. https://doi.org/10.2307/2928520 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Pierre Nora; Between Memory and History: Les Lieux de Mémoire. Representations 1 April 1989; 26 7–24. doi: https://doi.org/10.2307/2928520 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentRepresentations Search This content is only available via PDF. Copyright 1989 The Regents of the University of California Article PDF first page preview Close Modal You do not currently have access to this content.
Preface I. History and Conceptual Background 1. The History and Purview of Phylogeography 2. Demography-Phylogeny Connections II. Empirical Intraspecific Phylogeography 3. Lessons from Human Analyses 4. Intraspecific Patterns in other Animals III. Genealogical Concordance: Toward Speciation and Beyond 5. Genealogical Concordance 6. Speciation Processes and Extended Genealogy Works Cited Index
Scientists have demonstrated that heat can move through a crystal in focused, wave-like rays at room temperature instead of spreading randomly。 The breakthrough could make it possible to route heat around sensitive parts of next-generation chips and quantum devices
A ten-month Antarctic experiment found that astronauts may struggle not only with loneliness but also with spending too much time around the same people。 Frequent contact was linked to greater tension and mistrust, while the crew increasingly divided into cultural and language-based groups
Scientists have discovered incredibly tiny plasma whirlpools swirling across the Sun’s surface, some just 20 kilometers wide。 These previously invisible vortices may twist magnetic fields and help build up the energy released in small solar eruptions called nanoflares。 They may also help magnetic fields spread through the Sun’s atmosphere far faste
A massive magma reservoir has been detected deep beneath Tuscany, despite showing no obvious signs at the surface。 Scientists mapped the roughly 6,000-cubic-kilometer body using natural ground vibrations recorded by dozens of seismic sensors。 It poses no immediate danger, but the discovery reveals how enormous volcanic systems can remain hidden and
A black hole observed during a dramatic 2023 eruption did not simply devour gas from its nearby companion star。 It also expelled large amounts of material through powerful jets and winds, even after the outburst had nearly faded。 The results suggest black holes may continue reshaping their surroundings long after their brightest fireworks end
A new nanostructured carbon design lets fuel-cell catalysts use tiny amounts of platinum while remaining remarkably stable and efficient。 The breakthrough could help hydrogen fuel cells become a more practical way to power data centers, vehicles, and other energy-intensive technologies
A rare meteorite that crashed through a New Jersey roof contains evidence of ancient salty fluids, organic compounds, and amino acids from a primitive asteroid。 Its pristine chemistry could offer new clues about how space rocks helped supply early Earth with some of the ingredients needed for life
A mathematician working at Anthropic says he used the AI model Claude Fable 5 to uncover a remarkably simple counterexample to the Jacobian conjecture, a famous problem that has resisted mathematicians for more than a century。 The result shows that the conjecture is false in three dimensions and above, although the original two-dimensional version
Scientists have successfully generated electricity with a hydrogen turbine that produces its own pressure through detonation waves instead of relying on a mechanical compressor。 The breakthrough could unlock dramatically more efficient power systems for clean energy and future aviation
Dark matter particles may exert a hidden force on one another, but its effects are stranger than expected。 An extra attraction helps the particles cluster, yet it also makes dark matter effectively lighter as the Universe expands。 That weakens its gravitational impact and usually slows the growth of cosmic structure rather than accelerating it
Researchers have found a way to build much larger “twisted” oxide materials while precisely controlling how their atomic layers line up。 Because these materials can be made over large areas and transferred onto different surfaces, the technique could help turn twistronics from a laboratory curiosity into a practical platform for next-generation ele
A surprisingly simple change could make sodium-ion batteries far more powerful while opening the door to turning seawater into drinking water。 Researchers at the University of Surrey found that sodium vanadium oxide performs much better when its naturally occurring water is left inside instead of being removed during manufacturing