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A reduced HOMO−LUMO gap, which is defined as the HOMO−LUMO energy separation of a molecule divided by that of the hypothetical polyene reference, can be used as an index of kinetic stability for a variety of polycyclic aromatic hydrocarbons (PAHs). The reduced HOMO−LUMO gap < 1.00 indicates that the HOMO contributes to the decrease in the topological resonance energy. In general, PAHs with reduced HOMO−LUMO gaps < 1.30 are chemically very reactive. Fully benzenoid hydrocarbons are kinetically very stable with very large reduced HOMO−LUMO gaps. Many of the PAH molecules with large reduced HOMO−LUMO gaps are closed-shell substructures of nonmetallic one-dimensional benzenoid polymers.

A complex of traits in the femur and pelvis of Homo erectus and early "erectus-like" specimens has been described, but never satisfactorily explained. Here the functional relationships between pelvic and femoral structure in humans are explored using both theoretical biomechanical models and empirical tests within modern samples of diverse body form (Pecos Amerindians, East Africans). Results indicate that a long femoral neck increases mediolateral bending of the femoral diaphysis and decreases gluteal abductor and hip joint reaction forces. Increasing biacetabular breadth along with femoral neck length further increases M-L bending of the femoral shaft and maintains abductor and joint reaction forces at near "normal" levels. When compared to modern humans, Homo erectus and early "erectus-like" specimens are characterized by a long femoral neck and greatly increased M-L relative to A-P bending strength of the femoral shaft, coupled with no decrease in hip joint size and a probable increase in abductor force relative to body size. All of this strongly suggests that biacetabular breadth as well as femoral neck length was relatively large in early Homo. Several features preserved in early Homo partial hip bones also indicate that the true (lower) pelvis was very M-L broad, as well as A-P narrow. This is similar to the lower pelvic shape of australopithecines and suggests that nonrotational birth, in which the newborn's head is oriented transversely through the pelvic outlet, characterized early Homo as well as Australopithecus. Because M-L breadth of the pelvis is constrained by other factors, this may have limited increases in cranial capacity within Homo until rotational birth was established during the late Middle Pleistocene. During or after the transition to rotational birth biacetabular breadth decreased, reducing the body weight moment arm about the hip and allowing femoral neck length (abductor moment arm) to also decrease, both of which reduced M-L bending of the proximal femoral shaft. Variation in femoral structural properties within early Homo and other East African Early Pleistocene specimens has several taxonomic and phylogenetic implications.

Homo naledi is a previously-unknown species of extinct hominin discovered within the Dinaledi Chamber of the Rising Star cave system, Cradle of Humankind, South Africa. This species is characterized by body mass and stature similar to small-bodied human populations but a small endocranial volume similar to australopiths. Cranial morphology of H. naledi is unique, but most similar to early Homo species including Homo erectus, Homo habilis or Homo rudolfensis. While primitive, the dentition is generally small and simple in occlusal morphology. H. naledi has humanlike manipulatory adaptations of the hand and wrist. It also exhibits a humanlike foot and lower limb. These humanlike aspects are contrasted in the postcrania with a more primitive or australopith-like trunk, shoulder, pelvis and proximal femur. Representing at least 15 individuals with most skeletal elements repeated multiple times, this is the largest assemblage of a single species of hominins yet discovered in Africa.

The first discoveries of Homo erectus were made in Java late in the 19th century. Since then many fossils have come to light in Africa as well as Asia. Homo erectus seems to have evolved in Africa before spreading to other regions of the Old World. This occurred over a long period of time, during which the populations changed relatively little. Only towards the close of the middle Pleistocene are there signs of change in evolutionary tempo leading to the appearance of more advanced humans. This book provides a wealth of information about individual crania, jaws and postcranial remains and will serve as an important guide to the anatomy of Homo erectus. It also documents the history of this extinct human species and suggests a route whereby Homo erectus may have given rise to people more like Homo sapiens.

Louis Dumont's modern classic, here presented in an enlarged, revised, and corrected second edition, simultaneously supplies that reader with the most cogent statement on the Indian caste system and its organizing principles and a provocative advance in the comparison of societies on the basis of their underlying ideologies. Dumont moves gracefully from the ethnographic data to the level of the hierarchical ideology encrusted in ancient religious texts which are revealed as the governing conception of the contemporary caste structure. On yet another plane of analysis, homo hierarchicus is contrasted with his modern Western antithesis, homo aequalis. This edition includes a lengthy new Preface in which Dumont reviews the academic discussion inspired by Homo Hierarchicus and answers his critics. A new Postface, which sketches the theoretical and comparative aspects of the concept of hierarchy, and three significant Appendixes previously omitted from the English translation complete this innovative and influential work.

Introduction Part I. The Logic of Sovereignty: 1. The paradox of sovereignty 2. 'Nomos Basileus' 3. Potentiality and law 4. Form of law Threshold Part II. Homo Sacer: 1. Homo sacer 2. The ambivalence of the sacred 3. Sacred life 4. 'Vitae Necisque Potestas' 5. Sovereign body and sacred body 6. The ban and the wolf Threshold Part III. The Camp as Biopolitical Paradigm of the Modern: 1. The politicization of life 2. Biopolitics and the rights of man 3. Life that does not deserve to live 4. 'Politics, or giving form to the life of a people' 5. VP 6. Politicizing death 7. The camp as the 'Nomos' of the modern Threshold Bibliography Index of names.

In seinem Kultbuch „Eine kurze Geschichte der Menschheit“ erklärte Yuval Noah Harari, wie unsere Spezies die Erde erobern konnte. In „Homo Deus“ stößt er vor in eine noch verborgene Welt: die Zukunft. Was wird mit uns und unserem Planeten passieren, wenn die neuen Technologien dem Menschen gottgleiche Fähigkeiten verleihen – schöpferische wie zerstörerische – und das Leben selbst auf eine völlig neue Stufe der Evolution heben? Wie wird es dem Homo Sapiens ergehen, wenn er einen technikverstärkten Homo Deus erschafft, der sich vom heutigen Menschen deutlicher unterscheidet als dieser vom Neandertaler? Was bleibt von uns und der modernen Religion des Humanismus, wenn wir Maschinen konstruieren, die alles besser können als wir? In unserer Gier nach Gesundheit, Glück und Macht könnten wir uns ganz allmählich so weit verändern, bis wir schließlich keine Menschen mehr sind.

Cellular processes often depend on interactions between proteins and the formation of macromolecular complexes. The impairment of such interactions can lead to deregulation of pathways resulting in disease states, and it is hence crucial to gain insights into the nature of macromolecular assemblies. Detailed structural knowledge about complexes and protein-protein interactions is growing, but experimentally determined three-dimensional multimeric assemblies are outnumbered by complexes supported by non-structural experimental evidence. Here, we aim to fill this gap by modeling multimeric structures by homology, only using amino acid sequences to infer the stoichiometry and the overall structure of the assembly. We ask which properties of proteins within a family can assist in the prediction of correct quaternary structure. Specifically, we introduce a description of protein-protein interface conservation as a function of evolutionary distance to reduce the noise in deep multiple sequence alignments. We also define a distance measure to structurally compare homologous multimeric protein complexes. This allows us to hierarchically cluster protein structures and quantify the diversity of alternative biological assemblies known today. We find that a combination of conservation scores, structural clustering, and classical interface descriptors, can improve the selection of homologous protein templates leading to reliable models of protein complexes.

In responding to a request for predictions about the future of economics, I predict that Homo Economicus will evolve into Homo Sapiens, or, more simply put, economics will become more related to human behavior. My specific predictions are that Homo Economicus will start to lose IQ, will become a slower learner, will start interacting with other species, and that economists will start to study human cognition, human emotion, and will distinguish more clearly between normative and descriptive theories.

Integration of evidence over the past decade has revised understandings about the major adaptations underlying the origin and early evolution of the genus Homo. Many features associated with Homo sapiens, including our large linear bodies, elongated hind limbs, large energy-expensive brains, reduced sexual dimorphism, increased carnivory, and unique life history traits, were once thought to have evolved near the origin of the genus in response to heightened aridity and open habitats in Africa. However, recent analyses of fossil, archaeological, and environmental data indicate that such traits did not arise as a single package. Instead, some arose substantially earlier and some later than previously thought. From ~2.5 to 1.5 million years ago, three lineages of early Homo evolved in a context of habitat instability and fragmentation on seasonal, intergenerational, and evolutionary time scales. These contexts gave a selective advantage to traits, such as dietary flexibility and larger body size, that facilitated survival in shifting environments.

Ein grundlegendes Element unserer Kultur ist das Spiel. Der Mensch ist ein Spieler - und ohne seine Lust und Fähigkeit zum Spielen hätten sich ganze Bereiche seiner Kultur nicht entwickelt: die Dichtung, das Recht, die Wissenschaft, die bildende Kunst, die Philosophie und viele andere. Johan Huizinga, der grosse holländische Historiker und Kulturphilosoph, hat in diesem Buch eine Theorie der Kultur entworfen, in der er dem Denker (homo sapiens) und dem Tätigen (homo faber) den Menschen als Spieler (homo ludens) an die Seite stellt. Ein klassischer Essay der Kulturgeschichte und Anthropologie.

Yuval Noah Harari, author of the critically-acclaimed New York Times bestseller and international phenomenon Sapiens, returns with an equally original, compelling, and provocative book, turning his focus toward humanity’s future, and our quest to upgrade humans into gods. Over the past century humankind has managed to do the impossible and rein in famine, plague, and war. This may seem hard to accept, but, as Harari explains in his trademark style—thorough, yet riveting—famine, plague and war have been transformed from incomprehensible and uncontrollable forces of nature into manageable challenges. For the first time ever, more people die from eating too much than from eating too little; more people die from old age than from infectious diseases; and more people commit suicide than are killed by soldiers, terrorists and criminals put together. The average American is a thousand times more likely to die from binging at McDonalds than from being blown up by Al Qaeda. What then will replace famine, plague, and war at the top of the human agenda? As the self-made gods of planet earth, what destinies will we set ourselves, and which quests will we undertake? Homo Deus explores the projects, dreams and nightmares that will shape the twenty-first century—from overcoming death to creating artificial life. It asks the fundamental questions: Where do we go from here? And how will we protect this fragile world from our own destructive powers? This is the next stage of evolution. This is Homo Deus. With the same insight and clarity that made Sapiens

Despite a rich African Plio-Pleistocene hominin fossil record, the ancestry of Homo and its relation to earlier australopithecines remain unresolved. Here we report on two partial skeletons with an age of 1.95 to 1.78 million years. The fossils were encased in cave deposits at the Malapa site in South Africa. The skeletons were found close together and are directly associated with craniodental remains. Together they represent a new species of Australopithecus that is probably descended from Australopithecus africanus. Combined craniodental and postcranial evidence demonstrates that this new species shares more derived features with early Homo than any other australopith species and thus might help reveal the ancestor of that genus.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLate-Metal Catalysts for Ethylene Homo- and CopolymerizationSteven D. Ittel, Lynda K. Johnson, and Maurice BrookhartView Author Information DuPont Central Research & Development, Wilmington, Delaware 19880-0328 Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290 Cite this: Chem. Rev. 2000, 100, 4, 1169–1204Publication Date (Web):March 25, 2000Publication History Received13 September 1999Published online25 March 2000Published inissue 1 April 2000https://pubs.acs.org/doi/10.1021/cr9804644https://doi.org/10.1021/cr9804644research-articleACS PublicationsCopyright © 2000 American Chemical SocietyRequest reuse permissionsArticle Views17048Altmetric-Citations2823LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Alkyls,Catalysts,Hydrocarbons,Ligands,Nickel Get e-Alerts

In Search of Homo Economicus: Behavioral Experiments in 15 Small-Scale Societies by Joseph Henrich, Robert Boyd, Samuel Bowles, Colin Camerer, Ernst Fehr, Herbert Gintis and Richard McElreath. Published in volume 91, issue 2, pages 73-78 of American Economic Review, May 2001

If we restrict the use of Homo sapiens in the fossil record to specimens which share a significant number of derived features in the skeleton with extant H. sapiens, the origin of our species would be placed in the African late middle Pleistocene, based on fossils such as Omo Kibish 1, Herto 1 and 2, and the Levantine material from Skhul and Qafzeh. However, genetic data suggest that we and our sister species Homo neanderthalensis shared a last common ancestor in the middle Pleistocene approximately 400-700 ka, which is at least 200 000 years earlier than the species origin indicated from the fossils already mentioned. Thus, it is likely that the African fossil record will document early members of the sapiens lineage showing only some of the derived features of late members of the lineage. On that basis, I argue that human fossils such as those from Jebel Irhoud, Florisbad, Eliye Springs and Omo Kibish 2 do represent early members of the species, but variation across the African later middle Pleistocene/early Middle Stone Age fossils shows that there was not a simple linear progression towards later sapiens morphology, and there was chronological overlap between different 'archaic' and 'modern' morphs. Even in the late Pleistocene within and outside Africa, we find H. sapiens specimens which are clearly outside the range of Holocene members of the species, showing the complexity of recent human evolution. The impact on species recognition of late Pleistocene gene flow between the lineages of modern humans, Neanderthals and Denisovans is also discussed, and finally, I reconsider the nature of the middle Pleistocene ancestor of these lineages, based on recent morphological and genetic data.This article is part of the themed issue 'Major transitions in human evolution'.

Heuristics are efficient cognitive processes that ignore information. In contrast to the widely held view that less processing reduces accuracy, the study of heuristics shows that less information, computation, and time can in fact improve accuracy. We review the major progress made so far: (a) the discovery of less-is-more effects; (b) the study of the ecological rationality of heuristics, which examines in which environments a given strategy succeeds or fails, and why; (c) an advancement from vague labels to computational models of heuristics; (d) the development of a systematic theory of heuristics that identifies their building blocks and the evolved capacities they exploit, and views the cognitive system as relying on an "adaptive toolbox;" and (e) the development of an empirical methodology that accounts for individual differences, conducts competitive tests, and has provided evidence for people's adaptive use of heuristics. Homo heuristicus has a biased mind and ignores part of the available information, yet a biased mind can handle uncertainty more efficiently and robustly than an unbiased mind relying on more resource-intensive and general-purpose processing strategies.

One of Italy's most original philosophers aims to connect the problem of pure possibility, potentiality, and power with the problem of political and social ethics in a context where the latter has lost its previous religious, metaphysical, and cultural grounding.

The sociology of culture seeks to locate the world of the arts within the broader context of the institutions and ideology of society. This wide-ranging set covers the sociology of dance, literary taste and cinema. Taking into account also the cultural context of play and child-rearing, this is important reading for students and researchers in Cultural Studies.