Computer simulations show that Neanderthal facial morphology represents adaptation to cold and high energy demands, but not heavy biting

Three adaptive hypotheses have been forwarded to explain the distinctive Neanderthal face: (i) an improved ability to accommodate high anterior bite forces, (ii) more effective conditioning of cold and/or dry air and, (iii) adaptation to facilitate greater ventilatory demands. We test these hypotheses using three-dimensional models of Neanderthals, modern humans, and a close outgroup (Homo heidelbergensis), applying finite-element analysis (FEA) and computational fluid dynamics (CFD). This is the most comprehensive application of either approach applied to date and the first to include both. FEA reveals few differences between H. heidelbergensis, modern humans, and Neanderthals in their capacities to sustain high anterior tooth loadings. CFD shows that the nasal cavities of Neanderthals and especially modern humans condition air more efficiently than does that of H. heidelbergensis, suggesting that both evolved to better withstand cold and/or dry climates than less derived Homo. We further find that Neanderthals could move considerably more air through the nasal pathway than could H. heidelbergensis or modern humans, consistent with the propositions that, relative to our outgroup Homo, Neanderthal facial morphology evolved to reflect improved capacities to better condition cold, dry air, and, to move greater air volumes in response to higher energetic requirements

Com la covariància evolutiva ens va fer respirar malament

S'ha suggerit que la morfologia i mida dels individus de les poblacions humanes presenta una correlació amb el clima i el gradient latitudinal. Seguint la regla d'Allen, per tal d'evitar la transferència de calor amb l'entorn, en latituds més equatorials els humans tendeixen a ser alts i esvelts, mentre que als pols és el contrari per tal de conservar la calor corporal. En relació amb aquesta idea, la morfologia de la cavitat nasal també seguiria aquesta teoria iestaria vinculada a la forma en la qual se condiciona l'aire per arribar al pulmó en condicions òptimes de temperatura i humitat. Els individus en climes freds o secs haurien de tenir una major superfície de la mucosa nasal en relació amb el volum d'aire de les fosses nasals que els individus en climes càlids i humits, ja que les superfícies més grans afavoreixen l'intercanvi de calor amb l'aire que entra, escalfant-lo. Es teoritza que, a mesura que les primeres poblacions d'Homo es van traslladar cap als climes més freds d'Euràsia, els nassos van evolucionar per escalfar l'aire inhalat, fent-se més prims i estrets. Malgrat això, estudis recents han trobat que la cavitat nasal en si mateixa pot no ser suficient per condicionar l'aire que entra als pulmons, pot ser la morfologia nasal podria no estar seleccionada amb el gradient ecològic sinó amb l'evolutiu. Si és així, com es fa l'aire condicionat a l'Homo de cara plana? I hi ha un motiu conegut per al canvi de forma del nas

The evolution, form and function of the human respiratory system

This paper presents an updated view on the morphological and functional significance of the human respiratory system in the context of human evolutionary anatomy. While usually the respiratory system is treated either from a craniofacial perspective, mostly in the context of nasal evolution and air-conditioning, or from a postcranial perspective featuring on overall thoracic shape changes, here we pursue a holistic perspective on the form, function, integration, and evolutionary change of the entire organismal system in hominins. We first present a brief review of the most important morphological structures, their function, and its potential integration and interaction with the nasal cavity and thoracic skeleton. This is followed by an overview of the most important improvements in methods for the comparative study in recent humans and fossil hominins. We then overview and list a compendium of hominin fossil material currently available for the study. We propose four functional categories of hominin respiratory system configurations that differ potentially with respect to size, shape, biomechanics and/or bioenergetics. Finally, we discuss these and speculate on possible ways for future research into an anatomical system that, despite its under-investigated status, is central to the understanding of the form and functions of the hominin organism and its paleobiology.Grant PID2020-115854GB-I00 to MB is funded by MCIN/AEI/10.13039/501100011033 of the Spanish Ministry of Science and Innovation and the European Union and is linked to PRE2021- 097584 FPI dissertation grant to JMLRP. Grants PID2019-105097RB I00/AEI/10.13039/501100011033) and PDC2022-133532-I00 are funded to MAB. MLC is funded by a FPU21/02087 Dissertation grant. Grant IIPPITD-2021 is funded to APR for stays of UMA researchers in quality research centers.Peer reviewe

Structure, function and context : the impact of morphometry and ecology on olfactory sensitivity

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February, 2005In this thesis, the relationships of olfactory sensitivity to three biological variables were tested. The sensitivity of a marine mammal, the sea otter (Enhydra lutris) was measured in order to determine whether a marine lifestyle results in impaired olfaction. The effect of dietary relevance on sensitivity to specific odorants was evaluated. Finally, a new morphometric model of olfactory uptake efficiency was developed and tested against behavioral measurements of olfactory sensitivity in twelve mammalian species from five orders. Olfactory thresholds were obtained for the first time from two sea otters for seven odorant compounds from various natural sources. Otters were trained using operant conditioning to participate in direct behavioral testing. Sea otter olfactory sensitivity was comparable to that of previously studied terrestrial mammals. The incidence of an odorant in the diet of the olfactor was found to influence specific sensitivity to that compound but to varying degrees among different mammalian orders. Nasal cavity specimens were measured using radiologic (CT scan) and histologic (light microscopy) techniques. Surface areas and volumes of the nasal cavity were used to calculate the Olfactory Uptake Efficiency (OUE). OUE is significantly related to olfactory bulb volume. A possible relationship was found between OUE and general olfactory sensitivity.I am grateful to the Oregon Zoo and the Oregon Coast Aquarium, whose exhibit animals provided the olfactory threshold data, as well as the Monterey Bay Aquarium, the Point Defiance Zoo and the New England Aquarium, which also participated. Nasal cavity specimens were generously donated by the American Museum of Natural History, the Whitehead Institute at the Massachusetts Institute of Technology, the Biology Department of MIT, the California Oiled Wildlife Network, the Harvard Museum of Comparative Zoology, the Institute for Hydrology and Ecology at Monk's Hood, Tufts Veterinary School, the New England Regional Primate Research Center, Lion Country Safari Zoo, and the Cameron Park Zoo. Funding was provided by the Woods Hole Oceanographic Institution's Education Department, Biology Department and Ocean Ventures Fund, the National Science and Engineering Research Council of Canada, the Gen Foundation, the Massachusetts Institute of Technology's Student Assistance Fund, the European Chemoreception Research Organization, the Society for Experimental Biology, the Company of Biologists, and the Office of Naval Research

Impact of morphometry and ecology on olfactory sensitivity

Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Biology; and, the Woods Hole Oceanographic Institution), 2005.Handwritten on CDROMS: v. [1]. Appendix, histological images -- v. [2]. CT images. -- Table of contents refers to CDROMS as: Appendix and CT and histological images for all species, attached CD)Includes bibliographical references (v. 2, leaves 216-247).In this thesis, the relationships of olfactory sensitivity to three biological variables were tested. The sensitivity of a marine mammal, the sea otter (Enhydra lutris) was measured in order to determine whether a marine lifestyle results in impaired olfaction. The effect of dietary relevance on sensitivity to specific odorants was evaluated. Finally, a new morphometric model of olfactory uptake efficiency was developed and tested against behavioral measurements of olfactory sensitivity in twelve mammalian species from five orders. Olfactory thresholds were obtained for the first time from two sea otters for seven odorant compounds from various natural sources. Otters were trained using operant conditioning to participate in direct behavioral testing. Sea otter olfactory sensitivity was comparable to that of previously studied terrestrial mammals. The incidence of an odorant in the diet of the olfactor was found to influence specific sensitivity to that compound but to varying degrees among different mammalian orders. Nasal cavity specimens were measured using radiologic (CT scan) and histologic (light microscopy) techniques. Surface areas and volumes of the nasal cavity were used to calculate the Olfactory Uptake Efficiency (OUE). OUE is significantly related to olfactory bulb volume. A possible relationship was found between OUE and general olfactory sensitivity.by Jennifer Hammock.Ph.D

Reconstructing Soft Tissues of Plio-Pleistocene Hominids using Comparative Anatomy of Modern Humans & Great Apes

The aim of facial approximation is to recreate the appearance of an individual from their dry skull. This technique has often been used following the discovery of a new species of ancient hominid, such as those belonging to the Australopithecus or Paranthropus genera. Facial approximations provide a 3D model for these species and provides another means for scientists to understand the morphological differences between and variations among archaic hominids and modern humans. These models, which are often produced three-dimensionally, also help to guide public attention towards biological anthropology and to disseminate scientific facts about human evolution. Unfortunately, sufficient attention has not been paid to the inconsistencies in the depictions presented nor how facial approximation techniques may be affecting the legitimacy of the knowledge disseminated through their use. The primary aim of this thesis was to develop more reliable methods for approximating the facial soft tissues of Plio-Pleistocene hominids. This was accomplished by identifying bone and soft tissue covariation patterns in the head of primates, including modern humans, and applying these relationships to Plio-Pleistocene hominid skulls. The overarching hypothesis for this thesis was that if homogeneity of covariation between soft tissues and its underlying bone can be observed among primate species, including modern humans, then these relationships can be extrapolated to Plio-Pleistocene hominids. Such relationships will improve the biological accuracy of their depictions and reduce the problem of inconsistency currently burdening the practice of ancient hominid facial approximation. In Chapter II, it will be shown how archaic hominid facial approximation, as it had been established before the restorative findings of this thesis, had become a domain of artists, who included various theoretical interpretations of human evolution into the facial approximations they produced without questioning their scientific legitimacy. Chapters III and IV showcase how artistic intuitionism no longer suffices to illustrate the facial appearance of our ancestors. In these chapters, new statistical methods that more reliably approximate the facial soft tissue thicknesses for Chimpanzees (Pan troglodytes), Bonobos (Pan paniscus), and by extension other Pliocene hominids, such as Australopithecus africanus, are presented. In addition, new methods for predicting nasal protrusions for all African great apes, modern humans, and by extension all ancestors leading to these clades are also presented. Finally, in chapter 5, general thoughts on some lingering complications and the future of the practice of hominid facial approximation are discussed. The original contributions to knowledge contained within this thesis could not have occurred without challenging the status quo. By hypothesising that the facial soft tissues Plio-Pleistocene hominids could be scientifically reconstructed this thesis has made new discoveries that has in-turn encouraged the field to advance into an empirical discipline from one that was predominately an intuitive artistic activity. Thus, this thesis marks the beginning of a new era of evolutionary reconstructions in the field of biological anthropology.Thesis (Ph.D.) -- University of Adelaide, Adelaide Medical School, 202

On Language Cognition Relations and Evolution of Language

One can understand the importance of language with its relation to mental activities such as memory and thinking. Language, a crucial human ability, has long attracted the attention of various theorists and philosophers. Language, by its nature, interacts with many biological, cultural and psychological factors. This article has drawn a general framework by bringing together the views from disciplines such as linguistics, psychology, anthropology, biology and neuroscience. On the one hand, while the theoretical opinions about language are included, on the other hand, language is discussed in the context of the changes we went through by separating from our common ancestor in the evolution process. When dealing with language, it is possible to talk about our differences from animals, the interaction of language with our cognitive processes and its organization in the brain. The views put forward by philosophers such as Plato and Descartes about the relationship between language and cognitions have expanded by Chomsky, Pinker, Dunbar and others on the evolution of language. In this article, evolutionary psychology, which strives to understand language and its relationship with cognitions, is emphasized by combining the data of modern evolutionary biology and cognitive psychology. Language is acquired quickly and without the intense need for learning experiences, thanks to innate schemas, suggests that evolution formed these schemas. According to another view, the influence of the environment and culture gains importance instead of innatism. In addition, different opinions on the evolution of language are briefly discussed. Discussion topics include triggers of language development in evolution. These are related to biological and cultural influences, influences of vocalization and hand gestures on language. When thinking about language and its evolution, it is inevitable to observe and examine cognitive processes and thought. Multidisciplinary studies can also provide important information about the evolution of language while trying to understand the complex relationship between language and cognition

Biotechnology to Combat COVID-19

This book provides an inclusive and comprehensive discussion of the transmission, science, biology, genome sequencing, diagnostics, and therapeutics of COVID-19. It also discusses public and government health measures and the roles of media as well as the impact of society on the ongoing efforts to combat the global pandemic. It addresses almost every topic that has been studied so far in the research on SARS-CoV-2 to gain insights into the fundamentals of the disease and mitigation strategies. This volume is a useful resource for virologists, epidemiologists, biologists, medical professionals, public health and government professionals, and all global citizens who have endured and battled against the pandemic