scholarly journals Mosaic evolution and the pattern of transitions in the hominin lineage

2016 ◽  
Vol 371 (1698) ◽  
pp. 20150244 ◽  
Author(s):  
Robert A. Foley
Keyword(s):  
Human Evolution ◽  
Eukaryotic Cell ◽  
Major Transitions ◽  
Major Transition ◽  
Novel Taxa ◽  
The Rich ◽  
Four Levels ◽  
Living Organisms ◽  
The Impact ◽  
Major Transitions In Evolution

Humans are uniquely unique, in terms of the extreme differences between them and other living organisms, and the impact they are having on the biosphere. The evolution of humans can be seen, as has been proposed, as one of the major transitions in evolution, on a par with the origins of multicellular organisms or the eukaryotic cell (Maynard Smith & Szathmáry 1997 Major transitions in evolution ). Major transitions require the evolution of greater complexity and the emergence of new evolutionary levels or processes. Does human evolution meet these conditions? I explore the diversity of evidence on the nature of transitions in human evolution. Four levels of transition are proposed—baseline, novel taxa, novel adaptive zones and major transitions—and the pattern of human evolution considered in the light of these. The primary conclusions are that changes in human evolution occur continuously and cumulatively; that novel taxa and the appearance of new adaptations are not clustered very tightly in particular periods, although there are three broad transitional phases (Pliocene, Plio-Pleistocene and later Quaternary). Each phase is distinctive, with the first based on ranging and energetics, the second on technology and niche expansion, and the third on cognition and cultural processes. I discuss whether this constitutes a ‘major transition’ in the context of the evolutionary processes more broadly; the role of behaviour in evolution; and the opportunity provided by the rich genetic, phenotypic (fossil morphology) and behavioural (archaeological) record to examine in detail major transitions and the microevolutionary patterns underlying macroevolutionary change. It is suggested that the evolution of the hominin lineage is consistent with a mosaic pattern of change. This article is part of the themed issue ‘Major transitions in human evolution’.

scholarly journals The origins of the Acheulean: past and present perspectives on a major transition in human evolution

2016 ◽  
Vol 371 (1698) ◽  
pp. 20150245 ◽  
Author(s):  
Ignacio de la Torre
Keyword(s):  
Human Evolution ◽  
Evolutionary History ◽  
Homo Erectus ◽  
Major Transitions ◽  
Current State ◽  
Major Transition ◽  
Hard Evidence ◽  
History Of ◽  
Origins Research ◽  
Cumulative Knowledge

The emergence of the Acheulean from the earlier Oldowan constitutes a major transition in human evolution, the theme of this special issue. This paper discusses the evidence for the origins of the Acheulean, a cornerstone in the history of human technology, from two perspectives; firstly, a review of the history of investigations on Acheulean research is presented. This approach introduces the evolution of theories throughout the development of the discipline, and reviews the way in which cumulative knowledge led to the prevalent explanatory framework for the emergence of the Acheulean. The second part presents the current state of the art in Acheulean origins research, and reviews the hard evidence for the appearance of this technology in Africa around 1.7 Ma, and its significance for the evolutionary history of Homo erectus . This article is part of the themed issue ‘Major transitions in human evolution’.

scholarly journals Noise-driven cell differentiation and the emergence of spatiotemporal patterns

2017 ◽  
Author(s):  
Hadiseh Safdari ◽  
Ata Kalirad ◽  
Cristian Picioreanu ◽  
Rouzbeh Tusserkani ◽  
Bahram Goliaei ◽  
...  
Keyword(s):  
Cell Aggregation ◽  
Self Organization ◽  
Major Transitions ◽  
Evolutionary Origins ◽  
Mechanistic Approach ◽  
Major Transition ◽  
Brave New World ◽  
Multicellular Organisms ◽  
Major Transitions In Evolution ◽  
Biological Innovations

AbstractOne of the major transitions in evolution is the step from unicellularity into the brave new world of multicellularity. To understand this feat, one has to fathom two main characteristics of multicellular organisms: differentiation and self-organization. Any explanation concerning this major transition should involve mechanisms that can simultaneously explain the marvellous intricacies manifest in the aforementioned characteristics, and an account of the evolution of such traits. Here we propose a noise-driven differentiation (NDD) model. The reliance on noise, in place of a more mechanistic approach, makes the NDD model a more suitable approach to explain differentiation and self-organization. Furthermore, our model sheds some light on the possible evolutionary origins of these biological innovations. To test the NDD model, we utilize a model of cell aggregation. The behavior of this model of cell aggregation is in concert with the NDD model.

The Major Transitions in Evolution

1997 ◽  
Author(s):  
John Maynard Smith ◽  
Eors Szathmary
Keyword(s):  
Full Range ◽  
Evolution Of Cooperation ◽  
Major Transitions ◽  
Insect Societies ◽  
Wide Range ◽  
Major Transition ◽  
Life Itself ◽  
History Of ◽  
Emergence Of Cooperation ◽  
Multicellular Organisms

Over the history of life there have been several major changes in the way genetic information is organized and transmitted from one generation to the next. These transitions include the origin of life itself, the first eukaryotic cells, reproduction by sexual means, the appearance of multicellular plants and animals, the emergence of cooperation and of animal societies, and the unique language ability of humans. This ambitious book provides the first unified discussion of the full range of these transitions. The authors highlight the similarities between different transitions--between the union of replicating molecules to form chromosomes and of cells to form multicellular organisms, for example--and show how understanding one transition sheds light on others. They trace a common theme throughout the history of evolution: after a major transition some entities lose the ability to replicate independently, becoming able to reproduce only as part of a larger whole. The authors investigate this pattern and why selection between entities at a lower level does not disrupt selection at more complex levels. Their explanation encompasses a compelling theory of the evolution of cooperation at all levels of complexity. Engagingly written and filled with numerous illustrations, this book can be read with enjoyment by anyone with an undergraduate training in biology. It is ideal for advanced discussion groups on evolution and includes accessible discussions of a wide range of topics, from molecular biology and linguistics to insect societies.

The effects of debt restructurings on income inequality in the developing world

2021 ◽  
pp. 135406612110014
Author(s):  
Glen Biglaiser ◽  
Ronald J. McGauvran
Keyword(s):  
Developing Countries ◽  
Panel Data ◽  
Income Inequality ◽  
Income Distribution ◽  
Government Spending ◽  
Tax Reform ◽  
Social Spending ◽  
The Poor ◽  
The Rich ◽  
The Impact

Developing countries, saddled with debts, often prefer investors absorb losses through debt restructurings. By not making full repayments, debtor governments could increase social spending, serving poorer constituents, and, in turn, lowering income inequality. Alternatively, debtor governments could reduce taxes and cut government spending, bolstering the assets of the rich at the expense of the poor. Using panel data for 71 developing countries from 1986 to 2016, we assess the effects of debt restructurings on societal income distribution. Specifically, we study the impact of debt restructurings on social spending, tax reform, and income inequality. We find that countries receiving debt restructurings tend to use their newly acquired economic flexibility to reduce taxes and lower social spending, worsening income inequality. The results are also robust to different model specifications. Our study contributes to the globalization and the poor debate, suggesting the economic harm caused to the less well-off following debt restructurings.

scholarly journals Rethinking success, integrity, and culture in research (part 2) — a multi-actor qualitative study on problems of science

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Noémie Aubert Bonn ◽  
Wim Pinxten
Keyword(s):  
Research Misconduct ◽  
Research Integrity ◽  
Research Culture ◽  
Structured Interviews ◽  
Community Members ◽  
Questionable Research Practices ◽  
Research Problems ◽  
The Rich ◽  
Research Students ◽  
The Impact

Abstract Background Research misconduct and questionable research practices have been the subject of increasing attention in the past few years. But despite the rich body of research available, few empirical works also include the perspectives of non-researcher stakeholders. Methods We conducted semi-structured interviews and focus groups with policy makers, funders, institution leaders, editors or publishers, research integrity office members, research integrity community members, laboratory technicians, researchers, research students, and former-researchers who changed career to inquire on the topics of success, integrity, and responsibilities in science. We used the Flemish biomedical landscape as a baseline to be able to grasp the views of interacting and complementary actors in a system setting. Results Given the breadth of our results, we divided our findings in a two-paper series with the current paper focusing on the problems that affect the integrity and research culture. We first found that different actors have different perspectives on the problems that affect the integrity and culture of research. Problems were either linked to personalities and attitudes, or to the climates in which researchers operate. Elements that were described as essential for success (in the associate paper) were often thought to accentuate the problems of research climates by disrupting research culture and research integrity. Even though all participants agreed that current research climates need to be addressed, participants generally did not feel responsible nor capable of initiating change. Instead, respondents revealed a circle of blame and mistrust between actor groups. Conclusions Our findings resonate with recent debates, and extrapolate a few action points which might help advance the discussion. First, the research integrity debate must revisit and tackle the way in which researchers are assessed. Second, approaches to promote better science need to address the impact that research climates have on research integrity and research culture rather than to capitalize on individual researchers’ compliance. Finally, inter-actor dialogues and shared decision making must be given priority to ensure that the perspectives of the full research system are captured. Understanding the relations and interdependency between these perspectives is key to be able to address the problems of science. Study registration https://osf.io/33v3m

scholarly journals Changes Caused by Low Doses of Bisphenol A (BPA) in the Neuro-Chemistry of Nerves Located in the Porcine Heart

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 780
Author(s):  
Krystyna Makowska ◽  
Slawomir Gonkowski
Keyword(s):  
Bisphenol A ◽  
Endocrine Disruptor ◽  
Sympathetic Innervation ◽  
Daily Intake ◽  
Everyday Objects ◽  
Living Organisms ◽  
The Impact ◽  
Heart Wall ◽  
Cholinergic Structures

Bisphenol A (BPA) contained in plastics used in the production of various everyday objects may leach from these items and contaminate food, water and air. As an endocrine disruptor, BPA negatively affects many internal organs and systems. Exposure to BPA also contributes to heart and cardiovascular system dysfunction, but many aspects connected with this activity remain unknown. Therefore, this study aimed to investigate the impact of BPA in a dose of 0.05 mg/kg body weight/day (in many countries such a dose is regarded as a tolerable daily intake–TDI dose of BPA–completely safe for living organisms) on the neurochemical characterization of nerves located in the heart wall using the immunofluorescence technique. The obtained results indicate that BPA (even in such a relatively low dose) increases the number of nerves immunoreactive to neuropeptide Y, substance P and tyrosine hydroxylase (used here as a marker of sympathetic innervation). However, BPA did not change the number of nerves immunoreactive to vesicular acetylcholine transporter (used here as a marker of cholinergic structures). These observations suggest that changes in the heart innervation may be at the root of BPA-induced circulatory disturbances, as well as arrhythmogenic and/or proinflammatory effects of this endocrine disruptor. Moreover, changes in the neurochemical characterization of nerves in the heart wall may be the first sign of exposure to BPA.

Cooperation dynamics of polycentric climate governance

2015 ◽  
Vol 25 (13) ◽  
pp. 2503-2517 ◽  
Author(s):  
Vítor V. Vasconcelos ◽  
Francisco C. Santos ◽  
Jorge M. Pacheco
Keyword(s):  
Common Good ◽  
Evolutionary Game ◽  
Wealth Inequality ◽  
Small Scale ◽  
The Poor ◽  
Viable Solution ◽  
The Rich ◽  
Global Coordination ◽  
The Impact ◽  
Climate Change Governance

Global coordination for the preservation of a common good, such as climate, is one of the most prominent challenges of modern societies. In this manuscript, we use the framework of evolutionary game theory to investigate whether a polycentric structure of multiple small-scale agreements provides a viable solution to solve global dilemmas as climate change governance. We review a stochastic model which incorporates a threshold game of collective action and the idea of risky goods, capturing essential features unveiled in recent experiments. We show how reducing uncertainty both in terms of the perception of disaster and in terms of goals induce a transition to cooperation. Taking into account wealth inequality, we explore the impact of the homophily, potentially present in the network of influence of the rich and the poor, in the different contributions of the players. Finally, we discuss the impact of polycentric sanctioning institutions, showing how such a scenario also proves to be more efficient than a single global institution.

scholarly journals Evaluating the role of contracting and expanding rainforest in initiating cycles of speciation across the Isthmus of Panama

2012 ◽  
Vol 279 (1742) ◽  
pp. 3520-3526 ◽  
Author(s):  
Brian Tilston Smith ◽  
Amei Amei ◽  
John Klicka
Keyword(s):  
Bird Species ◽  
Tropical Regions ◽  
Isthmus Of Panama ◽  
Species Pairs ◽  
The Matrix ◽  
High Species Richness ◽  
The Rich ◽  
The Tropics ◽  
The Impact

Climatic and geological changes across time are presumed to have shaped the rich biodiversity of tropical regions. However, the impact climatic drying and subsequent tropical rainforest contraction had on speciation has been controversial because of inconsistent palaeoecological and genetic data. Despite the strong interest in examining the role of climatic change on speciation in the Neotropics there has been few comparative studies, particularly, those that include non-rainforest taxa. We used bird species that inhabit humid or dry habitats that dispersed across the Panamanian Isthmus to characterize temporal and spatial patterns of speciation across this barrier. Here, we show that these two assemblages of birds exhibit temporally different speciation time patterns that supports multiple cycles of speciation. Evidence for these cycles is further corroborated by the finding that both assemblages consist of ‘young’ and ‘old’ species, despite dry habitat species pairs being geographically more distant than pairs of humid habitat species. The matrix of humid and dry habitats in the tropics not only allows for the maintenance of high species richness, but additionally this study suggests that these environments may have promoted speciation. We conclude that differentially expanding and contracting distributions of dry and humid habitats was probably an important contributor to speciation in the tropics.

scholarly journals The Origin and Evolution of Language and the Propagation of Organization

1970 ◽  
Vol 5 (2) ◽  
pp. 75-81 ◽  
Author(s):  
Robert K. Logan
Keyword(s):  
Knowledge Management ◽  
New Media ◽  
Evolution Of Language ◽  
Origin And Evolution ◽  
Language And Culture ◽  
Origin Of Language ◽  
Engineering Problems ◽  
Living Organisms ◽  
The Impact

In this presentation we will study propagating organization. We begin by examining the evolution and origin of language by briefly reviewing the impact of the phonetic alphabet (Logan 2004a), the evolution of notated language (Logan 2004b), the origin of language and culture (Logan 2006, 2007), the role of collaboration in knowledge management (Logan and Stokes 2004), the impact of “new media” (Logan in preparation). We will then connect this work to the propagating organization of all living organisms (Kauffman et al. in press) where we will show that information in biotic systems are the constraints that instruct living organisms how to operate. We will demonstrate that instructional or biotic information is quite different than the classical notion of information Shannon developed for addressing engineering problems in telecommunications. We also will show that biosemiosis is in some sense equivalent to propagating organization (Kauffman et al. in press). We then conclude our presentation with the speculation that there exist at least seven levels of biosemiosis.

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