scholarly journals Dissecting dynamics and differences of selective pressures in the evolution of human pigmentation

Biology Open ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. bio056523
Author(s):  
Xin Huang ◽  
Sijia Wang ◽  
Li Jin ◽  
Yungang He
Keyword(s):  
Natural Selection ◽  
Complex Trait ◽  
Directional Selection ◽  
Genotype Data ◽  
Population Groups ◽  
Selective Pressures ◽  
African Populations ◽  
The World ◽  
Dark Pigmentation ◽  
Time Periods

ABSTRACTHuman pigmentation is a highly diverse and complex trait among populations and has drawn particular attention from both academic and non-academic investigators for thousands of years. Previous studies detected selection signals in several human pigmentation genes, but few studies have integrated contribution from multiple genes to the evolution of human pigmentation. Moreover, none has quantified selective pressures on human pigmentation over epochs and between populations. Here, we dissect dynamics and differences of selective pressures during different periods and between distinct populations with new approaches. We use genotype data of 19 genes associated with human pigmentation from 17 publicly available datasets and obtain data for 2346 individuals of six representative population groups from across the world. Our results quantify the strength of natural selection on light pigmentation not only in modern Europeans (0.0259/generation) but also in proto-Eurasians (0.00650/generation). Our results also suggest that several derived alleles associated with human dark pigmentation may be under positive directional selection in some African populations. Our study provides the first attempt to quantitatively investigate the dynamics of selective pressures during different time periods in the evolution of human pigmentation.This article has an associated First Person interview with the first author of the article.

scholarly journals Dissecting dynamics and differences of selective pressures in the evolution of human pigmentation

2018 ◽  
Author(s):  
Xin Huang ◽  
Yungang He ◽  
Sijia Wang ◽  
Li Jin
Keyword(s):  
Natural Selection ◽  
Ultraviolet Radiation ◽  
Complex Traits ◽  
Complex Trait ◽  
Color Variation ◽  
Human Populations ◽  
Selective Pressures ◽  
Multiple Genes ◽  
Dark Pigmentation ◽  
Time Periods

AbstractHuman pigmentation is a highly diverse and complex trait among populations, and has drawn particular attention from both academic and non-academic investigators for thousands of years. Previous studies detected selection signals in several human pigmentation genes, but few studies have integrated contribution from multiple genes to the evolution of human pigmentation. Moreover, none has quantified selective pressures on human pigmentation over epochs and between populations. Here, we dissect dynamics and differences of selective pressures during different periods and between distinct populations with new approaches. We propose a new model with multiple populations to estimate historical selective pressures by summarizing selective pressures on multiple genes. We use genotype data of 19 genes associated with human pigmentation from 17 datasets, and obtain data for 2346 individuals of six representative population groups from worldwide. Our results quantify selective pressures on light pigmentation not only in modern Europeans (0.0249/generation) but also in proto-Eurasians (0.00665/generation). Our results also support several derived alleles associated with human dark pigmentation may under directional selection by quantifying differences of selective pressures between populations. Our study provides a first attempt to quantitatively investigate the dynamics of selective pressures during different time periods in the evolution of human pigmentation, and may facilitate studies of the evolution of other complex traits.Author SummaryThe color variation of human skin, hair, and eye is affected by multiple genes with different roles. This diversity may be shaped by natural selection and adapted for ultraviolet radiation in different environments around the world. As human populations migrated out from Africa, the ultraviolet radiation in the environment they encountered also changed. It is possible that the selective pressures on human pigmentation varied throughout human evolutionary history. In this study, we develop a new approach and estimate historical selective pressures on light pigmentation not only in modern Europeans but also in proto-Eurasians. To our best knowledge, this is the first study that quantifies selective pressures during different time periods in the evolution of human pigmentation. Besides, we provide statistical evidence to support several genes associated with human dark pigmentation may be favored by natural selection. Thus, natural selection may not only affect light pigmentation in Eurasians, but also influence dark pigmentation in Africans.

scholarly journals Modelling the spatiotemporal spread of beneficial alleles using ancient genomes

2021 ◽  
Author(s):  
Rasa A Muktupavela ◽  
Martin Petr ◽  
Laure S&eacutegurel ◽  
Thorfinn Sand Korneliussen ◽  
John Novembre ◽  
...  
Keyword(s):  
Natural Selection ◽  
Diffusion Rate ◽  
Complete Understanding ◽  
Sequencing Technologies ◽  
The World ◽  
Time Periods ◽  
Frequency Changes ◽  
Low Coverage ◽  
Beneficial Allele ◽  
And Diffusion

Ancient genome sequencing technologies now provide the opportunity to study natural selection in unprecedented detail. Rather than making inferences from indirect footprints left by selection in present-day genomes, we can directly observe whether a given allele was present or absent in a particular region of the world at almost any period of human history within the last 10,000 years. Methods for studying selection using ancient genomes often rely on partitioning individuals into discrete time periods or regions of the world. However, a complete understanding of natural selection requires more nuanced statistical methods which can explicitly model allele frequency changes in a continuum across space and time. Here we introduce a method for inferring the spread of a beneficial allele across a landscape using two-dimensional partial differential equations. Unlike previous approaches, our framework can handle time-stamped ancient samples, as well as genotype likelihoods and pseudohaploid sequences from low-coverage genomes. We apply the method to a panel of published ancient West Eurasian genomes, to produce dynamic maps showcasing the inferred spread of candidate beneficial alleles over time and space. We also provide estimates for the strength of selection and diffusion rate for each of these alleles. Finally, we highlight possible avenues of improvement for accurately tracing the spread of beneficial alleles in more complex scenarios.

Introduction

2020 ◽  
pp. 1-23
Author(s):  
Ben Bradley
Keyword(s):  
Twentieth Century ◽  
Natural Selection ◽  
Molecular Genetics ◽  
Evolutionary Theory ◽  
The Other ◽  
Living World ◽  
The World ◽  
Time Periods ◽  
Over Time

Twentieth-century psychology took a modernist form, giving Darwin’s approach to agency an unscientific look. Meanwhile, twentieth-century biologists were reconstructing evolutionary theory to highlight molecular genetics, reducing Darwin’s far-reaching writings about the living world to one grand idea: natural selection. Advances in biology today, which ground evolutionary thinking in a theory of the organism (or phenotype), find new wisdom in Darwin’s vision of the world. This vision has two axes. One describes the interwoven lives of the creatures who fill a given habitat, making interdependence central—a theatre of agency or ‘struggle for life.’ The other is what that struggle effects over time periods measured in millions of years, namely: evolution. Like his law of natural selection, Darwin’s psychology drew primarily on his understandings of the theatre of agency, whether discussing the actions of humans, animals, or plants—as the chapters of this book will show.

THE EVOLUTION OF FINANCIAL STATEMENT INDEXATION IN BRAZIL

1986 ◽  
Vol 13 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Timothy S. Doupnik
Keyword(s):  
Financial Reporting ◽  
Financial Statement ◽  
The World ◽  
Inflation Accounting ◽  
History Of ◽  
Time Periods

Accounting for inflation is one of the more controversial topics in financial reporting. This paper traces the evolution of the system of inflation accounting used in one of the most highly inflationary economies in the world—Brazil. The history of inflation accounting in Brazil (known as monetary correction) is divided into three time periods: pre-1964, 1964 to 1976, and 1976 to the present. The events pertinent to the system of monetary correction in each of these periods are first discussed and then evaluated. It is shown that the system of monetary correction has been subject to massive political pressures since its inception, but gradual improvements have taken place over the years.

scholarly journals Survey of Radon Concentrations in the University of Granada in Southern Spain

2021 ◽  
Vol 18 (6) ◽  
pp. 2885
Author(s):  
Irene Calvente ◽  
María Isabel Núñez ◽  
Rachid Chahboun Karimi ◽  
Juan Villalba-Moreno
Keyword(s):  
Southern Spain ◽  
World Health ◽  
Maximal Level ◽  
15Th Century ◽  
The World ◽  
Time Periods ◽  
Health Organization ◽  
The University ◽  
Analyze Data ◽  
Radon Concentrations

The objective of this pilot study was to gather and analyze data on radon concentrations in workplaces in three buildings of Granada University (Southern Spain) constructed in different centuries. All measurements were made at basement or ground floor level under normal use conditions except for one space (mineral store), in which measurements were compared between the door closed and open. Measurements were conducted during different time periods between October 2013 and March 2019 with a Radon-Scout PLUS portable Radonmonitor. The duration of continuous recordings at different sites ranged between 42 and 1104 h. Mean accumulated radon concentrations ranged between 12 and 95 Bq/m3, below the maximal level of 300 Bq/m3 set by the World Health Organization (WHO). Relatively high values were recorded in the oldest building (15th century), which was also poorly ventilated. Ventilation appeared to be an important factor in reducing radon levels, especially in areas less exposed to radon, such as Southern Spain.

scholarly journals Sámi indigenous(?) Religion(s)(?)—Some Observations and Suggestions Concerning Term Use

Religions ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 432
Author(s):  
Konsta Kaikkonen
Keyword(s):  
Culturally Sensitive ◽  
Indigenous Religion ◽  
Historical Materials ◽  
Everyday Lives ◽  
Sensitive Topics ◽  
The World ◽  
Great Relevance ◽  
Time Periods ◽  
To Come ◽  
Indigenous Religions

When writing about politically and culturally sensitive topics, term use is of great relevance. Sámi religion is a case in point. Words organise and create the world around us, and labels have direct consequences on how religious phenomena are perceived. Even labelling a phenomenon or an action “religious” carries certain baggage. Term use is, of course, easier when writing about historical materials and describing rituals whose practitioners have been dead for centuries. Nonetheless, contemporary practitioners of age-old rituals or people who use ancient symbols in their everyday lives often see themselves as carriers of old tradition and wish to identify with previous generations regardless of opinions that might deem their actions as “re-enacting”, “neoshamanism”, or “neopaganism”. If, for example, outsider academics wish to deem modern-day Indigenous persons as “neo”-something, issues of power and essentialism blend in with the discourse. This paper critically explores terms used around the Sámi religion in different time periods and attempts to come to suggestions that could solve some of the terminological problems a student of modern practitioners of indigenous religions inevitably faces.

scholarly journals Agrowisata Berkelanjutan Berbasis Kopi di Satria Agrowisata Desa Manukaya, Kecamatana Tampak Siring, Kabupaten Gianyar, Bali (Studi Evolusi Pariwisata)

2020 ◽  
Vol 8 (2) ◽  
pp. 262
Author(s):  
Febrytha Nur Azizah ◽  
I Putu Anom
Keyword(s):  
Natural Selection ◽  
Evolutionary Process ◽  
Secondary Data ◽  
Primary Data ◽  
Tourist Attraction ◽  
Theory Of Evolution ◽  
Alternative Tourism ◽  
The World ◽  
Tourism Activity ◽  
Main Attraction

Agro-tourism is an alternative tourism activity that relies on plantations and agriculture as its main attraction. Along with the development of tourism, agro-tourism has now become an economic driving commodity for the surrounding community, so that agro-tourism is increasingly taken into account in the world of tourism. The development of an agro-tourism can not be separated from the evolutionary process that occurs through various stages of the beginning of the tourist attraction built until now. This study aims to determine the evolution of developments in Satria Agrowisata. The research method used is descriptive qualitative by conducting data collection techniques through online interview as primary data, and conducting online observations as secondary data. The results show that Satria Agrowisata can adapt well to the various changes that exist and continue to innovate in order to survive in the world of tourism until now. In Darwin's theory of evolution, he put forward two key words in his theory, natural selection and adaptation. Natural selection as a mechanism for evolutionary change, and adaptations that occur in its development over time.   Keyword: Evolution, Agrotourism, Satria Agrowisata, Bali.

scholarly journals Meningkatnya Risiko Disabilitas Pada Penduduk Dengan Penyakit Tidak Menular: Analisa Lanjut Riskesdas 2013

2019 ◽  
Vol 21 (4) ◽  
Author(s):  
Isfandari Siti ◽  
Betty Roosihermiatie
Keyword(s):  
World Health Organization ◽  
Communicable Disease ◽  
World Health ◽  
Disability Assessment ◽  
Population Groups ◽  
Younger Age ◽  
The World ◽  
People With Disability ◽  
Health Organization ◽  
Develop Program

Intersectoral approach is essential to develop program for people with disability in Indonesia. Coordination across ministries are necessary to manage this issue. The planning, provision and monitoring of medical and support services as well as program for population groups with disability may require assessment. Purpose of this study is to assess disability in Indonesia. Methods: performing analysis of disability data from 2013 Indonesian Household Health Survey known as Riskesdas. Level of disability obtained from two main population groups: those with and without non communicable disease (NCD). They then divided by age. The World Health Organization Disability Assessment Schedule II (WHODASII) was used to measure disability. Results: contribution of NCD on disability is obvious among older age indicated by higher proportion of disability with NCD. While risk of disability among younger age is unclear, since disability with NCDproportion is lower than disability without NCD. Probably risk of disability among younger age is other than NCD. None of the groups had members with extreme disability on their global WHO-DASII scores. The analysis identifi es target groups for each stakeholder to develop program for people with disability to reach their maximum potential. Abstrak Penanganan penduduk dengan disabilitas membutuhkan keterlibatan lintas kementerian. Diperlukan informasi besar masalah penduduk dengan disabilitas di Indonesia. Analisa bertujuan mengetahui besaran masalah. Metode: analisa deskriptif univariat dan bivariat data disabilitas Riskesdas 2013 untuk memperoleh Informasi disabilitas seluruh penduduk. Selanjutnya dilakukan analisa besaran disabilitas pada penduduk dengan dan tanpa Penyakit Tidak Menular (PTM). Kelompok ini kemudian digolongkan menurut umur. Instrumen The World Health Organization Disability Assessment Schedule II (WHO-DASII) digunakan untuk mengukur disabilitas. Hasil: 18% penduduk Indonesia mengalami disabilitas. Informasi lebih rinci 8,2% mengalami kesulitan ringan, 6,8% kesulitan sedang dan 3% kesulitan berat. Kontribusi PTM terhadap disabilitas terlihat jelas pada kelompok usia 45 tahun atau lebih ditunjukkan dengan lebih tingginya proporsi disabilitas dengan PTM. Sedangkan risiko disabilitas pada kelompok usia sebelum 45 tahun bukan PTM, karena proporsidisabilitas dengan PTM lebih rendah.

scholarly journals InBUy database of Invasive and Alien Species (IAS) in Uruguay: a useful tool to confront this threat to biodiversity

2010 ◽  
Vol 10 (4) ◽  
pp. 205-213 ◽  
Author(s):  
Silvana Masciadri ◽  
Ernesto Brugnoli ◽  
Pablo Muniz
Keyword(s):  
Vascular Plants ◽  
Prevention And Control ◽  
Life Forms ◽  
The World ◽  
Time Periods ◽  
Negative Impacts ◽  
Managed Ecosystems ◽  
Taxonomic Groups ◽  
And Control ◽  
Trees And Shrubs

In Uruguay, as well as in other regions of the world, IAS cause negative impacts on natural and managed ecosystems. The use of databases is a helpful tool to elaborate different strategies for prevention and control, and to develop policies and scientific analyses related to IAS. The database of IAS in Uruguay (InBUy) was developed during two time periods (2006-2007 and 2009-2010). It currently contains information on 33 specialists of different taxonomic groups, 14 research projects, 185 references, 351 species and 4,715 records, with vascular plants having both the highest number of species and records. Among vascular plants, herbaceous life forms are the most strongly represented, followed by trees and shrubs. Within animals, the fishes and mollusks are the most important groups. Analysis of the native distribution areas of IAS showed that most are indigenous from Europe, followed by Asia and Oceania. Data showed that introductions of IAS into Uruguay are mainly intentional (67%), so efforts should be focused on policies and rules in order to control the entrance of exotic organisms and prevent new invasions. The geography of the compiled dataset shows the main impact is along the coastline, where the highest exotic species richness and records occurs, and also the most biological invasions. The InBUy database is up-to-date and has successfully contributed to the creation of an official IAS list for Uruguay and both a National and a Coastal Geographic Information System. It has also been used for developing consciousness about this important threat to biodiversity, at both national and regional scales.

Spencer, Herbert (1820–1903)

2018 ◽  
Author(s):  
Tim S. Gray
Keyword(s):  
New York ◽  
Natural Selection ◽  
Evolutionary Theory ◽  
Industrial Revolution ◽  
Late Nineteenth Century ◽  
Human Society ◽  
Herbert Spencer ◽  
The World ◽  
The Usa ◽  
Late Nineteenth

Herbert Spencer is chiefly remembered for his classical liberalism and his evolutionary theory. His fame was considerable during the mid- to late-nineteenth century, especially in the USA, which he visited in 1882 to be lionized by New York society as the prophetic philosopher of capitalism. In Britain, however, Spencer’s reputation suffered two fatal blows towards the end of his life. First, collectivist legislation was introduced to protect citizens from the ravages of the industrial revolution, and Spencer’s spirited defence of economic laissez-faire became discredited. Second, his evolutionary theory, which was based largely on the Lamarckian principle of the inheritance of organic modifications produced by use and disuse, was superseded by Darwin’s theory of natural selection. Nearly a century after his death, however, there is renewed interest in his ideas, partly because the world has become more sympathetic to market philosophies, and partly because the application of evolutionary principles to human society has become fashionable once more.

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