scholarly journals Senescence in immunity against helminth parasites predicts adult mortality in a wild mammal

Science ◽  
2019 ◽  
Vol 365 (6459) ◽  
pp. 1296-1298 ◽  
Author(s):  
H. Froy ◽  
A. M. Sparks ◽  
K. Watt ◽  
R. Sinclair ◽  
F. Bach ◽  
...  
Keyword(s):  
Natural Populations ◽  
Adult Mortality ◽  
Modern Human ◽  
Laboratory Animals ◽  
Adult Survival ◽  
Human Populations ◽  
Helminth Parasites ◽  
Overwinter Mortality ◽  
Antibody Levels ◽  
Nematode Worm

Our understanding of the deterioration in immune function in old age—immunosenescence—derives principally from studies of modern human populations and laboratory animals. The generality and significance of this process for systems experiencing complex, natural infections and environmental challenges are unknown. Here, we show that late-life declines in an important immune marker of resistance to helminth parasites in wild Soay sheep predict overwinter mortality. We found senescence in circulating antibody levels against a highly prevalent nematode worm, which was associated with reduced adult survival probability, independent of changes in body weight. These findings establish a role for immunosenescence in the ecology and evolution of natural populations.

scholarly journals Functional relationship between dental macrowear and diet in Late Pleistocene and recent modern human populations

2018 ◽  
Vol 28 (2) ◽  
pp. 153-161 ◽  
Author(s):  
Luca Fiorenza ◽  
Stefano Benazzi ◽  
Gregorio Oxilia ◽  
Ottmar Kullmer
Keyword(s):  
Late Pleistocene ◽  
Functional Relationship ◽  
Modern Human ◽  
Human Populations

scholarly journals The Genome of a Mongolian Individual Reveals the Genetic Imprints of Mongolians on Modern Human Populations

2014 ◽  
Vol 6 (12) ◽  
pp. 3122-3136 ◽  
Author(s):  
Haihua Bai ◽  
Xiaosen Guo ◽  
Dong Zhang ◽  
Narisu Narisu ◽  
Junjie Bu ◽  
...  
Keyword(s):  
Modern Human ◽  
Human Populations

scholarly journals The effect of life-history and mode of inheritance on neutral genetic variability

2001 ◽  
Vol 77 (2) ◽  
pp. 153-166 ◽  
Author(s):  
BRIAN CHARLESWORTH
Keyword(s):  
Sequence Variation ◽  
Adult Mortality ◽  
Structured Populations ◽  
Human Populations ◽  
Effective Population ◽  
Transmission Modes ◽  
Population Sizes ◽  
Age Structured ◽  
Infinite Sites Model ◽  
Site Diversity

Formulae for the effective population sizes of autosomal, X-linked, Y-linked and maternally transmitted loci in age-structured populations are developed. The approximations used here predict both asymptotic rates of increase in probabilities of identity, and equilibrium levels of neutral nucleotide site diversity under the infinite-sites model. The applications of the results to the interpretation of data on DNA sequence variation in Drosophila, plant, and human populations are discussed. It is concluded that sex differences in demographic parameters such as adult mortality rates generally have small effects on the relative effective population sizes of loci with different modes of inheritance, whereas differences between the sexes in variance in reproductive success can have major effects, either increasing or reducing the effective population size for X-linked loci relative to autosomal or Y-linked loci. These effects need to be accounted for when trying to understand data on patterns of sequence variation for genes with different transmission modes.

Palaeolithic Assemblages associated with Youngest Toba Tuff deposits from the Upper Gundlakamma river basin, Andhra Pradesh, India

2021 ◽  
pp. SP515-2020-187
Author(s):  
Devara Anil ◽  
P. Ajithprasad ◽  
Mahesh Vrushab
Keyword(s):  
River Basin ◽  
Andhra Pradesh ◽  
Modern Human ◽  
Human Populations ◽  
Content Type ◽  
Before And After ◽  
Climatic Impacts ◽  
Supplementary Material ◽  
Human Colonization ◽  
Behavioural Adaptations

AbstractArchaeological and geological remains associated with the Youngest Toba Tuff (YTT) deposits in India are seen as significant proxies for reconstructing 1) Initial modern human colonization of India and 2) Possible climatic impacts of the Toba super-eruption of 74 ka on Indian climate and hominin behaviour. In order to gain further insights into the environmental impacts and behavioural adaptations of human populations in India before and after the Toba eruption, we investigated archaeological horizons associated with the Toba ash beds along the Gundlakamma basin in Prakasam District, Andhra Pradesh, India. Here, lithic artefacts were identified below and above the YTT deposits. The YTT deposits in the Gundlakamma river basin has a maximum thickness of 50 cm, comparatively thinner than those at the better investigated valleys of the adjacent Jurreru and Sagileru in Andhra Pradesh and the Son, Madhya Pradesh, India. Our surveys indicate that the Palaeolithic assemblages associated with YTT deposits from the Gundlakamma river basin can provide significant insights on the issues and debates surrounding the Toba archaeology.Supplementary material at https://doi.org/10.6084/m9.figshare.c.5729449

scholarly journals Testing the utility of dental morphological trait combinations for inferring human neutral genetic variation

2020 ◽  
Vol 117 (20) ◽  
pp. 10769-10777 ◽  
Author(s):  
Hannes Rathmann ◽  
Hugo Reyes-Centeno
Keyword(s):  
Modern Human ◽  
Genomic Variation ◽  
Future Research ◽  
Human Populations ◽  
Dental Morphology ◽  
Genomic Signatures ◽  
Neutral Genetic Variation ◽  
Tooth Form ◽  
Dental Traits ◽  
Population Affinity

Researchers commonly rely on human dental morphological features in order to reconstruct genetic affinities among past individuals and populations, particularly since teeth are often the best preserved part of a human skeleton. Tooth form is considered to be highly heritable and selectively neutral and, therefore, to be an excellent proxy for DNA when none is available. However, until today, it remains poorly understood whether certain dental traits or trait combinations preserve neutral genomic signatures to a greater degree than others. Here, we address this long-standing research gap by systematically testing the utility of 27 common dental traits and >134 million possible trait combinations in reflecting neutral genomic variation in a worldwide sample of modern human populations. Our analyses reveal that not all traits are equally well-suited for reconstructing population affinities. Whereas some traits largely reflect neutral variation and therefore evolved primarily as a result of genetic drift, others can be linked to nonstochastic processes such as natural selection or hominin admixture. We also demonstrate that reconstructions of population affinity based on many traits are not necessarily more reliable than those based on only a few traits. Importantly, we find a set of highly diagnostic trait combinations that preserve neutral genetic signals best (up to x∼r = 0.580; 95% r range = 0.293 to 0.758; P = 0.001). We propose that these trait combinations should be prioritized in future research, as they allow for more accurate inferences about past human population dynamics when using dental morphology as a proxy for DNA.

scholarly journals The early Aurignacian dispersal of modern humans into westernmost Eurasia

2020 ◽  
Vol 117 (41) ◽  
pp. 25414-25422
Author(s):  
Jonathan A. Haws ◽  
Michael M. Benedetti ◽  
Sahra Talamo ◽  
Nuno Bicho ◽  
João Cascalheira ◽  
...  
Keyword(s):  
Iberian Peninsula ◽  
Modern Human ◽  
Human Populations ◽  
Southern Europe ◽  
Modern Humans ◽  
Present Evidence ◽  
Western Margin ◽  
Human Presence ◽  
Human Dispersal ◽  
Central Portugal

Documenting the first appearance of modern humans in a given region is key to understanding the dispersal process and the replacement or assimilation of indigenous human populations such as the Neanderthals. The Iberian Peninsula was the last refuge of Neanderthal populations as modern humans advanced across Eurasia. Here we present evidence of an early Aurignacian occupation at Lapa do Picareiro in central Portugal. Diagnostic artifacts were found in a sealed stratigraphic layer dated 41.1 to 38.1 ka cal BP, documenting a modern human presence on the western margin of Iberia ∼5,000 years earlier than previously known. The data indicate a rapid modern human dispersal across southern Europe, reaching the westernmost edge where Neanderthals were thought to persist. The results support the notion of a mosaic process of modern human dispersal and replacement of indigenous Neanderthal populations.

scholarly journals Archaic mitochondrial DNA inserts in modern day nuclear genomes

BMC Genomics ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Robert Bücking ◽  
Murray P Cox ◽  
Georgi Hudjashov ◽  
Lauri Saag ◽  
Herawati Sudoyo ◽  
...  
Keyword(s):  
Mitochondrial Dna ◽  
Nuclear Dna ◽  
Modern Human ◽  
Sub Saharan Africa ◽  
Next Generation Sequencing Data ◽  
Human Populations ◽  
Sequencing Data ◽  
Modern Humans ◽  
High Coverage ◽  
Nuclear Genomes

Abstract Background Traces of interbreeding of Neanderthals and Denisovans with modern humans in the form of archaic DNA have been detected in the genomes of present-day human populations outside sub-Saharan Africa. Up to now, only nuclear archaic DNA has been detected in modern humans; we therefore attempted to identify archaic mitochondrial DNA (mtDNA) residing in modern human nuclear genomes as nuclear inserts of mitochondrial DNA (NUMTs). Results We analysed 221 high-coverage genomes from Oceania and Indonesia using an approach which identifies reads that map both to the nuclear and mitochondrial DNA. We then classified reads according to the source of the mtDNA, and found one NUMT of Denisovan mtDNA origin, present in 15 analysed genomes; analysis of the flanking region suggests that this insertion is more likely to have happened in a Denisovan individual and introgressed into modern humans with the Denisovan nuclear DNA, rather than in a descendant of a Denisovan female and a modern human male. Conclusions Here we present our pipeline for detecting introgressed NUMTs in next generation sequencing data that can be used on genomes sequenced in the future. Further discovery of such archaic NUMTs in modern humans can be used to detect interbreeding between archaic and modern humans and can reveal new insights into the nature of such interbreeding events.

Sign in / Sign up

Export Citation Format

Share Document