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1.
Nature ; 527(7577): 226-30, 2015 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-26560301

RESUMEN

The pressures on honeybee (Apis mellifera) populations, resulting from threats by modern pesticides, parasites, predators and diseases, have raised awareness of the economic importance and critical role this insect plays in agricultural societies across the globe. However, the association of humans with A. mellifera predates post-industrial-revolution agriculture, as evidenced by the widespread presence of ancient Egyptian bee iconography dating to the Old Kingdom (approximately 2400 BC). There are also indications of Stone Age people harvesting bee products; for example, honey hunting is interpreted from rock art in a prehistoric Holocene context and a beeswax find in a pre-agriculturalist site. However, when and where the regular association of A. mellifera with agriculturalists emerged is unknown. One of the major products of A. mellifera is beeswax, which is composed of a complex suite of lipids including n-alkanes, n-alkanoic acids and fatty acyl wax esters. The composition is highly constant as it is determined genetically through the insect's biochemistry. Thus, the chemical 'fingerprint' of beeswax provides a reliable basis for detecting this commodity in organic residues preserved at archaeological sites, which we now use to trace the exploitation by humans of A. mellifera temporally and spatially. Here we present secure identifications of beeswax in lipid residues preserved in pottery vessels of Neolithic Old World farmers. The geographical range of bee product exploitation is traced in Neolithic Europe, the Near East and North Africa, providing the palaeoecological range of honeybees during prehistory. Temporally, we demonstrate that bee products were exploited continuously, and probably extensively in some regions, at least from the seventh millennium cal BC, likely fulfilling a variety of technological and cultural functions. The close association of A. mellifera with Neolithic farming communities dates to the early onset of agriculture and may provide evidence for the beginnings of a domestication process.


Asunto(s)
Apicultura/historia , Abejas , Ceras/análisis , Ceras/historia , África del Norte , Animales , Arqueología , Cerámica/química , Cerámica/historia , Europa (Continente) , Agricultores/historia , Mapeo Geográfico , Historia Antigua , Lípidos/análisis , Lípidos/química , Medio Oriente , Análisis Espacio-Temporal , Ceras/química
2.
Proc Natl Acad Sci U S A ; 113(2): 368-73, 2016 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-26712024

RESUMEN

The Neolithic and Bronze Age transitions were profound cultural shifts catalyzed in parts of Europe by migrations, first of early farmers from the Near East and then Bronze Age herders from the Pontic Steppe. However, a decades-long, unresolved controversy is whether population change or cultural adoption occurred at the Atlantic edge, within the British Isles. We address this issue by using the first whole genome data from prehistoric Irish individuals. A Neolithic woman (3343-3020 cal BC) from a megalithic burial (10.3× coverage) possessed a genome of predominantly Near Eastern origin. She had some hunter-gatherer ancestry but belonged to a population of large effective size, suggesting a substantial influx of early farmers to the island. Three Bronze Age individuals from Rathlin Island (2026-1534 cal BC), including one high coverage (10.5×) genome, showed substantial Steppe genetic heritage indicating that the European population upheavals of the third millennium manifested all of the way from southern Siberia to the western ocean. This turnover invites the possibility of accompanying introduction of Indo-European, perhaps early Celtic, language. Irish Bronze Age haplotypic similarity is strongest within modern Irish, Scottish, and Welsh populations, and several important genetic variants that today show maximal or very high frequencies in Ireland appear at this horizon. These include those coding for lactase persistence, blue eye color, Y chromosome R1b haplotypes, and the hemochromatosis C282Y allele; to our knowledge, the first detection of a known Mendelian disease variant in prehistory. These findings together suggest the establishment of central attributes of the Irish genome 4,000 y ago.


Asunto(s)
Genoma Humano , Migración Humana , Océano Atlántico , ADN/genética , ADN/aislamiento & purificación , Pool de Genes , Haplotipos/genética , Homocigoto , Humanos , Irlanda , Fenotipo , Análisis de Componente Principal , Análisis de Secuencia de ADN , Factores de Tiempo
3.
Science ; 365(6457)2019 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-31488661

RESUMEN

By sequencing 523 ancient humans, we show that the primary source of ancestry in modern South Asians is a prehistoric genetic gradient between people related to early hunter-gatherers of Iran and Southeast Asia. After the Indus Valley Civilization's decline, its people mixed with individuals in the southeast to form one of the two main ancestral populations of South Asia, whose direct descendants live in southern India. Simultaneously, they mixed with descendants of Steppe pastoralists who, starting around 4000 years ago, spread via Central Asia to form the other main ancestral population. The Steppe ancestry in South Asia has the same profile as that in Bronze Age Eastern Europe, tracking a movement of people that affected both regions and that likely spread the distinctive features shared between Indo-Iranian and Balto-Slavic languages.


Asunto(s)
Pueblo Asiatico/genética , Granjas/historia , Migración Humana/historia , Población/genética , Asia Central , Asia Sudoriental , Flujo Génico , Historia Antigua , Humanos , Irán , Análisis de Secuencia de ADN
4.
J Child Adolesc Psychiatr Nurs ; 20(4): 197-208, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17991050

RESUMEN

PURPOSE: This study aims to utilize nursing and other college students in conducting a mentoring project aimed at determining outcomes of behavior and attitude of high-risk middle school students over a 5-year period. METHOD: A quasi-experimental study with a sample of fifth and sixth graders was conducted in which mentored subjects were tested using multiple instruments and school data to identify behavioral and attitudinal outcomes. Statistical analyses were conducted using chi-square and one-way analysis of variance. FINDINGS: Academically below-average males in the treatment group were the only cohort demonstrating significant change across all measures. The magnitude of change in this cohort, however, did significantly affect treatment group outcomes overall. Females in both treatment and control groups reflected similar changes. CONCLUSIONS: Mentoring of schoolchildren is difficult to accomplish using college mentors because of time and schedule commitments. When college mentors are used, grade allocation seems to be a stronger incentive than when payment is the sole reward. Males whose grades are below average demonstrated positive outcomes from the mentoring experience.


Asunto(s)
Actitud , Conducta Infantil , Mentores , Enfermería Pediátrica/educación , Estudiantes/psicología , Análisis de Varianza , Niño , Trastorno Depresivo/prevención & control , Escolaridad , Femenino , Humanos , Estudios Longitudinales , Masculino , Autoimagen , Trastorno de la Conducta Social/prevención & control , Estados Unidos
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