Reconstructing the Deep Population History of Central and South America

We report genome-wide ancient DNA from 49 individuals forming four parallel time transects in Belize, Brazil, the Central Andes, and the Southern Cone, each dating to at least 9,000 years ago. The common ancestral population radiated rapidly from just one of the two early branches that contributed to Native Americans today. We document two previously unappreciated streams of gene flow between North and South America. One affected the Central Andes by 4,200 years ago, while the other explains an affinity between the oldest North American genome associated with the Clovis culture and the oldest Central and South Americans from Chile, Brazil, and Belize. However, this was not the primary source for later South Americans, as the other ancient individuals derive from lineages without specific affinity to the Clovis-associated genome, suggesting a population replacement that began at least 9,000 years ago and was followed by substantial population continuity in multiple regions

Estratégias de aprendizagem e fatores motivacionais relacionados Learning strategies and related motivational factors

O estudo sobre aprendizagem autorregulada de uma perspectiva sociocognitiva tem integrado fatores cognitivos, metacognitivos, afetivos e motivacionais. Um dos constructos mais investigados nesta área é o de estratégias de aprendizagem, pois seu uso pelos estudantes é considerado um importante indicativo do nível de autorregulação. Nota-se que embora muitos alunos conheçam um repertório de estratégias, nem sempre relatam utilizá-las com frequência. Assume-se, portanto, que esta atividade requer esforço e é marcadamente afetada pela motivação do aluno. Dessa forma, tem-se como finalidade neste artigo, discutir a relação entre estratégias de aprendizagem e algumas variáveis motivacionais que têm sido sistematicamente relacionadas a este constructo: autoeficácia, metas de realização e valor da tarefa.<br>The study about self-regulated learning from a socio-cognitive perspective has integrated cognitive, metacognitive, affective and motivational aspects. Learning strategy has been one of the most investigated constructs in this area, because its use by students is considered a relevant indicative of the self-regulation level. It has been noted that although many students know different strategies, they do not relate to use them frequently. Therefore, it is assumed that this activity requires effort and is markedly affected by students' motivation. For that reason, this article aims to discuss the relation between learning strategies and some motivational variables that have been systematically related to this construct: self-efficacy, achievement goals and task-value

Reconstructing the Deep Population History of Central and South America.

We report genome-wide ancient DNA from 49 individuals forming four parallel time transects in Belize, Brazil, the Central Andes, and the Southern Cone, each dating to at least ∼9,000 years ago. The common ancestral population radiated rapidly from just one of the two early branches that contributed to Native Americans today. We document two previously unappreciated streams of gene flow between North and South America. One affected the Central Andes by ∼4,200 years ago, while the other explains an affinity between the oldest North American genome associated with the Clovis culture and the oldest Central and South Americans from Chile, Brazil, and Belize. However, this was not the primary source for later South Americans, as the other ancient individuals derive from lineages without specific affinity to the Clovis-associated genome, suggesting a population replacement that began at&nbsp;least 9,000 years ago and was followed by substantial population continuity in multiple regions

Reconstructing the Deep Population History of Central and South America.

We report genome-wide ancient DNA from 49 individuals forming four parallel time transects in Belize, Brazil, the Central Andes, and the Southern Cone, each dating to at least ∼9,000 years ago. The common ancestral population radiated rapidly from just one of the two early branches that contributed to Native Americans today. We document two previously unappreciated streams of gene flow between North and South America. One affected the Central Andes by ∼4,200 years ago, while the other explains an affinity between the oldest North American genome associated with the Clovis culture and the oldest Central and South Americans from Chile, Brazil, and Belize. However, this was not the primary source for later South Americans, as the other ancient individuals derive from lineages without specific affinity to the Clovis-associated genome, suggesting a population replacement that began at least 9,000 years ago and was followed by substantial population continuity in multiple regions