Volume 49, Pages 1-112
23 August 2012
quinta-feira, 9 de agosto de 2012
Journal of Human Evolution
Volume 63, Issue 2, Pages 247-438
August 2012
Five Decades after and : Landscape Paleoanthropology of Plio-Pleistocene Olduvai Gorge, Tanzania
Edited by Robert J. Blumenschine, Fidelis T. Masao, Ian G. Stanistreet and Carl C. Swisher
Volume 63, Issue 3, Pages 439-576
September 2012
terça-feira, 31 de julho de 2012
Mais de 40.000 acessos...
O Núcleo de Arqueologia e Paleoecologia (NAP) da Universidade do Algarve é uma unidade totalmente dedicada ao desenvolvimento, dinamização e divulgação da investigação no domínio da Arqueologia e da Paleoecologia humana.
Os objectivos do NAP são sobretudo a divulgação da disciplina arqueológica em contextos não científicos; a cooperação em projectos e elaboração de novas propostas de trabalho; a intensificação e dinamização dos contactos com sociedades e associações científicas, nacionais e estrangeiras; e a promoção e organização de reuniões científicas (congressos, conferências, cursos, workshops e demais actividades relacionadas).
Desde a primeira publicação, a 11 de Janeiro de 2009, soma-mos mais de 40.000 acessos...
Obrigados a todos os leitores, apoiantes e amigos que visitam este espaço e a todas as pessoas que directa ou indirectamente contribuem para este projecto. Esperamos poder continuar a merecer a vossa preferência e confiança.
Aqui fica o nosso sincero obrigado!
NAP
segunda-feira, 30 de julho de 2012
Quaternary International
Volume 270, Pages 1-156
23 August 2012
Late Pleistocene lifeways, an African perspective: selected presentations, PAA-Safa 2010
Edited by Gerrit L. Dusseldorp and Geeske H.J. Langejans
Geomorphology
Sedimentary fluxes and budgets in natural and anthropogenically modified landscapes – Effects of climate change and land-use change on geomorphic processes
Edited by Achim A. Beylich, Armelle Decaulne and Scott Lamoureux
VI Encuentro de Arqueología Peninsular del Suroeste
O VI Encuentro de Arqueología Peninsular del Suroesteque se celebrará entre el 4 y 6 de octubre de 2012 en Villafranca de los Barros. Además, la información que se va generando se está colgando AQUI.
Rethinking Modern Human Origins
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| Did modern humans evolve suddenly or over a long period of time? Image: Fredrik Sandén/Flickr |
Modern humans, Homo sapiens, originated in Africa sometime between 200,000 and 100,000 years ago. I’ve written that sentence many times. But what if it’s wrong? Paleoanthropologist Tim Weaver of the University of California, Davis argues there might be another way to interpret our species’ beginnings. Instead of a discrete origin event, he suggests in the Journal of Human Evolution that our ancestors’ arrival into the world might have been a lengthy process that occurred over hundreds of thousands of years.
Current thinking says the lineages leading to modern humans and Neanderthals split 400,000 years ago. And then 200,000 years later, Homo sapiens suddenly appeared in Africa. There’s a lot of evidence that seems to support the idea. The earliest fossils assigned to our species date to this time period. Mitochondrial DNA inherited through the maternal line backs up the fossil evidence. Modern people’s mitochondrial DNA can all be traced back to a common ancestor, an “Eve,” that lived 200,000 years ago.
But Weaver says these lines of evidence can also support an alternative scenario, in which the evolution of our species plays out over hundreds of thousands of years between the split from Neanderthals and the expansion of humans out of Africa 60,000 to 50,000 years ago. He uses genetics and mathematical methods to argue his case.
First, he shows how modern people’s mitochondrial DNA could all appear to converge at 200,000 years ago without being the result of a speciation event or a population bottleneck at that time. It’s possible, he says, to get the same picture of modern mitochondrial DNA if the population of breeding adults stayed constant 400,000 to 50,000 years ago—and if the size of that population equaled the average (called the harmonic mean) population size of the successive generations experiencing a theoretical bottleneck 200,000 years ago.
Next, he builds a model of physical evolution to show how a long process could lead to the arrival of modern human traits at about 200,000 years ago. The model follows several assumptions about the genetic basis of physical traits. Weaver also assumes changes over time in human physical traits were the result of mutation and genetic drift (random change) rather than natural selection. (He notes that differences between Neanderthal and modern human skulls, for example, don’t appear to be the result of natural selection.) By modeling successive generations from 400,000 years ago to the present, with each generation equaling 25 years, Weaver finds modern human traits should have appeared in the fossil record 165,000 years ago. That date becomes 198,000 years ago when the generation length is increased to 30 years or 132,000 years ago when the generation length is decreased to 20 years. What that means is both an abrupt speciation event or a long process could explain why modern humans seem to appear in the fossil record 200,000 years ago.
Weaver’s purpose with this work, however, is not necessarily to prove that modern human origins was a long, drawn out affair. He writes:
At the moment, both discrete event and lengthy process models appear to be compatible with the available evidence. My goal is simply to show that lengthy process models are consistent with current biological evidence and to heighten awareness of the implications of these models for understanding modern human origins.
One of those implications: If it turns out the arrival of humans was a lengthy process, Weaver says, it means nothing “special” happened 200,000 years ago to cause the birth of our species.
segunda-feira, 23 de julho de 2012
Nota preliminar sobre el IV Seminario de Tecnología Prehistórica (2012): "La agricultura prehistórica: Metodología de investigación"
Dear Colleagues and friends,
With this preliminary note, we want to communicate the future celebration (late fall 2012) of the "IV Prehistoric Technology Seminar", organized by the Institución Mila y Fontanals (CSIC). We beg maximum dissemination of it. On this occasion, the theme will address research methodologies on prehistoric agricultural techniques and technology.Provisional data for the seminar:
- Preliminary title: "IV Prehistoric Technology Seminar: Prehistoric Agriculture: Research Methodology."
- Date of Celebration: 6 to 9 November 2012
- Venue: Institution Mila y Fontanals, CSIC (Barcelona)
Faculty and preliminary titles of the sessions:
- Juan José Ibáñez: El origen de la Agricultura en el Próximo Oriente: Cambio, adopción y proceso de difusión.
- Jesus Emilio González: Técnicas y útiles agrícolas relacionados con el procesado de los cereales
- Juan F. Gibaja: Las técnicas de siega
- Pedro Ferrio Díaz: Los estudios de isótopos aplicados al estudio de la agricultura prehistórica.
- Antonio López: Los análisis polínicos: Procesos agrícolas, territorios de explotación y modificación del paisaje.
- Natalia Alonso: Sistemas de almacenaje. Experimentación y Arqueología.
- Leonor Peña: La Etnoarqueología como medio de aproximación al estudio de las técnicas y sistemas de procesado de los cereales.
- Ramón Buxó: Aproximación al conocimiento sobre la agricultura a partir de los estudios carpológicos.
- Hugo Oliveira: Los estudios genéticos aplicados a las prácticas agrícolas prehistóricas.
- Ferrán Antolín: Análisis cuantitativos y métodos de muestreo en el estudio de semillas.
- Karen Hardy y Les Copeland: El análisis de almidones aplicado al conocimiento de las sociedades agricultoras.
- Marco Madella, Carla Lancelotti y Debora Zurro: Phytoliths as a mean to investigate agricultural plants, systems and tools.
- Welmoed A. Out: Archaeobotany of agricultural societies: the case study of Dutch wetland sites in the process of neolithisation.
- Raquel Piqué y Trinidad Escoriza: Arte rupestre y agricultura.
- Oriol López: Estudio de los palos cavadores empleados en el trabajo agrícola: el caso del asentamiento neolítico de La Draga.
As usual, this seminar involves a special concern for the active participation of the students. In that sense, it will encourage alumni to put together specific issues of their own investigations, in relation to the Seminar's theme (research methodologies in relation to prehistoric agricultural techniques and technology).
In the near future will offer more information.
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domingo, 22 de julho de 2012
sexta-feira, 20 de julho de 2012
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