We assembled genome-wide data from 271 ancient Iberians, of whom 176 are from the largely unsampled period after 2000 BCE, thereby providing a high-resolution time transect of the Iberian Peninsula. We document high genetic substructure between northwestern and southeastern hunter-gatherers before the spread of farming. We reveal sporadic contacts between Iberia and North Africa by~2500 BCE and, by~2000 BCE, the replacement of 40% of Iberia's ancestry and nearly 100% of its Y-chromosomes by people with Steppe ancestry. We show that, in the Iron Age, Steppe ancestry had spread not only into Indo-European-speaking regions but also into non-Indo-European-speaking ones, and we reveal that present-day Basques are best described as a typical Iron Age population without the admixture events that later affected the rest of Iberia. Additionally, we document how, beginning at least in the Roman period, the ancestry of the peninsula was transformed by gene flow from North Africa and the eastern Mediterranean.

One of the most challenging points for ancient DNA studies on human remains is that analysing procedures involve partial or total destruction of the samples, which usually are unique and irreplaceable. This is what prevents museums, anthropologists or archaeologists from giving samples for genetic investigation. So that it is interesting to find an analysing method without destroying them. In this study, it was carried out the evaluation of a non-destructive extraction DNA protocol on 4 Neolithic individuals, from Can Gambús (Sabadell, Spain) and 4 pre Bell Beaker period individuals, from Los Cercados (Valladolid, Spain). Along this work, it was discussed the efficiency of the non-destructive protocol, valuing the obtained result, and the evidences state of preservation after the whole procedure.

The remains in the LTB tomb were not a traditional nuclear family (father, mother and son/daughter) and it was probably a tomb where two women, one of them pregnant, were buried.

Resumen Un elemento habitual en yacimientos prehistóricos como los del grupo arqueológico de Cogotas

Through this study we compared two DNA extraction methods for skeletal or dental human samples. For such\ud task there were analysed 38 samples from 19 individuals, selecting two samples from each one. When it was\ud possible, we selected dental complete samples, without cracks or cavities, and also with a natural light colour.\ud When there were no dental samples available, there were selected preferably skull or diaphysis of long bone.\ud The two samples from each individual were processed individually in two different laboratories (Laboratories\ud 1 and 2). There were employed a different DNA extraction methodology in each laboratory, applying in\ud Laboratory 1 the protocol proposed by Rohland and Hofreiter (2009), and in Laboratory 2 a commercial kit for\ud purification. Finally, in order to compare the efficiency of both methodologies, in Laboratory 2, aDNA quantification\ud by Real Time PCR (RTPCR) was performed, by the amplification of two different size mitochondrial DNA\ud fragments. In this way, it was possible to evaluate the efficiency of each protocol, and to discuss advantages and\ud disadvantages of each one