A pattern of population crash and rapid recovery is a common feature of the pacification and settlement experience of the indigenous peoples of tropical South America. Despite the obvious importance of these events to the demographic and anthropological sciences as a whole, as well as their significant practical implications, little is known about the microdemographic determinants of these paired phenomena. Using methods of asymptotic and stochastic demographic analysis, we reconstructed the microdemographic drivers of this history among one indigenous population: the Northern Aché of eastern Paraguay. This article explores the implications of these relationships for understanding the overall demographic turnaround observed within similar groups, as well as for the future trajectory of the Northern Aché in particular.

Ancient (proto-) Bulgarians have long been thought of as a Turkic population. However, evidence found in the past three decades shows that this is not the case. Until now, this evidence has not included ancient mitochondrial DNA (mtDNA) analysis. To fill this void, we collected human remains from the 8th to the 10th century AD located in three necropolises in Bulgaria: Nojarevo (Silistra region) and Monastery of Mostich (Shumen region), both in northeastern Bulgaria, and Tuhovishte (Satovcha region) in southwestern Bulgaria. The phylogenetic analysis of 13 ancient DNA samples (extracted from teeth) identified 12 independent haplotypes, which we further classified into mtDNA haplogroups found in present-day European and western Eurasian populations. Our results suggest a western Eurasian matrilineal origin for proto-Bulgarians, as well as a genetic similarity between proto- and modern Bulgarians. Our future work will provide additional data that will further clarify proto-Bulgarian origins, thereby adding new clues to the current understanding of European genetic evolution.

Recent studies have expanded and refined the founding haplogroups of the Americas using whole mitochondrial (mtDNA) genome analysis. In addition to pan-American lineages, specific variants have been identified in a number of studies that show higher frequencies in restricted geographical areas. To further characterize Native American maternal lineages and specifically examine local patterns within South America, we analyzed 12 maternally unrelated Yekuana whole mtDNA genomes from one village (Sharamaña) that include the four major Native American haplogroups A2, B2, C1, and D1. Based on our results, we propose a reconfiguration of one subhaplogroup A2 (A2aa) that is specific to South America and identify other singleton branches across the four haplogroups. Furthermore, we show nucleotide diversity values that increase from north to south for haplogroups C1 and D1. The results from our work add to the growing mitogenomic data that highlight local phylogenies and support the rapid genetic differentiation of South American populations, which has been correlated with the linguistic diversity in the region by previous studies.

Hereditary hemochromatosis is caused by a potentially lethal recessive gene (HFE, C282Y allele) that increases iron absorption and reaches polymorphic levels in northern European populations. Because persons carrying the allele absorb iron more readily than do noncarriers, it has often been suggested that HFE is an adaptation to anemia. We hypothesize positive selection for HFE began during or after the European Neolithic with the adoption of an iron-deficient high-grain and dairying diet and consequent anemia, a finding confirmed in Neolithic and later European skeletons. HFE frequency compared with rate of lactase persistence in Eurasia yields a positive linear correlation coefficient of 0.86. We suggest this is just one of many mutations that became common after the adoption of agriculture.

The genetic basis of androstenone anosmia has been well studied due to androstenone's putative role as a human sex pheromone and its presence in pork meat. Polymorphisms have been identified on the olfactory receptor gene OR7D4, which significantly affect perception of androstenone pleasantness and intensity in several Western populations. This study aims to investigate androstenone sensitivity and the influence of OR7D4 polymorphisms in non-Western populations. Androstenone perception was tested in 132 individuals from Madagascar using a double three-alternative choice test with two concentrations of androstenone (0.17 and 1.7 µg/ml). We found that Malagasy populations described this molecule in a similar way to European populations, and 21% of the sample was not able to smell androstenone. In contrast to previous studies, there was no significant evidence of the influence of rs61729907: C>T (R88W) and rs5020278: C>T polymorphisms (T133M) on androstenone sensitivity in Malagasy populations. We found, however, a significant effect of the polymorphism rs61732668 (P79L) and a significant difference in androstenone perception between populations in different locations across Madagascar. This study indicates the existence of population-specific factors in androstenone sensitivity, suggesting that population history has a role in shaping an individual's smell and flavor preferences and food preferences in general.

To gain insight into the social organization of a population associated with the Dawenkou period, we performed ancient DNA analysis of 18 individuals from human remains from the Fujia site in Shandong Province, China. Directly radiocarbon dated to 4800–4500 cal BP, the Fujia site is assumed to be associated with a transitional phase from matrilineal clans to patrilineal monogamous families. Our results reveal a low mitochondrial DNA diversity from the site and population. Combined with Y chromosome data, the pattern observed at the Fujia site is most consistent with a matrilineal community. The patterns also suggest that the bond of marriage was de-emphasized compared with the bonds of descent at Fujia.