Mosaic maternal ancestry in the Great Lakes region of East Africa

The Great Lakes lie within a region of East Africa with very high human genetic diversity, home of many ethno-linguistic groups usually assumed to be the product of a small number of major dispersals. However, our knowledge of these dispersals relies primarily on the inferences of historical, linguistics and oral traditions, with attempts to match up the archaeological evidence where possible. This is an obvious area to which archaeogenetics can contribute, yet Uganda, at the heart of these developments, has not been studied for mitochondrial DNA (mtDNA) variation. Here, we compare mtDNA lineages at this putative genetic crossroads across 409 representatives of the major language groups: Bantu speakers and Eastern and Western Nilotic speakers. We show that Uganda harbours one of the highest mtDNA diversities within and between linguistic groups, with the various groups significantly differentiated from each other. Despite an inferred linguistic origin in South Sudan, the data from the two Nilotic-speaking groups point to a much more complex history, involving not only possible dispersals from Sudan and the Horn but also large-scale assimilation of autochthonous lineages within East Africa and even Uganda itself. The Eastern Nilotic group also carries signals characteristic of West-Central Africa, primarily due to Bantu influence, whereas a much stronger signal in the Western Nilotic group suggests direct West-Central African ancestry. Bantu speakers share lineages with both Nilotic groups, and also harbour East African lineages not found in Western Nilotic speakers, likely due to assimilating indigenous populations since arriving in the region ~3000 years ago.

Resolving the ancestry of Austronesian‑speaking populations

There are two very different interpretations of the prehistory of Island Southeast Asia (ISEA), with genetic evidence invoked in support of both. The "out-of-Taiwan" model proposes a major Late Holocene expansion of Neolithic Austronesian speakers from Taiwan. An alternative, proposing that Late Glacial/postglacial sea-level rises triggered largely autochthonous dispersals, accounts for some otherwise enigmatic genetic patterns, but fails to explain the Austronesian language dispersal. Combining mitochondrial DNA (mtDNA), Y-chromosome and genome-wide data, we performed the most comprehensive analysis of the region to date, obtaining highly consistent results across all three systems and allowing us to reconcile the models. We infer a primarily common ancestry for Taiwan/ISEA populations established before the Neolithic, but also detected clear signals of two minor Late Holocene migrations, probably representing Neolithic input from both Mainland Southeast Asia and South China, via Taiwan. This latter may therefore have mediated the Austronesian language dispersal, implying small-scale migration and language shift rather than large-scale expansion.

O corpo extremo (sobre 'A Morte sem Mestre' de Herberto Helder)

Observada pelo ângulo da continuidade com que desde sempre o texto herbertiano se deu a ler, A Morte sem Mestre corresponde, à partida, a um ponto extremo: o da forçada interrupção de um corpo pela brutal emergência do fim, a liquidação da sua biologia. O livro, ele mesmo, constitui como tal um lugar-limite que acolhe um pensamento-limite e sobre o limite, lugar e pensamento que tendem assim a um inevitável fora de cena, a um radical impudor que é também afirmação de um impoder. Se o lermos sobre o traço do tempo, como aqui nos propomos fazer, na extremidade 'ad quem' do itinerário orgânico da escrita herbertiana, como etapa seguinte de um trajeto de irrevogável corrupção e ruína, provavelmente - e num sentido estritamente demoníaco-, A Morte sem Mestre não poderia deixar de ser o que é: mais do que esse objeto estranho que chocou a crítica, um objeto desastroso, 'exemplum' perfeitamente imperfeito de uma espécie de corpo-desastre que se apresenta como postergação (calculada?) do fulgor poético, assumindo essa «tarefa prostitucional da poesia» que legitimamente lhe apontou António Guerreiro (2014), colocando-a sob a presumível égide de Sade ou de Bataille.