Genetic legacy of state centralization in the Kuba Kingdom of the Democratic Republic of the Congo.

Few phenomena have had as profound or long-lasting consequences in human history as the emergence of large-scale centralized states in the place of smaller scale and more local societies. This study examines a fundamental, and yet unexplored, consequence of state formation: its genetic legacy. We studied the genetic impact of state centralization during the formation of the eminent precolonial Kuba Kingdom of the Democratic Republic of the Congo (DRC) in the 17th century. We analyzed genome-wide data from over 690 individuals sampled from 27 different ethnic groups from the Kasai Central Province of the DRC. By comparing genetic patterns in the present-day Kuba, whose ancestors were part of the Kuba Kingdom, with those in neighboring non-Kuba groups, we show that the Kuba today are more genetically diverse and more similar to other groups in the region than expected, consistent with the historical unification of distinct subgroups during state centralization. We also found evidence of genetic mixing dating to the time of the Kingdom at its most prominent. Using this unique dataset, we characterize the genetic history of the Kasai Central Province and describe the historic late wave of migrations into the region that contributed to a Bantu-like ancestry component found across large parts of Africa today. Taken together, we show the power of genetics to evidence events of sociopolitical importance and highlight how DNA can be used to better understand the behaviors of both people and institutions in the past.

Moralizing gods, impartiality and religious parochialism across 15 societies.

The emergence of large-scale cooperation during the Holocene remains a central problem in the evolutionary literature. One hypothesis points to culturally evolved beliefs in punishing, interventionist gods that facilitate the extension of cooperative behaviour toward geographically distant co-religionists. Furthermore, another hypothesis points to such mechanisms being constrained to the religious ingroup, possibly at the expense of religious outgroups. To test these hypotheses, we administered two behavioural experiments and a set of interviews to a sample of 2228 participants from 15 diverse populations. These populations included foragers, pastoralists, horticulturalists, and wage labourers, practicing Buddhism, Christianity, and Hinduism, but also forms of animism and ancestor worship. Using the Random Allocation Game (RAG) and the Dictator Game (DG) in which individuals allocated money between themselves, local and geographically distant co-religionists, and religious outgroups, we found that higher ratings of gods as monitoring and punishing predicted decreased local favouritism (RAGs) and increased resource-sharing with distant co-religionists (DGs). The effects of punishing and monitoring gods on outgroup allocations revealed between-site variability, suggesting that in the absence of intergroup hostility, moralizing gods may be implicated in cooperative behaviour toward outgroups. These results provide support for the hypothesis that beliefs in monitoring and punitive gods help expand the circle of sustainable social interaction, and open questions about the treatment of religious outgroups.

Using a Microsurgical Robotic Platform for In-flap Anastomosis in Autologous Bipedicular Breast Reconstruction.

Autologous microsurgical breast reconstruction has become a standard of care. As techniques become more individualized and aim for less-invasive approaches, vessels ever smaller in diameter are considered for flap anastomosis. Robot-assisted surgery has great potential to reduce tremor and enhance precise motion. The Symani Surgical System (Medical Microinstruments, Inc., Wilmington, Del.) is a robotic platform designed for microsurgery. It was used for a microsurgical in-flap anastomosis of a bipedicular deep inferior epigastric artery flap for unilateral breast reconstruction. The procedure included fully robot-assisted anastomoses with significant size mismatches using a 3D-exoscope for magnification. Arterial and venous anastomoses were entirely robot-assisted completed in 23 minutes (seven stitches) and 28 minutes (eight stitches) using 9/0 nylon sutures. The intra- and postoperative course was uneventful. This robotic platform facilitates in-flap anastomoses of small vessels by increasing the precision of instrument handling and eliminating tremor. The combination of robotic platforms and exoscopes provides superior ergonomics in comparison with conventional (super)microsurgery. We expect robotic platforms to play a significant role in modern microsurgical breast reconstruction.