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Concept: Argentina


In 1985, a frozen mummy was found in Cerro Aconcagua (Argentina). Archaeological studies identified the mummy as a seven-year-old Inca sacrifice victim who lived >500 years ago, at the time of the expansion of the Inca Empire towards the southern cone. The sequence of its entire mitogenome was obtained. After querying a large worldwide database of mitogenomes (>28,000) we found that the Inca haplotype belonged to a branch of haplogroup C1b (C1bi) that has not yet been identified in modern Native Americans. The expansion of C1b into the Americas, as estimated using 203 C1b mitogenomes, dates to the initial Paleoindian settlements (~18.3 thousand years ago [kya]); however, its internal variation differs between Mesoamerica and South America. By querying large databases of control region haplotypes (>150,000), we found only a few C1bi members in Peru and Bolivia (e.g. Aymaras), including one haplotype retrieved from ancient DNA of an individual belonging to the Wari Empire (Peruvian Andes). Overall, the results suggest that the profile of the mummy represents a very rare sub-clade that arose 14.3 (5-23.6) kya and could have been more frequent in the past. A Peruvian Inca origin for present-day C1bi haplotypes would satisfy both the genetic and paleo-anthropological findings.

Concepts: South America, Americas, Argentina, Latin America, Chile, Andes, Peru, Inca Empire


Suicide affects people from different backgrounds, ethnical groups, socio-economic status and geographical locations. In Latin America, suicide reports arescarce, specially in Andean countries. In Ecuador, very few reports have partially described this phenomenon, nonetheless, estimation of the burden of disease (BoD) hasnever been reported in the country.

Concepts: United States, Sociology, Spanish language, Major depressive disorder, South America, Argentina, Chile, Human geography


Misiones, Argentina, contains the largest remaining tract of Upper Paraná Atlantic Forest ecoregion; however, ~50% of native forest is unprotected and located in a mosaic of plantations, agriculture, and pastures. Existing protected areas are becoming increasingly isolated due to ongoing habitat modification. These factors, combined with lower than expected regional carnivore densities, emphasize the need to understand the effect of fragmentation on animal movement and connectivity between protected areas. Using detection dogs and genetic analyses of scat, we collected data on jaguars (Panthera onca), pumas (Puma concolor), ocelots (Leopardus pardalis), oncillas (Leopardus tigrinus), and bush dogs (Speothos venaticus) across habitats that varied in vegetation, disturbance, human proximity, and protective status. With MaxEnt we evaluated habitat use, habitat suitability, and potential species richness for the five carnivores across northern-central Misiones, Argentina. Through a multifaceted cost analysis that included unique requirements of each carnivore and varying degrees of overlap among them, we determined the optimal location for primary/secondary corridors that would link the northern-central zones of the Green Corridor in Misiones and identified areas within these corridors needing priority management. A secondary analysis, comparing these multispecies corridors with the jaguar’s unique requirements, demonstrated that this multispecies approach balanced the preferences of all five species and effectively captured areas required by this highly restricted and endangered carnivore. We emphasize the potential importance of expanding beyond a single umbrella or focal species when developing biological corridors that aim to capture the varied ecological requirements of coexisting species and ecological processes across the landscape. Detection dogs and genetic analyses of scat allow data on multiple species to be collected efficiently across multiple habitat types independent of the degree of legal protection. These data used with multifocal GIS analyses balance the varying degree of overlap and unique properties among them allowing for comprehensive conservation strategies to be developed relatively rapidly. Our comprehensive approach serves as a model to other regions faced with habitat loss and lack of data. The five carnivores focused on in our study have wide ranges, so the results from this study can be expanded and combined with surrounding countries, with analyses at the species or community level.

Concepts: Brazil, Felidae, Argentina, Leopard, Jaguar, Ocelot, Leopardus, Felines


Examination of three frozen bodies, a 13-y-old girl and a girl and boy aged 4 to 5 y, separately entombed near the Andean summit of Volcán Llullaillaco, Argentina, sheds new light on human sacrifice as a central part of the Imperial Inca capacocha rite, described by chroniclers writing after the Spanish conquest. The high-resolution diachronic data presented here, obtained directly from scalp hair, implies escalating coca and alcohol ingestion in the lead-up to death. These data, combined with archaeological and radiological evidence, deepen our understanding of the circumstances and context of final placement on the mountain top. We argue that the individuals were treated differently according to their age, status, and ritual role. Finally, we relate our findings to questions of consent, coercion, and/or compliance, and the controversial issues of ideological justification and strategies of social control and political legitimation pursued by the expansionist Inca state before European contact.

Concepts: Bolivia, Argentina, Andes, Ecuador, Peru, Spanish Empire, Human sacrifice, Child sacrifice


The origins of the extinct Falkland Islands wolf (FIW), Dusicyon australis, have remained a mystery since it was first recorded by Europeans in the seventeenth century. It is the only terrestrial mammal on the Falkland Islands (also known as the Malvinas Islands), which lie ~460 km from Argentina, leading to suggestions of either human-mediated transport or overwater dispersal. Previous studies used ancient DNA from museum specimens to suggest that the FIW diverged from its closest living relative, the South American maned wolf (Chrysocyon brachyurus) around 7 Ma, and colonized the islands ~330 ka by unknown means. Here we retrieve ancient DNA from subfossils of an extinct mainland relative, Dusicyon avus, and reveal the FIW lineage became isolated only 16 ka (8-31 ka), during the last glacial phase. Submarine terraces, formed on the Argentine coastal shelf by low sea-stands during this period, suggest that the FIW colonized via a narrow, shallow marine strait, potentially while it was frozen over.

Concepts: Argentina, Falkland Islands, Maned Wolf, Falkland Islands Wolf, Falklands War, British overseas territories, South Georgia and the South Sandwich Islands, East Falkland


Baleen whales (Mysticeti) communicate using low-frequency acoustic signals. These long-wavelength sounds can be detected over hundreds of kilometres, potentially allowing contact over large distances. Low-frequency noise from large ships (20-200 Hz) overlaps acoustic signals used by baleen whales, and increased levels of underwater noise have been documented in areas with high shipping traffic. Reported responses of whales to increased noise include: habitat displacement, behavioural changes and alterations in the intensity, frequency and intervals of calls. However, it has been unclear whether exposure to noise results in physiological responses that may lead to significant consequences for individuals or populations. Here, we show that reduced ship traffic in the Bay of Fundy, Canada, following the events of 11 September 2001, resulted in a 6 dB decrease in underwater noise with a significant reduction below 150 Hz. This noise reduction was associated with decreased baseline levels of stress-related faecal hormone metabolites (glucocorticoids) in North Atlantic right whales (Eubalaena glacialis). This is the first evidence that exposure to low-frequency ship noise may be associated with chronic stress in whales, and has implications for all baleen whales in heavy ship traffic areas, and for recovery of this endangered right whale population.

Concepts: Atlantic Ocean, Sound, Argentina, Cetacea, Whale, Right whale, Baleen, Baleen whale


Given new distribution patterns of the endangered North Atlantic right whale (NARW; Eubalaena glacialis) population in recent years, an improved understanding of spatio-temporal movements are imperative for the conservation of this species. While so far visual data have provided most information on NARW movements, passive acoustic monitoring (PAM) was used in this study in order to better capture year-round NARW presence. This project used PAM data from 2004 to 2014 collected by 19 organizations throughout the western North Atlantic Ocean. Overall, data from 324 recorders (35,600 days) were processed and analyzed using a classification and detection system. Results highlight almost year-round habitat use of the western North Atlantic Ocean, with a decrease in detections in waters off Cape Hatteras, North Carolina in summer and fall. Data collected post 2010 showed an increased NARW presence in the mid-Atlantic region and a simultaneous decrease in the northern Gulf of Maine. In addition, NARWs were widely distributed across most regions throughout winter months. This study demonstrates that a large-scale analysis of PAM data provides significant value to understanding and tracking shifts in large whale movements over long time scales.

Concepts: United States, Atlantic Ocean, Baltic Sea, Argentina, Gulf of Mexico, Cetacea, Right whale, Cape Cod


The Chinook salmon Oncorhynchus tshawytscha, which was introduced deliberately in Chile four decades ago for sport fishing and aquaculture, represents a rare example of a successful translocation of an anadromous Pacific salmon into the southern Hemisphere, offering a unique opportunity to examine the role of introduction history and genetic variability in invasion success. We used historical information and mitochondrial displacement loop sequences (D-loop) from seven colonized sites in Chile and Argentina and from native and naturalized Chinook salmon populations to determine population sources and to examine levels of genetic diversity associated with the invasion. The analysis revealed that the Chinook salmon invasion in Patagonia originated from multiple population sources from northwestern North America and New Zealand, and admixed in the invaded range generating genetically diverse populations. Genetic analyses further indicated that the colonization of new populations ahead of the invasion front appear to have occurred by noncontiguous dispersal. Dispersal patterns coincided with ocean circulation patterns dominated by the West Wind Drift and the Cape Horn Currents. We conclude that admixture following multiple introductions, as well as long-distance dispersal events may have facilitated the successful invasion and rapid dispersal of Chinook salmon into Patagonia.

Concepts: DNA, Salmon, Chinook salmon, Oncorhynchus, Salmonidae, Pacific Ocean, Kamchatka Peninsula, Argentina


Eva Perón, best known as Evita, underwent a prefrontal lobotomy in 1952. Although the procedure was said to have been performed to relieve the pain of metastatic cancer, the author carried out a search for evidence that suggests that the procedure was prescribed to decrease violence and to modify Evita’s behavior and personality, and not just for pain control. To further elucidate the circumstances surrounding the treatment of this well-known historic figure, the author reviewed the development of the procedure known as prefrontal lobotomy and its three main indications: management of psychiatric illness, control of intractable pain from terminal cancer, and mind control and behavior/personality modification. The role of pioneering neurosurgeons in the development of prefrontal lobotomy, particularly in Connecticut and at Yale University, was also studied, and the political and historical conditions in Argentina in 1952 and to the present were analyzed. Evita was the wife of Juan Perón, who was the supreme leader of the Peronist party as well as president of Argentina. In 1952, however, the Peronist government in Argentina was bicephalic because Evita led the left wing of the party and ran the Female Peronist Party and the Eva Perón Foundation. She was followed by a group of hardcore loyalists interested in accelerating the revolution. Evita was also suffering from metastatic cervical cancer, and her illness increased her anxiety and moved her to purchase weapons to start training workers' militias. Although the apparent purpose was to fight her husband’s enemies, this was done without his knowledge. She delivered fiery political speeches and wrote incendiary documents that would have led to a fierce clash in the country at that time. Notwithstanding the disreputable connotation of conspiracy theories, evidence was found of a potentially sinister political conspiracy, led by General Perón, to quiet down his wife Evita and modify her behavior/personality to decrease her belligerence, in addition to treating her cancer-related pain. Psychosurgery was purportedly intended to calm Evita and thus avoid a bloody civil war in Argentina. It was carried out in maximum secrecy and involved a distinguished American neurosurgeon, Dr. James L. Poppen, from the Lahey Clinic in Boston. A recorded and videotaped interview with a former scrub nurse and confidante of Dr. James L. Poppen revealed that prior to the lobotomy on Eva Perón, he performed lobotomies on a few prisoners in the prison system in Buenos Aires. Later, Dr. Poppen seems to have regretted his involvement and participation in this sad chapter in Argentine history. The treatment of Evita at the end of her life was influenced by extraordinary circumstances of time and place but also involved general issues of medical professionalism, the ethics of neuroscience, and the risks of being manipulated by labyrinthine byzantine politics. This story serves as a reminder that any physician, even one considered to be one of the best in the world, may act naively and become a pawn in a game he cannot begin to fathom.

Concepts: Cancer, Metastasis, Neurosurgery, Argentina, Buenos Aires, Eva Perón, Lobotomy, Juan Perón


BACKGROUND: Melanocytic nevi are frequently found on acral volar skin. Differentiation between nevi and melanoma is essential and sometimes difficult, although dermoscopy has enabled a more specific diagnosis of pigmented lesions. Dermoscopic patterns of lesions on acral volar skin have mostly been described in European and Asian populations. The Latin American population is heterogeneous, and particularly so in the case of Uruguayans, who largely descend from 3 distinct populations. OBJECTIVE: To describe dermoscopic patterns of acral melanocytic nevi and evaluate their applicability in a Latin American population in Uruguay. PATIENTS AND METHODS: This was an observational, descriptive, cross-sectional study conducted by 2 dermatologists from 4 dermatology clinics in Uruguay. Uruguayan patients older than 18 years with acral melanocytic nevi were included. Digital dermoscopic images were captured and jointly analyzed by 2 investigators. RESULTS: A total of 158 acral volar nevi in 80 patients were analyzed. The most-prevalent pattern was the parallel furrow pattern (51.3% of nevi), followed by the latticelike pattern (13.3%), the homogeneous pattern (12.7%), the globular pattern (9.5%), the fibrillar pattern (7%), the globulostreaklike pattern (3.8%), and the nontypical pattern (2.5%). The reticular and transition patterns were not observed in our population. CONCLUSIONS: The parallel furrow pattern, followed by the latticelike and homogeneous patterns, was the most-prevalent pattern in acral melanocytic nevi in the Uruguayan population. The fibrillar pattern was found exclusively on the soles. No new dermoscopic patterns were observed. The patterns described in Asian and European literature apply to our population.

Concepts: Melanoma, Spanish language, Europe, Italian language, Argentina, Latin America, Dysplastic nevus, Uruguay