Journal articles: 'Andean populations'

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Yasukochi, Yoshiki, Takayuki Nishimura, Juan Ugarte, Mayumi Ohnishi, Mika Nishihara, Guillermo Alvarez, Hideki Fukuda, Victor Mendoza, and Kiyoshi Aoyagi. "Effect of EGLN1 Genetic Polymorphisms on Hemoglobin Concentration in Andean Highlanders." BioMed Research International 2020 (November 15, 2020): 1–16. http://dx.doi.org/10.1155/2020/3436581.

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The physiological characteristics of Andean natives living at high altitudes have been investigated extensively, with many studies reporting that Andean highlanders have a higher hemoglobin (Hb) concentration than other highlander populations. It has previously been reported that positive natural selection has acted independently on the egl-9 family hypoxia inducible factor 1 (EGLN1) gene in Tibetan and Andean highlanders and is related to Hb concentration in Tibetans. However, no study has yet revealed the genetic determinants of Hb concentration in Andeans even though several single-nucleotide polymorphisms (SNPs) in EGLN1 have previously been examined. Therefore, we explored the relationship between hematological measurements and tag SNPs designed to cover the whole EGLN1 genomic region in Andean highlanders living in Bolivia. Our findings indicated that haplotype frequencies estimated from the EGLN1 SNPs were significantly correlated with Hb concentration in the Bolivian highlanders. Moreover, we found that an Andean-dominant haplotype related to high Hb level may have expanded rapidly in ancestral Andean highlander populations. Analysis of genotype data in an ~436.3 kb genomic region containing EGLN1 using public databases indicated that the population structure based on EGLN1 genetic markers in Andean highlanders was largely different from that in other human populations. This finding may be related to an intrinsic or adaptive physiological characteristic of Andean highlanders. In conclusion, the high Hb concentrations in Andean highlanders can be partly characterized by EGLN1 genetic variants.

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Chirinos, Diana A., Oscar L. Morey-Vargas, Ronald B. Goldberg, Julio A. Chirinos, and Josefina Medina-Lezama. "Metabolic Syndrome in Andean Populations." Global Heart 8, no. 4 (December 1, 2013): 349. http://dx.doi.org/10.1016/j.gheart.2013.10.001.

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Vargas, Marco, Enrique Vargas, Colleen G. Julian, J. Fernando Armaza, Armando Rodriguez, Wilma Tellez, Susan Niermeyer, et al. "Determinants of blood oxygenation during pregnancy in Andean and European residents of high altitude." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 293, no. 3 (September 2007): R1303—R1312. http://dx.doi.org/10.1152/ajpregu.00805.2006.

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High altitude decreases birth weight, but this effect is diminished in long vs. short-resident, high-altitude populations. We asked whether women from long vs. short-resident, high-altitude populations had higher arterial oxygenation levels by comparing 42 Andean and 26 European residents of La Paz, Bolivia (3,600 m), serially during pregnancy ( weeks 20, 30, and 36) and again 4 mo postpartum. Pregnancy raised hypoxic ventilatory sensitivity threefold, resting ventilation (V̇e), and arterial O2saturation (SaO2) in both groups. Ancestry, as identified using 81 genetic markers, correlated with respiratory pattern, such that greater Andean ancestry was associated with higher respiratory frequency and lower tidal volume. Pregnancy increased total blood and plasma volume ∼40% in both groups without changing red blood cell mass relative to body weight; hence, hemoglobin fell. The hemoglobin decline was compensated for by the rise in V̇e and SaO2with the result that arterial O2content (CaO2) was maintained near nonpregnant levels in both groups. Birth weights were similar for all Andean and European babies, but after adjusting for variation in gestational age, maternal height and parity, Andeans weighed 209 g more than Europeans. Babies with heavier birth weights and greater ponderal indices were born to Andean women with higher V̇e during pregnancy. We concluded that while maternal V̇e and arterial oxygenation were important, some factor other than higher CaO2was responsible for protecting Andeans from altitude-associated reductions in fetal growth.

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Jansen, Gerard FA, and Buddha Basnyat. "Brain Blood Flow in Andean and Himalayan High-Altitude Populations: Evidence of Different Traits for the Same Environmental Constraint." Journal of Cerebral Blood Flow & Metabolism 31, no. 2 (August 25, 2010): 706–14. http://dx.doi.org/10.1038/jcbfm.2010.150.

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Humans have populated the Tibetan plateau much longer than the Andean Altiplano. It is thought that the difference in length of occupation of these altitudes has led to different responses to the stress of hypoxia. As such, Andean populations have higher hematocrit levels than Himalayans. In contrast, Himalayans have increased circulation to certain organ systems to meet tissue oxygen demand. In this study, we hypothesize that cerebral blood flow ( CBF) is higher in Himalayans than in Andeans. Using a MEDLINE and EMBASE search, we included 10 studies that investigated CBF in Andeans and Himalayans between 3,658 and 4,330 m altitude. The CBF values were corrected for differences in hematocrit and arterial oxygen saturation. The data of these studies show a mean hematocrit of 50% in Himalayans and 54.1% in Andeans. Arterial oxygen saturation was 86.9% in Andeans and 88.4% in Himalayans. The CBF in Himalayans was slightly elevated compared with sea-level subjects, and was 24% higher compared with Andeans. After correction for hematorit and arterial oxygen saturation, CBF was ~20% higher in Himalayans compared with Andeans. Altered brain metabolism in Andeans, and/or increased nitric oxide availability in Himalayans may have a role to explain this difference in brain blood flow.

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Mairbäurl, Heimo, Max Gassmann, and Martina U. Muckenthaler. "Geographical ancestry affects normal hemoglobin values in high-altitude residents." Journal of Applied Physiology 129, no. 6 (December 1, 2020): 1451–59. http://dx.doi.org/10.1152/japplphysiol.00025.2020.

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Increasing the hemoglobin (Hb) concentration is a major mechanism adjusting arterial oxygen content to decreased oxygen partial pressure of inspired air at high altitude. Approximately 5% of the world’s population living at altitudes higher than 1,500 m shows this adaptive mechanism. Notably, there is a wide variation in the extent of increase in Hb concentration among different populations. This short review summarizes available information on Hb concentrations of high-altitude residents living at comparable altitudes (3,500–4,500 m) in different regions of the world. An increased Hb concentration is found in all high-altitude populations. The highest mean Hb concentration was found in adult male Andean residents and in Han Chinese living at high altitude, whereas it was lowest in Ethiopians, Tibetans, and Sherpas. A lower plasma volume in Andean high-altitude natives may offer a partial explanation. Indeed, male Andean high-altitude natives have a lower plasma volume than Tibetans and Ethiopians. Moreover, Hb values were lower in adult, nonpregnant females than in males; differences between populations of different ancestry were less pronounced. Various genetic polymorphisms were detected in high-altitude residents thought to favor life in a hypoxic environment, some of which correlate with the relatively low Hb concentration in the Tibetans and Ethiopians, whereas differences in angiotensin-converting enzyme allele distribution may be related to elevated Hb in the Andeans. Taken together, these results indicate different sensitivity of oxygen dependent control of erythropoiesis or plasma volume among populations of different geographical ancestry, offering explanations for differences in the Hb concentration at high altitude.

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Julian, Colleen Glyde, Megan J. Wilson, Miriam Lopez, Henry Yamashiro, Wilma Tellez, Armando Rodriguez, Abigail W. Bigham, et al. "Augmented uterine artery blood flow and oxygen delivery protect Andeans from altitude-associated reductions in fetal growth." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 296, no. 5 (May 2009): R1564—R1575. http://dx.doi.org/10.1152/ajpregu.90945.2008.

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The effect of high altitude on reducing birth weight is markedly less in populations of high- (e.g., Andeans) relative to low-altitude origin (e.g., Europeans). Uterine artery (UA) blood flow is greater during pregnancy in Andeans than Europeans at high altitude; however, it is not clear whether such blood flow differences play a causal role in ancestry-associated variations in fetal growth. We tested the hypothesis that greater UA blood flow contributes to the protection of fetal growth afforded by Andean ancestry by comparing UA blood flow and fetal growth throughout pregnancy in 137 Andean or European residents of low (400 m; European n = 28, Andean n = 23) or high (3,100–4,100 m; European n = 51, Andean n = 35) altitude in Bolivia. Blood flow and fetal biometry were assessed by Doppler ultrasound, and maternal ancestry was confirmed, using a panel of 100 ancestry-informative genetic markers (AIMs). At low altitude, there were no ancestry-related differences in the pregnancy-associated rise in UA blood flow, fetal biometry, or birth weight. At high altitude, Andean infants weighed 253 g more than European infants after controlling for gestational age and other known influences. UA blood flow and O2delivery were twofold greater at 20 wk in Andean than European women at high altitude, and were paralleled by greater fetal size. Moreover, variation in the proportion of Indigenous American ancestry among individual women was positively associated with UA diameter, blood flow, O2delivery, and fetal head circumference. We concluded that greater UA blood flow protects against hypoxia-associated reductions in fetal growth, consistent with the hypothesis that genetic factors enabled Andeans to achieve a greater pregnancy-associated rise in UA blood flow and O2delivery than European women at high altitude.

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Wilson, Megan J., Miriam Lopez, Marco Vargas, Colleen Julian, Wilma Tellez, Armando Rodriguez, Abigail Bigham, et al. "Greater uterine artery blood flow during pregnancy in multigenerational (Andean) than shorter-term (European) high-altitude residents." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 293, no. 3 (September 2007): R1313—R1324. http://dx.doi.org/10.1152/ajpregu.00806.2006.

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Multigenerational (Andean) compared with shorter-term (European) high-altitude residents exhibit less hypoxia-associated reductions in birth weight. Because differences in arterial O2content are not responsible, we asked whether greater pregnancy-associated increases in uterine artery (UA) blood flow and O2delivery were involved. Serial studies were conducted in 42 Andean and 26 European residents of La Paz, Bolivia (3600 m) at weeks 20, 30, 36 of pregnancy and 4 mo postpartum using Doppler ultrasound. There were no differences postpartum but Andean vs. European women had greater UA diameter (0.65 ± 0.01 vs. 0.56 ± 0.01 cm), cross-sectional area (33.1 ± 0.97 vs. 24.7 ± 1.18 mm2), and blood flow at week 36 (743 ± 87 vs. 474 ± 36 ml/min) (all P < 0.05) and thus 1.6-fold greater uteroplacental O2delivery near term (126.82 ± 18.47 vs. 80.33 ± 8.69 ml O2·ml blood−1·min−1, P < 0.05). Andeans had greater common iliac (CI) flow and lower external iliac relative to CI flow (0.52 ± 0.11 vs. 0.95 ± 0.14, P < 0.05) than Europeans at week 36. After adjusting for gestational age, maternal height, and parity, Andean babies weighed 209 g more than the Europeans. Greater UA cross-sectional area at week 30 related positively to birth weight in Andeans ( r = +0.39) but negatively in Europeans ( r = −0.37) (both P < 0.01). We concluded that a greater pregnancy-associated increase in UA diameter raised UA blood flow and uteroplacental O2delivery in the Andeans and contributed to their ability to maintain normal fetal growth under conditions of high-altitude hypoxia. These data implicate the involvement of genetic factors in protecting multigenerational populations from hypoxia-associated reductions in fetal growth, but future studies are required for confirmation and identification of the specific genes involved.

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Skroch, Paul, Jim Nienhuis, Geunwha Jung, and Dermot Coyne. "Integration of RAPD Marker Genetic Linkage Maps in Phaseolus vulgaris L." HortScience 30, no. 4 (July 1995): 772D—772. http://dx.doi.org/10.21273/hortsci.30.4.772d.

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Currently, we are studying the genetics and linkage relationships of important quantitative and qualitative traits in common bean, including disease resistances, plant architecture, seed size and shape, and pod size, shape, and fiber content. Study of the genetics of these traits is being facilitated through the use of RAPD marker-based linkage maps in four RI populations. Cultivated P.vulgaris has two primary centers of diversity—Meso-american and Andean, the RI populations used for mapping are Meso x Andean (Bat93 x Jalo EEP558 and Eagle x Puebla 152), Andean x Andean (PC50 x Xan159), and Meso x Meso (BAC6 x HT7719) crosses. Maps in these four populations are being integrated through the use of cosegregating markers. Integration of maps will allow integration of the linkage relationships of relevant genes and also allow more efficient sampling of markers for future linkage studies.

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Skroth, Paul, Jim Nienhuis, Geunhwa Jung, and Dermont Coyne. "461 PB 292 MAPPING RAPD MARKER DIVERSITY IN PHASEOLUS VULGARIS." HortScience 29, no. 5 (May 1994): 497c—497. http://dx.doi.org/10.21273/hortsci.29.5.497c.

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Knowledge of genetic relationships and genetic diversity among accessions is essential for the efficient construction, maintainance and utilization of large ex-situ germplasm collections. Furthermore, streamlining of large collections into care collections necessitates validation of germplasm sampling techniques. DNA molecular markers provide potentially unbiased estimators of genome diversity end may facilitate organization, maintainance, and sampling of plant genetic resources. Our data suggests that RAPD markers will be o good tool for testing tore collection concepts and organizing genetic diversity in common bean. However, the genomic distribution of markers is unknown. Currently we are using recombinant inbred (RI) populations to place RAPD markers in the context of the bean genetic map. We hove evaluated the the distribution of RAPD markers in three RI populations: Bat93 × Jalo EEP558, PC50 × Xan159, and BAC6 × HT7719. Cultivated P.vulgaris has two primary renters of diversity Mesoamerican and Andean, the RI populations used for mapping RAPD markers ore Meso × Andean, Andean × Andean, and Meso × Meso crosses respectively. In the Bat93 × Jalo EEP558 population 383 markers have been mapped for a map length of 735 cM. However, approximately 150 of these markers ore members of 9 dusters which span only 90 cM. This inter gone pool mop is being integrated with linkage mops constructed in the other two populations to compare within and between gene pool marker distributions and to evaluate clustering of markers on the different mops. Implications for the application of RAPD markers will be discussed.

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Nienhuis, James, Paul Skroch, and Steve Beebe. "Comparison of Genetic Diversity between Nuña and and Other Andean bean (Phaseolus vulgaris) Populations." HortScience 32, no. 3 (June 1997): 544C—544. http://dx.doi.org/10.21273/hortsci.32.3.544c.

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Nuñas are a type of common bean (Phaseolus vulgaris) that possess the unusual characteristic of popping or expanding their cotyledonary tissue when heated. Numerous landraces of nuña beans were domesticated in the Andean region of South America (Peru, Bolivia, and Ecuador) and have been grown and consumed in this region since antiquity. The practical consideration in the domestication of nuñas in the high Andes was likely due to the greater energy efficiency in cooking toasted vs. boiled seeds.The Phaseolus germplasm bank at CIAT (Centro Internacional de Agricultura Tropical) has developed a core collection of Andean beans that includes numerous nuña landraces. Based on the wide range of phaseolin types observed among nuña landraces, it has been hypothesized that nuñas may represent a greater source of genetic diversity compared to other landraces and cultivars of common bean. Eighty nuña accessions and 120 nonpopping common bean accessions were randomly sampled from the CIAT Andean germplasm core collection. The 200 accessions were characterized for 140 mapped RAPD markers. The objectives of our research were to 1) understand the genetic structure of nuña bean accessions relative to other Andean common beans, and 2) to measure the genetic distance and genetic diversity between nuña and other Andean bean populations.

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Rothhammer, Francisco, Elena Llop, Pilar Carvallo, and Mauricio Moraga. "Origin and Evolutionary Relationships of Native Andean Populations." High Altitude Medicine & Biology 2, no. 2 (June 2001): 227–33. http://dx.doi.org/10.1089/152702901750265323.

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Postigo, Julio C. "Perception and Resilience of Andean Populations Facing Climate Change." Journal of Ethnobiology 34, no. 3 (October 2014): 383–400. http://dx.doi.org/10.2993/0278-0771-34.3.383.

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Vilaseca, Carolina, Marco A. Méndez, Carlos F. Pinto, and Hugo A. Benítez. "Assessment of Shape Variation Patterns in Triatoma infestans (Klug 1834) (Hemiptera: Reduviidae: Triatominae): A First Report in Populations from Bolivia." Insects 11, no. 5 (April 30, 2020): 274. http://dx.doi.org/10.3390/insects11050274.

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The morphological variations of four populations of geographically isolated Triatoma infestans located in the area of inter-Andean valleys and Chaco of Chuquisaca, Bolivia, were evaluated. Fifty-three females and sixty-one males were collected in the peri-domicile and analyzed with geometric morphometrics tools to study the patterns of the head and wing shape variation. The principal component analysis and canonical variate analysis revealed morphological variations between the populations studied, which were then confirmed by the permutation test of the differences between populations using Mahalanobis and Procustes distances. The multivariate regression analysis shows that the centroid size influences the shape of the heads and wings. T. infestans of the inter-Andean valleys are longer in the head and wings compared to the population of the Chaco. We propose that the geometric shape variation may be explained by geographical changes in climatic conditions, peri-domiciliar habitats, food source quality, and the use of insecticides.

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Rodríguez, Daniel, Adriana Reyes, Andres Quiñones-Guerrero, Fidel Ernesto Poveda-Gómez, Yeimy Castillo-Navarro, Robinson Duque, and Nicolás Rafael Reyes-Amaya. "Andean bear (Tremarctos ornatus) population density and relative abundance at the buffer zone of the Chingaza National Natural Park, cordillera oriental of the colombian andes." Papéis Avulsos de Zoologia 60 (July 16, 2020): e20206030. http://dx.doi.org/10.11606/1807-0205/2020.60.30.

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The Andean bear (Tremarctos ornatus) population density and relative abundance within the Chingaza Massif were assessed between September 2015 and May 2016. One hundred seventeen (117) camera traps were installed at 9 grids: 13 cameras per grid, each camera separated 750 m from the other; the sampling effort was 17,057 days-trap. Two thousand seven hundred eighty-four (2,784) native fauna records were obtained, 1,456 corresponding to mammals, 183 records for Andean bear specimens, 158 of them independent bear records (at least one hour between records), and 106 effective-independent bear records (also permitting individual recognition). Fifty-seven (57) Andean bear individuals were identified according to key external morphological features. Sixteen (16) adults were recaptured (12 males and 4 females), with a maximum mean distance of 27.22 km. Bears population density was 2.9 bears per 100 km². Based on this density and the buffer area of the sampling grids, we estimated an overall number of 122 bears in 4,215.15 km². The estimated density is the first for the species in Colombia and the lowest regarding previous reports from other countries. Thus, it is necessary to better understand how integral habitat quality and the anthropic impacts on habitat quality, availability, and connectivity may affect the Andean bear population densities in Colombia, as a useful tool for assessing populations` state and focus future conservation actions.

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Velez-Espino, L. A. "Population viability and perturbation analyses in remnant populations of the Andean catfish Astroblepus ubidiai." Ecology of Freshwater Fish 14, no. 2 (June 2005): 125–38. http://dx.doi.org/10.1111/j.1600-0633.2005.00084.x.

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Eichstaedt, Christina A., Tiago Antao, Alexia Cardona, Luca Pagani, Toomas Kivisild, and Maru Mormina. "Positive selection of AS3MT to arsenic water in Andean populations." Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis 780 (October 2015): 97–102. http://dx.doi.org/10.1016/j.mrfmmm.2015.07.007.

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Vega-Polo, Pamela, Maria Mercedes Cobo, Andrea Argudo, Bernardo Gutierrez, Jennifer Rowntree, and Maria de Lourdes Torres. "Characterizing the genetic diversity of the Andean blueberry (Vaccinium floribundum Kunth.) across the Ecuadorian Highlands." PLOS ONE 15, no. 12 (December 7, 2020): e0243420. http://dx.doi.org/10.1371/journal.pone.0243420.

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The Ecuadorian páramo, a high altitude tundra-like ecosystem, is a unique source of various ecosystem services and distinct biodiversity. Anthropogenic activities are associated with its fragmentation, which alters ecological factors and directly threatens resident species. Vaccinium floribundum Kunth., commonly known as Andean blueberry or mortiño, is a wild shrub endemic to the Andean region and highly valued in Ecuador for its berries, which are widely used in food preparations and hold an important cultural value. Since it is a wild species, mortiño could be vulnerable to environmental changes, resulting in a reduction of the size and distribution of its populations. To evaluate the extent of these effects on the mortiño populations, we assessed the genetic diversity and population structure of the species along the Ecuadorian highlands. We designed and developed a set of 30 species-specific SSR (simple sequence repeats) markers and used 16 of these to characterize 100 mortiño individuals from 27 collection sites. Our results revealed a high degree of genetic diversity (HE = 0.73) for the Ecuadorian mortiño, and a population structure analyses suggested the existence of distinct genetic clusters present in the northern, central and southern highlands. A fourth, clearly differentiated cluster was also found and included individuals from locations at higher elevations. We suggest that the population structure of the species could be explained by an isolation-by-distance model and can be associated with the geological history of the Andean region. Our results suggest that elevation could also be a key factor in the differentiation of mortiño populations. This study provides an extensive overview of the species across its distribution range in Ecuador, contributing to a better understanding of its conservation status. These results can assist in the development of conservation programs for this valuable biological and cultural resource and for the páramo ecosystem as a whole.

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BOTERO-DELGADILLO, ESTEBAN, CARLOS ANDRÉS PÁEZ, and NICHOLAS BAYLY. "Biogeography and conservation of Andean and Trans-Andean populations of Pyrrhura parakeets in Colombia: Modelling geographic distributions to identify independent conservation units." Bird Conservation International 22, no. 4 (May 18, 2012): 445–61. http://dx.doi.org/10.1017/s0959270912000196.

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SummaryThe criteria and categories of the IUCN red list can be applied to any taxonomic unit, including taxa below species level or non-formally described forms, but this is seldom practiced. Because conservation priorities largely focus on well-established taxa that deserve urgent action, cryptic species may be facing a critical situation. This could be the case for some Andean and trans-Andean populations of Pyrrhura parakeets in Colombia that have restricted and isolated geographic ranges, and whose conservation status has been overlooked because nominal species covering them are considered of “Least Concern”. As part of research into the biogeographic history and biogeographic patterns of the genus Pyrrhura, we used MaxEnt modelling to make a first approach to the geographic distribution and conservation status of these populations, and to determine if they could be considered independent conservation units. As with other members of Pyrrhura, we found that their climatic niche was restricted to humid regions of the Andes and the Andean foothills, resulting in isolated and discontinuous distributions associated with the Tropical humid forest Zonobiome. Comparing our estimates of area of occupancy with the established thresholds for IUCN criterion B2, the four subspecies studied could be considered threatened. The small geographic ranges, apparent vulnerability to forest fragmentation compared with other parrots, and extensive habitat loss experienced by the Andean and trans-Andean subspecies of P. melanura and P. picta allow us to conclude that they are valid conservation units. Although further research on these taxa is necessary, our results imply that they must be included as target populations in local and national policies for management plans and decision making, and urgent actions are needed for the subspecies of P. picta such as P. p. subandina and P. p. caeruleiceps.

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Dias, Vanessa S., Guy J. Hallman, Amanda A. S. Cardoso, Nick V. Hurtado, Camilo Rivera, Florence Maxwell, Carlos E. Cáceres-Barrios, Marc J. B. Vreysen, and Scott W. Myers. "Relative Tolerance of Three Morphotypes of the Anastrepha fraterculus Complex (Diptera: Tephritidae) to Cold Phytosanitary Treatment." Journal of Economic Entomology 113, no. 3 (March 12, 2020): 1176–82. http://dx.doi.org/10.1093/jee/toaa027.

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Abstract The Anastrepha fraterculus (Wiedemann) complex is currently comprised of at least eight morphotypes, including several that are likely to be described as new species. It is critical to evaluate whether the morphotypes differ in tolerance to phytosanitary treatments. Temperatures from 0 to 3°C are used as a phytosanitary treatment for some commodities exported from the region and at risk of infestation by the A. fraterculus complex. Description of A. fraterculus morphotypes as new species could result in the annulation of phytosanitary treatment schedules for the new species. This study compared the relative cold tolerance of five populations from three morphotypes of the A. fraterculus complex: Andean, Peruvian, and Brazilian-1. Both a laboratory and wild strain of the Brazilian-1 morphotype were studied. Differences in mortality of third instars of the five A. fraterculus populations reared on nectarines were observed only with short treatment durations at temperatures ranging from 1.38 ± 0.04°C to 1.51 ± 0.08°C (mean ± SEM). Estimated times to achieve the LT99.99682 (probit 9) showed that Brazilian-1 wild, Brazilian-1 laboratory, and Cusco population were the most cold tolerant, followed by Andean and Peruvian, the least cold tolerant morphotype (i.e., Brazilian-1 wild = Brazilian-1 laboratory = Cusco population > Andean > Peruvian). These findings suggest that the current cold treatment schedules of 15 d at ≤ 1.11°C and 17 d at ≤ 1.67°C can be applied as cold treatments to any potential new species that may arise from the A. fraterculus complex.

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Lindo, John, Randall Haas, Courtney Hofman, Mario Apata, Mauricio Moraga, Ricardo A. Verdugo, James T. Watson, et al. "The genetic prehistory of the Andean highlands 7000 years BP though European contact." Science Advances 4, no. 11 (November 2018): eaau4921. http://dx.doi.org/10.1126/sciadv.aau4921.

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The peopling of the Andean highlands above 2500 m in elevation was a complex process that included cultural, biological, and genetic adaptations. Here, we present a time series of ancient whole genomes from the Andes of Peru, dating back to 7000 calendar years before the present (BP), and compare them to 42 new genome-wide genetic variation datasets from both highland and lowland populations. We infer three significant features: a split between low- and high-elevation populations that occurred between 9200 and 8200 BP; a population collapse after European contact that is significantly more severe in South American lowlanders than in highland populations; and evidence for positive selection at genetic loci related to starch digestion and plausibly pathogen resistance after European contact. We do not find selective sweep signals related to known components of the human hypoxia response, which may suggest more complex modes of genetic adaptation to high altitude.

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Tordable, M. del C., A. J. Andrade, M. E. Doucet, and P. Lax. "Histopathology of Andean Potato (Solanum tuberosum Andigenum group) varieties parasitized by the false root-knot nematode, Nacobbus aberrans." Brazilian Journal of Biology 78, no. 4 (February 1, 2018): 679–85. http://dx.doi.org/10.1590/1519-6984.172401.

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Abstract Landraces of the Solanum tuberosum Andigenum group are abundant and diverse. They are a valuable genetic resource possessing resistance to pests, diseases, and environmental stresses. In the Andean region, populations of the false root-knot nematode Nacobbus aberrans became specialized to infect native potatoes, being one of the major limiting factors affecting this crop. A better understanding of the host plant-parasite interactions is important in order to select tolerant or resistant plants to be included in management programs. Despite the close of association of N. aberrans with potato, and the great diversity of the S. tuberosum Andigenum group, few histopathological studies have been conducted. The aim of this work was to analyze histological alterations induced by different Argentine populations of the nematode in naturally infested roots of four Andean potato varieties (Collareja, Negra Imilla, Ojo de Señorita and Colorada). All the varieties showed hyperplastic tissue in the central zone of galls, where syncytia developed in close association with the nematode female. Syncytia were composed of modified hyperplastic tissue and parenchyma xylem cells. The results showed differences among varieties in their response to nematode populations, with Ojo de Señorita and Negra Imilla being the most susceptible ones. This study is the first describing histopathological alterations induced by N. aberrans in susceptible Andean potato landraces.

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Leonard, W. R., T. L. Leatherman, J. W. Carey, and R. B. Thomas. "Contributions of nutrition versus hypoxia to growth in rural Andean populations." American Journal of Human Biology 2, no. 6 (1990): 613–26. http://dx.doi.org/10.1002/ajhb.1310020605.

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Apata, Mario, Bernado Arriaza, Elena Llop, and Mauricio Moraga. "Human adaptation to arsenic in Andean populations of the Atacama Desert." American Journal of Physical Anthropology 163, no. 1 (February 16, 2017): 192–99. http://dx.doi.org/10.1002/ajpa.23193.

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Castello, Lucía V., Michael H. J. Barfuss, Walter Till, Leonardo Galetto, and Jorge O. Chiapella. "Disentangling theTillandsia capillariscomplex: phylogenetic relationships and taxon boundaries in Andean populations." Botanical Journal of the Linnean Society 181, no. 3 (March 18, 2016): 391–414. http://dx.doi.org/10.1111/boj.12400.

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Frisancho, A. R. "Origins of differences in hemoglobin concentration between Himalayan and Andean populations." Respiration Physiology 72, no. 1 (April 1988): 13–18. http://dx.doi.org/10.1016/0034-5687(88)90075-8.

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Arriaza, Bernardo, Vivien Standen, Karl Reinhard, Adauto Araújo, Jörg Heukelbach, and Katharina Dittmar. "On head lice and social interaction in archaic Andean coastal populations." International Journal of Paleopathology 3, no. 4 (December 2013): 257–68. http://dx.doi.org/10.1016/j.ijpp.2013.10.001.

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López Steinmetz, Lorena Cecilia, Romina Lucrecia López Steinmetz, and Juan Carlos Godoy. "Is unemployment less important than expected for suicide attempted in developing regions? Occupational profile of suicide attempts in Jujuy, north westernmost Argentina." International Journal of Social Psychiatry 66, no. 1 (October 17, 2019): 67–75. http://dx.doi.org/10.1177/0020764019882728.

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Background: Mental health practices consider unemployment as a suicide main risk factor, based on models built for populations of developed countries. Aim: This study assesses the association between the occupational risk factor and suicidal behaviors, by considering sex, age and temporal distribution, in a Latin American Andean population from north westernmost Argentina. Methods: Data include 481 suicide attempt cases assisted by emergency service psychologists at a head hospital in the Jujuy Province, northern Argentina, during two biennials. General categories and specific types of occupational situation, sex, age and temporal distribution were analyzed. Results: 83.58% of cases corresponded to the with occupation category, but without occupation characterized male cases ( p-value = .01). The type no referred occupation (19.15%) mainly contributed to this association ( p-value = .02). Unemployed only represented 1.6%. These features revealed independent from the biennial period of assistance ( p-value = .96 (general), p-value = .86 (specific)). Associations by age ranges did not seem to be specific of suicidal attempts. Conclusion: The present contribution provides an occupational characterization of suicide attempts in an Andean population from north westernmost Argentina. Unemployment is not associated with suicidal behavior in this population, suggesting that dissimilar patterns underlie suicidal behavior of populations from developed and developing regions.

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Fuentes, Segundo, Adrian J. Gibbs, Mohammad Hajizadeh, Ana Perez, Ian P. Adams, Cesar E. Fribourg, Jan Kreuze, Adrian Fox, Neil Boonham, and Roger A. C. Jones. "The Phylogeography of Potato Virus X Shows the Fingerprints of Its Human Vector." Viruses 13, no. 4 (April 9, 2021): 644. http://dx.doi.org/10.3390/v13040644.

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Potato virus X (PVX) occurs worldwide and causes an important potato disease. Complete PVX genomes were obtained from 326 new isolates from Peru, which is within the potato crop′s main domestication center, 10 from historical PVX isolates from the Andes (Bolivia, Peru) or Europe (UK), and three from Africa (Burundi). Concatenated open reading frames (ORFs) from these genomes plus 49 published genomic sequences were analyzed. Only 18 of them were recombinants, 17 of them Peruvian. A phylogeny of the non-recombinant sequences found two major (I, II) and five minor (I-1, I-2, II-1, II-2, II-3) phylogroups, which included 12 statistically supported clusters. Analysis of 488 coat protein (CP) gene sequences, including 128 published previously, gave a completely congruent phylogeny. Among the minor phylogroups, I-2 and II-3 only contained Andean isolates, I-1 and II-2 were of both Andean and other isolates, but all of the three II-1 isolates were European. I-1, I-2, II-1 and II-2 all contained biologically typed isolates. Population genetic and dating analyses indicated that PVX emerged after potato’s domestication 9000 years ago and was transported to Europe after the 15th century. Major clusters A–D probably resulted from expansions that occurred soon after the potato late-blight pandemic of the mid-19th century. Genetic comparisons of the PVX populations of different Peruvian Departments found similarities between those linked by local transport of seed potato tubers for summer rain-watered highland crops, and those linked to winter-irrigated crops in nearby coastal Departments. Comparisons also showed that, although the Andean PVX population was diverse and evolving neutrally, its spread to Europe and then elsewhere involved population expansion. PVX forms a basal Potexvirus genus lineage but its immediate progenitor is unknown. Establishing whether PVX′s entirely Andean phylogroups I-2 and II-3 and its Andean recombinants threaten potato production elsewhere requires future biological studies.

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Arteaga, Sugenith, Lourdes Yabor, José Torres, Eva Solbes, Enrique Muñoz, María José Díez, Oscar Vicente, and Monica Boscaiu. "Morphological and Agronomic Characterization of Spanish Landraces of Phaseolus vulgaris L." Agriculture 9, no. 7 (July 9, 2019): 149. http://dx.doi.org/10.3390/agriculture9070149.

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Beans (Phaseolus vulgaris L.) originated on the American continent, specifically in the Mesoamerican zone, and their domestication took place independently in the Mesoamerican area and the Andean zone, giving rise to two well-differentiated genetic pools. It was also noted that the Andean wild populations originated from only a few thousand individuals from the Mesoamerican wild populations, which produced a great bottleneck in the formation of the Andean population. During centuries of cultivation in the Iberian Peninsula after its introduction in the 16th century, beans adapted to new environments, evolving numerous local landraces. Twenty-four local landraces of P. vulgaris from Spain were analyzed in the greenhouse during two consecutive seasons. From each genotype, five plants were grown and characterized for 17 quantitative and 15 qualitative traits using the International Board for Plant Genetic Resources (IBPGR) descriptors. Data were analyzed statistically by analysis of variance (ANOVA), principal component analysis (PCA), and cluster analysis. The results obtained indicate a high variability for most traits, especially those related to the yield and its components. The PCA and cluster analysis separated the landraces according to the color of the seed, the yield, and the pod and seed traits related to yield. Numerous traits exhibited interactions between the genotype and the environment. Most accessions reached higher yields in spring, in which solar radiation favors photosynthesis and, consequently, photoassimilation. The different response to the changing environment of the set of accessions studied in the present work is of great interest, and it can be exploited in breeding cultivars adapted to a broader range of environmental conditions.

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Alvarez-Flores, Ricardo, Thierry Winkel, David Degueldre, Carmen Del Castillo, and Richard Joffre. "Plant growth dynamics and root morphology of little-known species of Chenopodium from contrasted Andean habitats." Botany 92, no. 2 (February 2014): 101–8. http://dx.doi.org/10.1139/cjb-2013-0224.

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Plant morphology determines the access to soil resources, a feature crucial for early growth in annual species. Plant growth and root traits in little-known species of Andean chenopods were compared with the hypothesis that plants from low-resource habitats show traits that enhance resource capture. Three cultivated Chenopodium populations (two populations of the tetraploid Chenopodium quinoa Willd., one population of the diploid Chenopodium pallidicaule Aellen) and one population of their wild tetraploid relative Chenopodium hircinum Schrad. were grown in pots under nonlimiting conditions over nine weeks of early vegetative growth. All populations followed the same sequence of biomass allocation and showed similar maximal values of shoot and root relative growth rates (RGR). Population differences in plant biomass, net assimilation rate, total root length, and specific root length were associated with seed mass ranking and species ploidy level. Chenopodium quinoa produced less branched stems and maintained high root RGR for a longer time than the other two species, and the C. quinoa population from low-resource habitat showed a faster main root growth. These results show that C. pallidicaule developed a plant growth syndrome adapted to cold, high-altitude habitats, while C. quinoa from low-resource habitats showed an improved capacity to explore soil at depth in early growth stages.

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Espinosa, Mara I., Nicolas Gouin, Francisco A. Squeo, David López, and Angéline Bertin. "Landscape connectivity among remnant populations of guanaco (Lama guanicoe Müller, 1776) in an arid region of Chile impacted by global change." PeerJ 6 (March 2, 2018): e4429. http://dx.doi.org/10.7717/peerj.4429.

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Connectivity between populations plays a key role in the long-term persistence of species in fragmented habitats. This is of particular concern for biodiversity preservation in drylands, since water limited landscapes are typically characterized by little suitable habitat cover, high habitat fragmentation, harsh matrices, and are being rapidly degraded at a global scale. In this study, we modelled landscape connectivity between 11 guanaco Lama guanicoe populations in Chile’s arid Norte Chico, a region that supports the last remnant coastal populations of this emblematic herbivore indigenous to South America. We produced a habitat suitability model to derive a regional surface resistance map, and used circuit theory to map functional connectivity, investigate the relative isolation between populations, and identify those that contribute most to the patch connectivity network. Predicted suitable habitat for L. guanicoe represented about 25% of the study region (i.e., 29,173 km2) and was heterogeneously distributed along a continuous stretch along the Andes, and discontinuous patches along the coast. As a result, we found that high connectivity current flows in the mid and high Andes formed a wide, continuous connectivity corridor, enabling connectivity between all high Andean populations. Coastal populations, in contrast, were more isolated. These groups demonstrate no inter-population connectivity between themselves, only with higher altitude populations, and for two of them, animal movement was linked to the effectiveness of wildlife crossings along the Pan-American highway. Our results indicate that functional connectivity is an issue of concern for L. guanicoe in Chile’s Norte Chico, implying that future conservation and management plans should emphasize strategies aimed at conserving functional connectivity between coastal and Andean populations, as well as the protection of habitat patches likely to act as stepping stones within the connectivity network.

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Ruiz-García, Manuel, Jessica Yanina Arias Vásquez, Héctor Restrepo, Carlos Herney Cáceres-Martínez, and Joseph Mark Shostell. "The genetic structure of the spectacled bear (Tremarctos ornatus; Ursidae, Carnivora) in Colombia by means of mitochondrial and microsatellite markers." Journal of Mammalogy 101, no. 4 (August 25, 2020): 1072–90. http://dx.doi.org/10.1093/jmammal/gyaa082.

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Abstract The spectacled bear (Ursidae: Tremarctos ornatus) is an emblematic umbrella species and one of the top carnivores in the Andean mountains. It is also listed as vulnerable by IUCN and as endangered by CITES. We analyzed the genetic structure of this species in nine geographical regions representing the three Andean Cordilleras in Colombia. We sequenced six mitochondrial genes in 115 spectacled bears; a subset of these specimens (n = 61) were genotyped at seven nuclear microsatellites. We addressed three objectives: 1) determine the genetic diversity and historical demographic changes of the spectacled bear in Colombia; 2) determine phylogeographic patterns of genetic divergence among spectacled bear populations in Colombia; and 3) estimate the levels of gene flow among different regions of Colombia. Our analyses show evidence of high mitochondrial genetic diversity in spectacled bears, both in Colombia as well as in each of the nine regions, most particularly Norte de Santander, Nariño, and Antioquia-Córdoba. In addition, we detected population expansion in Colombia that occurred around 24,000 years ago, followed by a population decrease during the last 7,000 years, and a sudden expansion in the last 300 years. Phylogenetic analyses showed few well-supported clades, with some haplotypes detected in all the departments and Colombian Andean Cordilleras, and other haplotypes restricted to certain geographical areas (Antioquia, Norte de Santander, Cundinamarca, and Nariño). We detected significant genetic heterogeneity among some departments and among the three Colombian Andean Cordilleras for both mitochondrial and nuclear genes. Nevertheless, the moderate levels of gene flow estimated from FST statistics suggest that geographical barriers have not been definitive obstacles to the dispersion of the spectacled bear throughout Colombia. Despite these gene flow estimates, significant spatial autocorrelation was detected for spectacled bear in Colombia, where two kinds of spatial patterns were discovered: genetic patches of 144 km of diameter, and isolation by distance among bears separated from 578 to 800 km. The two most northern spectacled bear populations of Colombia (Norte de Santander and Antioquia) also were the two most differentiated. Their distinctiveness may qualify them as distinct Management Units (MUs) in the context of conservation policies for the spectacled bear in Colombia.

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Tabbabi, Ahmed, Shinya Watanabe, Daiki Mizushima, Abraham G. Caceres, Eduardo A. Gomez, Daisuke S. Yamamoto, Longzhu Cui, Yoshihisa Hashiguchi, and Hirotomo Kato. "Comparative Analysis of Bacterial Communities in Lutzomyia ayacuchensis Populations with Different Vector Competence to Leishmania Parasites in Ecuador and Peru." Microorganisms 9, no. 1 (December 29, 2020): 68. http://dx.doi.org/10.3390/microorganisms9010068.

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Differences in the gut microbial content of Lutzomyia (Lu.) ayacuchensis, a primary vector of Andean-type cutaneous leishmaniasis in Ecuador and Peru, may influence the susceptibility of these sand flies to infection by Leishmania. As a first step toward addressing this hypothesis, a comparative analysis of bacterial and fungal compositions from Lu. ayacuchensis populations with differential susceptibilities to Leishmania was performed. Bacterial 16S rRNA gene amplification and Illumina MiSeq sequencing approaches were used to characterize the bacterial composition in wild-caught populations from the Andean areas of Ecuador and southern Peru at which the sand fly species transmit Leishmania (Leishmania) mexicana and Leishmania (Viannia) peruviana, respectively, and a population from the northern Peruvian Andes at which the transmission of Leishmania by Lu. ayacuchensis has not been reported. In the present study, 59 genera were identified, 21 of which were widely identified and comprised more than 95% of all bacteria. Of the 21 dominant bacterial genera identified in the sand flies collected, 10 genera had never been detected in field sand flies. The Ecuador and southern Peru populations each comprised individuals of particular genera, while overlap was clearly observed between microbes isolated from different sites, such as the number of soil organisms. Similarly, Corynebacterium and Micrococcus were slightly more dominant bacterial genera in the southern Peru population, while Ochrobactrum was the most frequently isolated from other populations. On the other hand, fungi were only found in the southern Peru population and dominated by the Papiliotrema genus. These results suggest that variation in the insect gut microbiota may be elucidated by the ecological diversity of sand flies in Peru and Ecuador, which may influence susceptibility to Leishmania infection. The present study provides key insights for understanding the role of the microbiota during the course of L. (L.) mexicana and L. (V.) peruviana infections in this important vector.

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Raker, Celeste M., and David M. Spooner. "Chilean Tetraploid Cultivated Potato, Solanum tuberosum , is Distinct from the Andean Populations." Crop Science 42, no. 5 (September 2002): 1451–58. http://dx.doi.org/10.2135/cropsci2002.1451.

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Barrett, Spencer C. H., and Mary T. K. Arroyo. "Variation in floral morph ratios in tristylous Oxalis squamata (Oxalidaceae): an Andean alpine endemic." Botany 90, no. 11 (November 2012): 1180–85. http://dx.doi.org/10.1139/b2012-075.

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Negative frequency-dependent selection resulting from disassortative mating should result in equal morph ratios in tristylous populations at equilibrium. However, surveys of morph-frequency variation in tristylous species commonly report deviations from equality. Here, we report variation in morph ratios in Oxalis squamata Zucc., an endemic of the Andean region of Chile and Argentina. Absence of clonal propagation in this species allows unambiguous estimates of the morph ratio of genets. We sampled floral morph ratios in 20 populations occurring in Central Chile and investigated the relation between morph evenness in populations and their size. All populations of O. squamata were tristylous but with significant heterogeneity among populations in morph ratios. Although small populations exhibited a greater variance in morph evenness, biased ratios were also evident in several large populations. We found no evidence of morph loss or a consistent bias in morph frequencies as reported in some tristylous species. Biased morph frequencies in large populations probably arise from episodic sexual recruitment following disturbance and a slow approach to equilibrium.

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SOLERVICENS, JAIME A. "Cladistic analysis of the species of Calendyma Lacordaire (1857) and Epiclines Chevrolat (1838) (Coleoptera: Cleridae: Clerinae)." Zootaxa 1497, no. 1 (June 4, 2007): 57–68. http://dx.doi.org/10.11646/zootaxa.1497.1.6.

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This work presents a cladistic analysis of the species of the genera Calendyma Lacordaire (1857) and Epiclines Chevrolat (1838), and briefly considers the genus Eleale Newman (1840). Three species of the genus Neogyponyx Schenkling (1906) are considered as the outgroup for the phylogenetic analysis. The three genera studied share several characteristics that establish their monophyly. It is postulated that these three genera originated from the austral parts of Gondwana, and that flower feeding was a strong adaptive force in their evolution. It is further postulated that the genera Calendyma and Epiclines differentiated populations to the east and west side of the Andean cordillera, during the Andean uplift, and that their western populations may have evolved from ancestors inhabiting shrubby marginal habitats of southern Chilean temperate forests, then spread to lower latitudes. Vicariant events seem to have differentiated Chilean species of Calendyma and Epiclines around 31º South latitude.

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Lim, Marisa C. W., Ke Bi, Christopher C. Witt, Catherine H. Graham, and Liliana M. Dávalos. "Pervasive Genomic Signatures of Local Adaptation to Altitude Across Highland Specialist Andean Hummingbird Populations." Journal of Heredity 112, no. 3 (February 25, 2021): 229–40. http://dx.doi.org/10.1093/jhered/esab008.

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Abstract Populations along steep environmental gradients are subject to differentiating selection that can result in local adaptation, despite countervailing gene flow, and genetic drift. In montane systems, where species are often restricted to narrow ranges of elevation, it is unclear whether the selection is strong enough to influence functional differentiation of subpopulations differing by a few hundred meters in elevation. We used targeted capture of 12 501 exons from across the genome, including 271 genes previously implicated in altitude adaptation, to test for adaptation to local elevations for 2 highland hummingbird species, Coeligena violifer (n = 62) and Colibri coruscans (n = 101). For each species, we described population genetic structure across the complex geography of the Peruvian Andes and, while accounting for this structure, we tested whether elevational allele frequency clines in single nucleotide polymorphisms (SNPs) showed evidence for local adaptation to elevation. Although the 2 species exhibited contrasting population genetic structures, we found signatures of clinal genetic variation with shifts in elevation in both. The genes with SNP-elevation associations included candidate genes previously discovered for high-elevation adaptation as well as others not previously identified, with cellular functions related to hypoxia response, energy metabolism, and immune function, among others. Despite the homogenizing effects of gene flow and genetic drift, natural selection on parts of the genome evidently optimizes elevation-specific cellular function even within elevation range-restricted montane populations. Consequently, our results suggest local adaptation occurring in narrow elevation bands in tropical mountains, such as the Andes, may effectively make them “taller” biogeographic barriers.

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Guevara, Evelyn K., Jukka U. Palo, Sanni Översti, Jonathan L. King, Maria Seidel, Monika Stoljarova, Frank R. Wendt, et al. "Genetic assessment reveals no population substructure and divergent regional and sex-specific histories in the Chachapoyas from northeast Peru." PLOS ONE 15, no. 12 (December 31, 2020): e0244497. http://dx.doi.org/10.1371/journal.pone.0244497.

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Many native populations in South America have been severely impacted by two relatively recent historical events, the Inca and the Spanish conquest. However decisive these disruptive events may have been, the populations and their gene pools have been shaped markedly also by the history prior to the conquests. This study focuses mainly on the Chachapoya peoples that inhabit the montane forests on the eastern slopes of the northern Peruvian Andes, but also includes three distinct neighboring populations (the Jívaro, the Huancas and the Cajamarca). By assessing mitochondrial, Y-chromosomal and autosomal diversity in the region, we explore questions that have emerged from archaeological and historical studies of the regional culture (s). These studies have shown, among others, that Chachapoyas was a crossroads for Coast-Andes-Amazon interactions since very early times. In this study, we examine the following questions: 1) was there pre-Hispanic genetic population substructure in the Chachapoyas sample? 2) did the Spanish conquest cause a more severe population decline on Chachapoyan males than on females? 3) can we detect different patterns of European gene flow in the Chachapoyas region? and, 4) did the demographic history in the Chachapoyas resemble the one from the Andean area? Despite cultural differences within the Chachapoyas region as shown by archaeological and ethnohistorical research, genetic markers show no significant evidence for past or current population substructure, although an Amazonian gene flow dynamic in the northern part of this territory is suggested. The data also indicates a bottleneck c. 25 generations ago that was more severe among males than females, as well as divergent population histories for populations in the Andean and Amazonian regions. In line with previous studies, we observe high genetic diversity in the Chachapoyas, despite the documented dramatic population declines. The diverse topography and great biodiversity of the northeastern Peruvian montane forests are potential contributing agents in shaping and maintaining the high genetic diversity in the Chachapoyas region.

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Aguirre-Acosta, Natalia, and Jorge Eduardo Botero-Echeverri. "Estructura poblacional y distribución espacial del roble negro (Colombobalanus excelsa, Fagaceae), especie endémica, en fragmentos de bosque andino colombiano." Revista de Biología Tropical 66, no. 2 (May 24, 2018): 486. http://dx.doi.org/10.15517/rbt.v66i2.33376.

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Population structure and spatial distribution of black oak (Colombobalanus excelsa, Fagaceae), endemic species, in Colombian Andean forest fragments. The Colombian Andean forests are recognized for its great biodiversity and endemism; however, they have undergone a severe process of fragmentation due to anthropic factors. As a result, many vulnerable species have been especially affected. That is the case of the black oak (Colombobalanus excelsa (Lozano, Hern. Cam., & Henao) Nixon & Crepet), an endemic and poorly studied species of the Colombian Andes, which has a distribution restricted to only four areas in the country, one of which is the Southeastern Huila region. To examine black oak populations in Serranía Peñas Blancas (Huila), in 2006 we studied the age structure and spatial distribution in plots of 50 x 20 m (1.6 ha) in forest fragments, in southern distribution. In total, 1 228 black oak species were registered among saplings, juvenile and adults, and they have distribution patterns Gamma and Weibull. These results confirm that the majority of the individuals are in the first diametric class. Also, these populations show an added distribution pattern due to the wood extraction process. These results indicate that black oak populations are in a recovery phase after forceful anthropic intervention. Knowing the current status of black oak forests can contribute to the design of effective conservation plans of this species in Colombia. Rev. Biol. Trop. 66(2): 486-494. Epub 2018 June 01.

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Aguilar, Juan M. "Geographic distribution analysis of the genus Xenodacnis (Birds: Thraupidae) using ecological niche modeling." Revista Peruana de Biología 26, no. 3 (September 29, 2019): 317–24. http://dx.doi.org/10.15381/rpb.v26i3.16775.

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Xenodacnis is a monotypic thraupid genus restricted to the tropical high Andes of Peru and Ecuador. Its only species, X. parina has a large discontinuous distribution from central Ecuador to southern Peru. To date, three subspecies are recognized, all separated by geographical barriers that clouded promote allopatric events. The taxonomic affinities of the Ecuadorian population have not been assessed since its discovery in the 1970s at the Cajas National Park in Azuay province. I studied the environmental affinities between the distribution of the described subspecies and the Ecuadorian population bias ecological niche modeling. I found a distinctive ecological niche in the distribution of each of the analyzed populations and also for the southern Arequipa population. These different environmental niche conditions come apart by deep Andean valleys playing a role as geographical barriers for the isolation of these populations that need further taxonomic analysis.

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Apata, Mario, and Susanne P. Pfeifer. "Recent population genomic insights into the genetic basis of arsenic tolerance in humans: the difficulties of identifying positively selected loci in strongly bottlenecked populations." Heredity 124, no. 2 (November 27, 2019): 253–62. http://dx.doi.org/10.1038/s41437-019-0285-0.

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AbstractRecent advances in genomics have enabled researchers to shed light on the evolutionary processes driving human adaptation, by revealing the genetic architectures underlying traits ranging from lactase persistence, to skin pigmentation, to hypoxic response, to arsenic tolerance. Complicating the identification of targets of positive selection in modern human populations is their complex demographic history, characterized by population bottlenecks and expansions, population structure, migration, and admixture. In particular, founder effects and recent strong population size reductions, such as those experienced by the indigenous peoples of the Americas, have severe impacts on genetic variation that can lead to the accumulation of large allele frequency differences between populations due to genetic drift rather than natural selection. While distinguishing the effects of demographic history from selection remains challenging, neglecting neutral processes can lead to the incorrect identification of candidate loci. We here review the recent population genomic insights into the genetic basis of arsenic tolerance in Andean populations, and utilize this example to highlight both the difficulties pertaining to the identification of local adaptations in strongly bottlenecked populations, as well as the importance of controlling for demographic history in selection scans.

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Valverde, Guido, Hang Zhou, Sebastian Lippold, Cesare de Filippo, Kun Tang, David López Herráez, Jing Li, and Mark Stoneking. "A Novel Candidate Region for Genetic Adaptation to High Altitude in Andean Populations." PLOS ONE 10, no. 5 (May 11, 2015): e0125444. http://dx.doi.org/10.1371/journal.pone.0125444.

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Baca, Mateusz, Martyna Molak, Maciej Sobczyk, Piotr Węgleński, and Anna Stankovic. "Locals, resettlers, and pilgrims: A genetic portrait of three pre-Columbian Andean populations." American Journal of Physical Anthropology 154, no. 3 (May 6, 2014): 402–12. http://dx.doi.org/10.1002/ajpa.22524.

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Zattara, Eduardo E., and Andrea C. Premoli. "Genetic structuring in Andean landlocked populations of Galaxias maculatus: effects of biogeographic history." Journal of Biogeography 32, no. 1 (December 23, 2004): 5–14. http://dx.doi.org/10.1111/j.1365-2699.2004.01164.x.

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Brutsaert, Tom D. "Limits on Inferring Genetic Adaptation to High Altitude in Himalayan and Andean Populations." High Altitude Medicine & Biology 2, no. 2 (June 2001): 211–25. http://dx.doi.org/10.1089/152702901750265314.

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Cattan-Toupance, I., Y. Michalakis, and C. Neema. "Genetic structure of wild bean populations in their South-Andean centre of origin." Theoretical and Applied Genetics 96, no. 6-7 (May 1998): 844–51. http://dx.doi.org/10.1007/s001220050811.

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Rhode, Matthew P., and Bernardo T. Arriaza. "Influence of cranial deformation on facial morphology among prehistoric South Central Andean populations." American Journal of Physical Anthropology 130, no. 4 (2006): 462–70. http://dx.doi.org/10.1002/ajpa.20333.

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Sutter, Richard C. "Prehistoric Genetic and Culture Change: A Bioarchaeological Search for Pre-Inka Altiplano Colonies in the Coastal Valleys of Moquegua, Peru, and Azapa, Chile." Latin American Antiquity 11, no. 1 (March 2000): 43–70. http://dx.doi.org/10.2307/1571670.

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This investigation uses a bioarchaeological approach to test the existence of pre-Inka colonists within the Andean coastal valleys of Moquegua, Peru, and Azapa, Chile, as predicted by Murra's (1972) classic model of verticality. The archaeological evidence and biodistance results obtained using genetically controlled dental traits from 859 skeletal and mummified remains indicate that the Late Intermediate period (A.D. 1100-1476) coastal Chiribaya people of the Moquegua Valley, Peru, likely represent descendants of altiplano populations that migrated to the coastal region following the disintegration of the Middle Horizon (A.D. 750-1100) Tiwanaku colony located in the middle Moquegua Valley. In the neighboring Azapa Valley, Chile, genetic change among prehistoric populations was due to gradual in situ microevolution of local populations rather than colonization by altiplano people. Coastal populations of the Azapa Valley maintained biocultural continuity with the Archaic period Chinchorro coastal population. It is concluded that Murra's model of direct verticality should be evaluated using both biological and archaeological data on a case-by-case basis.

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Rupert, J. L., and P. W. Hochachka. "Genetic approaches to understanding human adaptation to altitude in the Andes." Journal of Experimental Biology 204, no. 18 (September 15, 2001): 3151–60. http://dx.doi.org/10.1242/jeb.204.18.3151.

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SUMMARYDespite the initial discomfort often experienced by visitors to high altitude, humans have occupied the Andean altiplano for more than 10000 years, and millions of people, indigenous and otherwise, currently live on these plains, high in the mountains of South America, at altitudes exceeding 3000m. While, to some extent, acclimatisation can accommodate the one-third decrease in oxygen availability, having been born and raised at altitude appears to confer a substantial advantage in high-altitude performance compared with having been born and raised at sea level. A number of characteristics have been postulated to contribute to a high-altitude Andean phenotype; however, the relative contributions of developmental adaptation (within the individual) and genetic adaptation (within the population of which the individual is part) to the acquisition of this phenotype have yet to be resolved.A complex trait is influenced by multiple genetic and environmental factors and, in humans, it is inherently very difficult to determine what proportion of the trait is dictated by an individual’s genetic heritage and what proportion develops in response to the environment in which the person is born and raised. Looking for changes in putative adaptations in vertically migrant populations, determining the heritability of putative adaptive traits and genetic association analyses have all been used to evaluate the relative contributions of nurture and nature to the Andean phenotype. As the evidence for a genetic contribution to high-altitude adaptation in humans has been the subject of several recent reviews, this article instead focuses on the methodology that has been employed to isolate the effects of ‘nature’ from those of ‘nurture’ on the acquisition of the high-altitude phenotype in Andean natives (Quechua and Aymara). The principles and assumptions underlying the various approaches, as well as some of the inherent strengths and weaknesses of each, are briefly discussed.

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Urrunaga-Pastor, Diego, Fernando M. Runzer-Colmenares, Tania M. Arones, Rosario Meza-Cordero, Silvana Taipe-Guizado, Jack M. Guralnik, and Jose F. Parodi. "Factors associated with poor physical performance in older adults of 11 Peruvian high Andean communities." F1000Research 8 (January 15, 2019): 59. http://dx.doi.org/10.12688/f1000research.17513.1.

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Background: Physical performance in the older adult has been extensively studied. However, only a few studies have evaluated physical performance among older adults of high Andean populations and none have studied the factors associated with it. The objective of this study was to evaluate factors associated with poor physical performance by using the Short Physical Performance Battery (SPPB) in older adults living in 11 Peruvian high Andean communities. Methods: An analytical cross-sectional study was carried out in inhabitants aged 60 or over from 11 high-altitude Andean communities of Peru during 2013-2017. Participants were categorized in two groups according to their SPPB score: poor physical performance (0-6 points) and medium/good physical performance (7-12 points). Additionally, we collected socio-demographic, medical, functional and cognitive assessment information. Poisson regression models were constructed to identify factors associated with poor physical performance. Prevalence ratio (PR) with 95% confidence intervals (95 CI%) are presented. Results: A total of 407 older adults were studied. The average age was 73.0 ± 6.9 years (range: 60-94 years) and 181 (44.5%) participants had poor physical performance (0-6 points). In the adjusted Poisson regression analysis, the factors associated with poor physical performance were: female gender (PR=1.29; 95%CI: 1.03-1.61), lack of social support (PR=2.10; 95%CI: 1.17-3.76), number of drugs used (PR=1.09; 95%CI: 1.01-1.17), urinary incontinence (PR=1.45; 95%CI: 1.16-1.82), exhaustion (PR=1.35; 95%CI: 1.03-1.75) and cognitive impairment (PR=1.89; 95%CI: 1.40-2.55). Conclusions: Almost half of the population evaluated had poor physical performance based on the SPPB. Factors that would increase the possibility of suffering from poor physical performance were: female gender, lack of social support, number of drugs used, urinary incontinence, exhaustion and cognitive impairment. Future studies with a larger sample and longitudinal follow-up are needed to design beneficial interventions for the high Andean population.

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Journal articles on the topic 'Andean populations'

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