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Facial asymmetries are usually measured and interpreted as proxies to developmental noise. However, analyses focused on its developmental and genetic architecture are scarce. To advance on this topic, studies based on a comprehensive and simultaneous analysis of modularity, morphological integration and facial asymmetries including both phenotypic and genomic information are needed. Here we explore several modularity hypotheses on a sample of Latin American mestizos, in order to test if modularity and integration patterns differ across several genomic ancestry backgrounds. To do so, 4104 individuals were analyzed using 3D photogrammetry reconstructions and a set of 34 facial landmarks placed on each individual. We found a pattern of modularity and integration that is conserved across sub-samples differing in their genomic ancestry background. Specifically, a signal of modularity based on functional demands and organization of the face is regularly observed across the whole sample. Our results shed more light on previous evidence obtained from Genome Wide Association Studies performed on the same samples, indicating the action of different genomic regions contributing to the expression of the nose and mouth facial phenotypes. Our results also indicate that large samples including phenotypic and genomic metadata enable a better understanding of the developmental and genetic architecture of craniofacial phenotypes. Fil: Quinto Sanchez, Mirsha Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Muñoz-Muñoz, Francesc. Universidad Nacional Autónoma de México; México Fil: Gomez-Valdes, Jorge. Universitat Autònoma de Barcelona; España Fil: Cintas, Celia. Instituto Nacional de Antropologia E Historia, Mexico; México Fil: Navarro, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; Argentina Fil: Cerqueira, Caio Cesar Silva De. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Paschetta, Carolina Andrea. Equipe de Perícias Criminalísticas de Ourinhos; Fil: de Azevedo, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; Argentina Fil: Ramallo, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; Argentina Fil: Acuña-Alonzo, Victor. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Adhikari, Kaustubh. Colegio Universitario de Londres; Reino Unido Fil: Fuentes-Guajardo, MacArena. Instituto Nacional de Antropologia E Historia, Mexico; México Fil: Hünemeier, Tábita. Colegio Universitario de Londres; Reino Unido Fil: Everardo, Paola. Universidad de Tarapaca de Arica; Chile Fil: De Avila, Francisco. Colegio Universitario de Londres; Reino Unido Fil: Jaramillo, Claudia. Universidade de Sao Paulo; Brasil Fil: Arias, Williams. Instituto Nacional de Antropologia E Historia, Mexico; México Fil: Gallo, Carla. Universidad Nacional Autónoma de México; México Fil: Poletti, Giovani. Instituto Nacional de Antropologia E Historia, Mexico; México Fil: Bedoya Berrío, Gabriel. Universidad de Antioquia; Colombia Fil: Bortolini, Maria Catira. Universidad de Antioquia; Colombia Fil: Canizales-Quinteros, Samuel. Universidad Peruana Cayetano Heredia; Perú Fil: Rothhammer, Francisco. Universidad Peruana Cayetano Heredia; Perú Fil: Rosique, Javier. Universidad de Antioquia; Colombia Fil: Ruiz-Linares, Andres. Universidade Federal do Rio Grande do Sul; Brasil Fil: González José, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; Argentina

Fluctuating and directional asymmetry are aspects of morphological variation widely used to infer environmental and genetic factors affecting facial phenotypes. However, the genetic basis and environmental determinants of both asymmetry types is far from being completely known. The analysis of facial asymmetries in admixed individuals can be of help to characterize the impact of a genome's heterozygosity on the developmental basis of both fluctuating and directional asymmetries. Here we characterize the association between genetic ancestry and individual asymmetry on a sample of Latin-American admixed populations. To do so, three-dimensional (3D) facial shape attributes were explored on a sample of 4,104 volunteers aged between 18 and 85 years. Individual ancestry and heterozygosity was estimated using more than 730,000 genome-wide markers. Multivariate techniques applied to geometric morphometric data were used to evaluate the magnitude and significance of directional and fluctuating asymmetry (FA), as well as correlations and multiple regressions aimed to estimate the relationship between facial FA scores and heterozygosity and a set of covariates. Results indicate that directional and FA are both significant, the former being the strongest expression of asymmetry in this sample. In addition, our analyses suggest that there are some specific patterns of facial asymmetries characterizing the different ancestry groups. Finally, we find that more heterozygous individuals exhibit lower levels of asymmetry. Our results highlight the importance of including ancestry-admixture estimators, especially when the analyses are aimed to compare levels of asymmetries on groups differing on socioeconomic levels, as a proxy to estimate developmental noise.

The expression of facial asymmetries has been recurrently related with poverty and/or disadvantaged socioeconomic status. Departing from the developmental instability theory, previous approaches attempted to test the statistical relationship between the stress experienced by individuals grown in poor conditions and an increase in facial and corporal asymmetry. Here we aim to further evaluate such hypothesis on a large sample of admixed Latin Americans individuals by exploring if low socioeconomic status individuals tend to exhibit greater facial fluctuating asymmetry values. To do so, we implement Procrustes analysis of variance and Hierarchical Linear Modelling (HLM) to estimate potential associations between facial fluctuating asymmetry values and socioeconomic status. We report significant relationships between facial fluctuating asymmetry values and age, sex, and genetic ancestry, while socioeconomic status failed to exhibit any strong statistical relationship with facial asymmetry. These results are persistent after the effect of heterozygosity (a proxy for genetic ancestry) is controlled in the model. Our results indicate that, at least on the studied sample, there is no relationship between socioeconomic stress (as intended as low socioeconomic status) and facial asymmetries.

Transient natural convection in an open cavity with one inclined wall is analyzed both numerically and experimentally. The fluid and the cavity are in thermal equilibrium at the onset of the experiment. The inclined wall is heated in such a way that the wall temperature increases uniformly according to an hyperbolic tangent function. The transport equations are solved using a 2-D transient model with a non-orthogonal body fitted coordinate system and an exponential grid distribution for better spatial resolution near the inclined wall. Measurements of velocity and temperature are performed at some key points of the boundary layer and intrusion layer. The fluid motion and heat transfer are analyzed from the time at which heat is applied through the inclined wall to the time at which its effect is detected at the opposite sidewall. The main patterns of the fluid flow and heat transfer are well predicted as comparisons against experimental results indicate.