Covariation between the shape and mineralized tissues of the rib cross section in Homo sapiens, Pan troglodytes and Sts 14.

OBJECTIVES: Studying rib torsion is crucial for understanding the evolution of the hominid ribcage. Interestingly, there are variables of the rib cross section that could be associated with rib torsion and, consequently, with the morphology of the thorax. The aim of this research is to conduct a comparative study of the shape and mineralized tissues of the rib cross section in different hominids to test for significant differences and, if possible, associate them to different thoracic morphotypes. MATERIALS AND METHODS: The sample consists of the rib cross sections at the midshaft taken from 10 Homo sapiens and 10 Pan troglodytes adult individuals, as well as from A. africanus Sts 14. The shape of these rib cross sections was quantified using geometric morphometrics, while the mineralized tissues were evaluated using the compartmentalization index. Subsequently, covariation between both parameters was tested by a Spearman's ρ test, a permutation test and a linear regression. RESULTS: Generally, P. troglodytes individuals exhibit rib cross sections that are rounder and more mineralized compared to those of H. sapiens. However, the covariation between both parameters was only observed in typical ribs (levels 3-10). Although covariation was not found in the rib cross sections of Sts 14, their parameters are closer to P. troglodytes. DISCUSSION: On the one hand, the differences observed in the rib cross sections between H. sapiens and P. troglodytes might be related to different degrees of rib torsion and, consequently, to different thoracic 3D configurations. These findings can be functionally explained by considering their distinct modes of breathing and locomotion. On the other hand, although the rib cross sections belonging to Sts 14 are more similar to those of P. troglodytes, previous publications determined that their overall morphology is closer to modern humans. This discrepancy could reflect a diversity of post-cranial adaptations in Australopithecus.

Geometric morphometrics reveals restrictions on the shape of the female os coxae.

The methodology for sex determination in human skeletal remains depends on the different bone morphologies presented by men and women. Due to their direct implications in reproduction, the whole pelvis, particularly the os coxae, shows different characteristics in either sex. The sacrum and the os coxae constitute the birth canal. In this research study, the os coxae shape is analyzed using geometric morphometrics, providing information on morphology, regardless of size or any other factor beyond the geometry itself. A total of 46 adult ossa coxae from a Spanish archaeological collection were studied using geometric morphometrics. The results show that there is a restriction on the shape of female os coxae. In contrast, male os coxae presents a greater range of variation. The biological reason for this difference is the obstetrical dilemma; a concept defined as the anatomical conflict between bipedalism and the full-term birth of a neonate whose large head requires greater dimensions in the pelvic cavity. Our experimental data reinforce the validity of the obstetrical dilemma as source of the restriction on the shape of female ossa coxae. Additionally, according to the results obtained, size itself does not represent a condition for belonging to one sex or another.

Curvas percentilares de peso al nacimiento por edad gestacional para la población de la provincia de Catamarca (Argentina) / Weight for age perentile curves for the popultion of catamarca province (Argentina)

Introducción: La evaluación del desarrollo fetal y del peso al nacimiento es un objetivo prioritario en el ámbito de la epidemiología nutricional y de la salud pública. En la actualidad, la Organización Mundial de la Salud (OMS) no dispone de curvas específicas de peso al nacimiento para las distintas semanas gestacionales al considerar que las características socioeconómicas, ecológicas y étnicas de los distintos grupos humanos influyen en sus propios patrones de crecimiento. Objetivo: La presente investigación desarrolla las curvas percentilares de peso por edad gestacional para las poblaciones residentes en la provincia de Catamarca.Métodos: El procesamiento de los datos se llevó a cabo con el programa SPSS y para la posterior realización delas curvas percentilares se utilizó el programa LMS Chart Maker pro, a partir de un total de 22.576 nacimientos ocurridos entre 1994 y 2003. Discusión y conclusiones: Dichas curvas posibilitarán en el futuro una mejor valoración del desarrollo intrauterino y del peso de los recién nacidos en esta región delNoroeste de Argentina (AU)

Introduction: The assessment of fetal development and birth weight is a priority in the field of nutritional epidemiology and public health. Nowadays, the World Health Organization (WHO) does not have specific birth weight curves for the distinct gestational weeks considering that socio-economic, ecological and ethnic characteristics of the different human groups are found influencing their own growth patterns. Objective: This research develops centile curves for weight by gestational age concerning to resident populations in the province of Catamarca. Methods: In order to process data, SPSS statistical program was used, as well as LMS Chart Maker pro program for the subsequent performing of centile curves. The sample ascended to a total of 22,576 childbirths between 1994 and 2003. Discussion and Conclusion: In the future, these curves make possible a better assessment of intrauterine development and birth weight in this region of Northwest of Argentina (AU)

[Weight-for-age percentile curves for the population of Catamarca province (Argentina)]. / Curvas percentilares de peso al nacimiento por edad gestacional para la población de la provincia de Catamarca (Argentina).

INTRODUCTION: The assessment of fetal development and birth weight is a priority in the field of nutritional epidemiology and public health. Nowadays, the World Health Organization (WHO) does not have specific birth weight curves for the distinct gestational weeks considering that socio-economic, ecological and ethnic characteristics of the different human groups are found influencing their own growth patterns. OBJECTIVE: This research develops centile curves for weight by gestational age concerning to resident populations in the province of Catamarca. METHODS: In order to process data, SPSS statistical program was used, as well as LMS Chart Maker pro program for the subsequent performing of centile curves. The sample ascended to a total of 22,576 childbirths between 1994 and 2003. DISCUSSION AND CONCLUSION: In the future, these curves make possible a better assessment of intrauterine development and birth weight in this region of Northwest of Argentina.

Introducción: La evaluación del desarrollo fetal y del peso al nacimiento es un objetivo prioritario en el ámbito de la epidemiología nutricional y de la salud pública. En la actualidad, la Organización Mundial de la Salud (OMS) no dispone de curvas específicas de peso al nacimiento para las distintas semanas gestacionales al considerar que las características socioeconómicas, ecológicas y étnicas de los distintos grupos humanos influyen en sus propios patrones de crecimiento. Objetivo: La presente investigación desarrolla las curvas percentilares de peso por edad gestacional para las poblaciones residentes en la provincia de Catamarca. Métodos: El procesamiento de los datos se llevó a cabo con el programa SPSS y para la posterior realización de las curvas percentilares se utilizó el programa LMS Chart Maker pro, a partir de un total de 22.576 nacimientos ocurridos entre 1994 y 2003. Discusión y conclusiones: Dichas curvas posibilitarán en el futuro una mejor valoración del desarrollo intrauterino y del peso de los recién nacidos en esta región del Noroeste de Argentina.