Birth mechanics in early hominins are often reconstructed based on cephalopelvic proportions, with little attention paid to neonatal shoulders. Here, we find that neonatal biacromial breadth can be estimated from adult clavicular length (R2 = 0.80) in primates. Using this relationship and clavicular length from adult Australopithecus afarensis, we estimate biacromial breadth in neonatal australopiths. Combined with neonatal head dimensions, we reconstruct birth in A. afarensis (A.L. 288-1 or Lucy) and find that the most likely mechanism of birth in this early hominin was a semi-rotational oblique birth in which the head engaged and passed through the inlet transversely, but then rotated so that the head and shoulders remained perpendicular and progressed through the midplane and outlet oblique to the main axis of the female pelvis. Any other mechanism of birth, including asynclitic birth, would have resulted in either the head or the shoulders orthogonal to the short anteroposterior dimension of the A.L. 288-1 pelvis, making birth untenable. There is a tight fit between the infant and all planes of the birth canal, perhaps suggesting a difficult labor in australopiths. However, the rotational birth mechanism of large-brained humans today was likely not characteristic of A. afarensis. Thus, the evolution of rotational birth, usually associated with encephalization, may have occurred in two stages: the first appeared with the origin of the australopiths with their platypelloid pelves adapted for bipedalism and their broad-shouldered neonates; the second which resulted in the modern mechanism of rotational birth may be associated with increasing brain size in the genus Homo. Anat Rec, 300:890-899, 2017. © 2017 Wiley Periodicals, Inc.

https://anatomypubs.onlinelibrary.wiley.com/doi/pdf/10.1002/ar.23573

Neonatal Shoulder Width Suggests a Semirotational, Oblique Birth Mechanism in Australopithecus afarensis.

Release of Bioactive Molecules Using Metal Complexes

An anthropometric study of 552 Tartu city and Tartu county recruits aged 17 years was carried out. Height and weight, 33 anthropometric measurements and 12 skinfolds were measured. Body fat percentage was assessed by Omron®BF 300 hand-held segmental body fat analyzer. From anthropometric measurements bone mass was derived by the Drinkwater et al. (1986) equation, and total skeletal muscle mass by the Lee et al. (2000) equation. The data were systematized into five height-weight SD-classes. There were 3 classes with harmony between height and weight class: 1 - small (small height and small weight), 2 - medium (medium height and medium weight), 3 - large (large height and large weight), 4 - weight class dominating (pyknomorphic) and 5 - height class dominating (leptomorphic). It was revealed that in classes 1, 2 and 3 the height and weight increase corresponded to the increase in all heights, breadths and depths, circumferences, skinfolds, body fat, muscle and bone mass. In class 4 circumferences, skinfolds, body fat and muscle mass were bigger. In class 5 all heights and the relative bone mass were bigger. The present investigation confirms the hypothesis that the five height-weight class system is applicable to seventeen-year-old recruits.

Five-class height-weight model for systematization of seventeen-year-old recruits' anthropometric data.

In September 1999 the author first visited Sardinia in order to participate in a meeting of the federative International Committee on Anatomical Terminology, organised by Professor Alessandro Riva. Our stay in Cagliari coincided with the 200th anniversary of the appointment of Francesco Antonio Boi as the first Professor of Anatomy at the University of Cagliari. After a small ceremony to mark this bi-centennial, we visited the Collection of Anatomical Waxes of Clemente Susini at the University. The fascinating history of this collection has been described in various publications (Zanobio, 1979; Cattaneo and Riva, 1993; Riva et al., 1997) and was further expounded by Professor Riva at the bi-centenary.

An afro-european and euro-african human pathway through Sardinia, with notes on humanity’s world-wide water traversals and proboscidean comparisons

Background. An anthropometric whole body model used in different Estonian studies of Kaarma and her co-workers since 1995 has proved to work in assessment of physical peculiarities of the body and its structure regularities in different age groups in both genders. Besides systematization of different body measurements, different authors suggested to use this classification in various applied studies, including medicine. Material and methods. The potential of using body height-weight standard deviation (SD) classification is shown through the example of adolescents (734 students: 352 boys and 382 girls) aged 12–15, who where studied in respect of their sexual maturation (according to suggestions of Tanner) as well as systolic and diastolic blood pressure (BP) (measured with mercury sphygmomanometer on the subject’s right arm in a sitting position). Anthropometric variables were measured according to the protocol recommended by the International Society for Advancement of Kinanthropometry (21). All the subjects were assigned into three height / weightconcordant and two height/weight-discordant categories according to the suggestions of Kaarma (11). Results. 1. Differences of the mean maturation signs and mean systolic and diastolic BP values between height-weight categories (HW-categories) were statistically significant for both boys and girls (p < 0.001). 2. In the same age group the mean of the signs studied increased from category I (small) to III (large), and discordant categories (pyknomorphous and leptomorphous) yielded the large category. 3. Sexual development of leptomorphous boys tend to be advanced in comparison with pyknomorphous boys, in girls it was vice versa: pyknomorphous were advanced compared to leptomorphous girls, though this difference was not statistically significant among all the sexual maturation signs. 4. The highest arterial blood pressure values were in the large category of both boys and girls. 5. Boys had elevated blood pressure values more often than girls of the same age group. Results of our study suggested monitoring adolescents of some heightweight categories more carefully, including children of height-weight discordant categories. Conclusion. The use of height-weight SD classification allows finding out whether the differences in the variables studied are related to the body build as a whole or not.

/pdf/bivariate-body-height-weight-classification-a-useful-tool-in-7fvxdq6o94.pdf

Bivariate body height-weight classification - a useful tool in systematization and analysis of medical data

The paper presents anthropometric data on 292 healthy neonates delivered of normal births at the Women's Hospital of Tartu University (150 boys and 142 girls). The parameters of the neonates' physical development measured included height, weight, sitting height, length of sternum and abdomen, shoulder width, upper and lower width and depth of thorax, width and depth of abdomen, D. cristarum, D. trochanterica, pelvic depth, 12 circumferences, foot length and two skinfolds (on abdomen and back). The mean weight of a neonate was 3620.5 g±448.7 g (minimum 2400 g and maximum 4854 g). Boys were somewhat heavier than girls (3684.7 g and 3551.3 g respectively). The average height of the infants was 49.9 cm±1.9 cm (minimum 44 cm and maximum 54.5 cm). Correlation analysis of the characteristics showed that body structure is a system of wellcorrelated anthropometric measurements where the leading role belongs to height and weight. The changes in the relation between height and weight (height-weight classification in 3×3SD classes) cause systemic changes in other measurements. Therefore, in further micropaediatric and clinical research, the height-weight classification could be used as the primary model of the body as a whole.

H. Kaarma

Papers

Body build structure of neonates