Human Body Size Research Articles

A reassessment of Bergmann's rule in modern humans.

It is widely accepted that modern humans conform to Bergmann's rule, which holds that body size in endothermic species will increase as temperature decreases. However, there are reasons to question the reliability of the findings on which this consensus is based. One of these is that the main studies that have reported that modern humans conform to Bergmann's rule have employed samples that contain a disproportionately large number of warm-climate and northern hemisphere groups. With this in mind, we used latitudinally-stratified and hemisphere-specific samples to re-assess the relationship between modern human body size and temperature. We found that when groups from north and south of the equator were analyzed together, Bergmann's rule was supported. However, when groups were separated by hemisphere, Bergmann's rule was only supported in the northern hemisphere. In the course of exploring these results further, we found that the difference between our northern and southern hemisphere subsamples is due to the limited latitudinal and temperature range in the latter subsample. Thus, our study suggests that modern humans do conform to Bergmann's rule but only when there are major differences in latitude and temperature among groups. Specifically, groups must span more than 50 degrees of latitude and/or more than 30°C for it to hold. This finding has important implications for work on regional variation in human body size and its relationship to temperature.

Study on Forklift Cockpit Design Based on Ergonomics

With the application of ergonomics in product design increasingly widely, humanization design of products has become a new revolution in the field of design. Based on the study of ergonomics, taking the forklift as an example, combined with the human body size data, operating characteristics and other factors, this paper analyzes the forklift cockpit human factors, such as the overall space layout, the human-machine interface design and the manipulation device arrangement, and proposes the concept of people-oriented forklift cockpit design. The research has taken an important step in this area of the modified forklift cockpit.

Design of Human Tracking Algorithm Based on Improved Camshift

Considering the problem of added background interference when initial target region is chose in Camshift tracking algorithm. This paper proposes a human tracking algorithm based on improved Camshift. The algorithm uses weight to determine the type of pixels in the back-projection, and then convert the back-projection into binary image, so as to improve the input accuracy of Camshift processing function. According to the human body size information, the algorithm appropriately improves the ratio of major axis and minor axis of search window, to optimize the output size of Camshift processing function. The contrast experiment proves the algorithm obviously improve accuracy and robustness of tracking effect.

Reference and Perception: Towards a Social Relativism Perspective

1. INTRODUCTIONSocial reference asserts the idea any reality exists in reference of another. Specifically, perception of a reality or interpretation of the reality is usually inferred from the reference of the actor.2 Although research in the reference concept may be relatively recent, the Chinese philosopher Zhuangzi (369-286 BC)3 described relativistic thought over 2000 years ago. Revitalizing this philosophical thought and bringing it up to date as one of the sociological perspectives through rigorous and empirical tests can be a contribution to Western developed sociological paradigms. Alike and different from such traditional perspectives as functionalism, conflict theory, symbolic interactionism, and exchange theory, etc., social reference theory can be another valid standpoint for viewing and interpreting the social world and human interaction.Relativistic thought is a major part of Zhuangzi's philosophy. One of his representative statements is Bi Yi Yi Shi Fei, Ci Yi Yi Shi Fef ((ProQuest: ... denotes non-USASCII text omitted.)), meaning that person has a different view of right or wrong from this person. We can interpret this line like this: There is nothing absolutely right or wrong, because different people have different views of the same social fact, and the different views are formed with different references. For example, raining is good and right for those people who have been experiencing tremendous drought, but bad and wrong for those already flooded. According to Zhuangzi and his relativism, nothing is absolute and everything is relative. Humans define size based on the human body size as its reference, although the space is indefinite to both ends (large and small). For example, a tree is to an ant is as a large island to a human being. Further, humans define time based on their life span as its reference, although time is indefinite. For example, one week to a butterfly may be as 1 00 years to a human being.In daily life, we are most unaware of our own referential mentality. Inasmuch as we are embedded in our culture, it is most of the time subconscious. Sherif and colleagues (1958) found when subjects first lifted a heavy weight, they underestimated the weight of lighter weights they were subsequently asked to lift. It seems no knowledge or feelings can be obtained without a reference, and the reference is usually the starting point of knowledge. Knowledge does not initiate in a vacuum.When you meet two other people, you are likely to compare each against the other on several dimensions to decide which you prefer. This may include physical beauty, similarity of interests and various personality factors. A simple physical way of illustrating perceptual contrast is to put one hand into hot water and other into cold water, then move them both to lukewarm water. The cold hand will feel hot and the hot hand will feel cold. To get someone to buy something expensive, first show them something even more expensive (Cialdini, 1993; Sherif, Taub, & Hovland, 1958). These experiments tell us when people make decisions, they tend to do it by contrasting between the decision item and reference items. When two things appear close to one another, we will tend to evaluate them against one another more than against a fixed standard, and they could happen most of the time subconsciously.The subconscious reference mentality is best illustrated via some visual perception experiments. As shown in Figure 1, the two light colored railroad ties are actually of the same length, but they appear to be unequal in the context of the railway in the perspective drawing. In Figure 2, the horizontal bar in the middle of the frame is actually of the same degree of the grey color throughout, but it looks like dark to the right and light to the left.The reference mentality can be consciously implemented. We often do comparative studies, in both natural and social sciences. …

Geographic variation in body form of prehistoric Jomon males in the Japanese archipelago: Its ecogeographic implications

Diversity of human body size and shape is often biogeographically interpreted in association with climatic conditions. According to Bergmann's and Allen's rules, populations in regions with a cold climate are expected to display an overall larger body and smaller/shorter extremities than those in warm/hot environments. In the present study, the skeletal limb size and proportions of prehistoric Jomon hunter-gatherers, who extensively inhabited subarctic to subtropical areas in the ancient Japanese archipelago, were examined to evaluate whether or not the inter-regional differences follow such ecogeographic patterns. Results showed that the Jomon intralimb proportions including relative distal limb lengths did not differ significantly among five regions from northern Hokkaido to the southern Okinawa Islands. This suggests a limited co-variability of the intralimb proportions with climate, particularly within genealogically close populations. In contrast, femoral head breadth (associated with body mass) and skeletal limb lengths were found to be significantly and positively correlated with latitude, suggesting a north-south geographical cline in the body size. This gradient therefore comprehensively conforms to Bergmann's rule, and may stem from multiple potential factors such as phylogenetic constraints, microevolutionary adaptation to climatic/geographic conditions during the Jomon period, and nutritional and physiological response during ontogeny. Specifically, the remarkably small-bodied Jomon in the Okinawa Islands can also be explained as an adjustment to subtropical and insular environments. Thus, the findings obtained in this study indicate that Jomon people, while maintaining fundamental intralimb proportions, displayed body size variation in concert with ambient surroundings.

Lessons from the life history of natural fertility societies on child growth and maturation

During the evolution of hominids, childhood and adolescence have been added as new life-history phases. The transition from infancy to childhood (ICT) confers a predictive adaptive response to energetic cues that strongly influence adult height, whereas the transition from juvenility to adolescence establishes longevity and the age of fertility. Evolutionary short-term adaptations to energy crises apparently use epigenetic mechanisms that defer the ICT, culminating in short stature. The study of hunter-gatherers gives us an indication of pre-demographic transition populations and their life style that prevailed for 99% of homo's evolution. The secular trend for receding age of pubertal development has been an adaptive response to positive environmental cues in terms of energy balance. In natural fertility preindustrial societies with limited access to modern contraception and health care, and whose economies are primarily subsistence-based, most resources are invested as somatic capital in human body size and fertility. Here we review results from databases for natural fertility societies, with the information on life history, population density, height and body mass, indices of adolescence and fertility. By using them it was possible to verify the ICT model as well as to explore pubertal parameters that are related to evolutionary fitness. They confirmed that body size was adaptively smaller in hostile environments, and was tightly associated with reproductive fitness.

Sizing up dogs

Sizing up dogs

Analysis on Lower Body Type of Korean Women in Their Early 20’s

The purpose of this study is to analyze lower body types of women and provide information of body improvement of Korean adult female clothing product to ready-made clothes companies. As for the method of this study, it was conducted to measure the parts of the lower body of adult women at the age from 19 to 24 years, to analyze their characteristics and to categorize body types. For study, it was measured 150 female women in Seoul. Data was analyzed by used SPSS/WIN 19.0 Program. The results of this study are as follows. The means of the subjects in their early 20s are 159.8cm in height, 67.0cm in waist circumference, 91.6cm in hip and 52.0kg in weight. As a result of comparison with the Korean's human body size on measurement data, 20 items out of 33 items showed significant difference. Factor analysis was executed for 66 body measure and calculation items to draw the body construction factors of the women's lower body in their early 20s and principal component analysis was performed by orthogonal varimax rotation to clarify the measurement of factors and to derive explanatory factors. As result of Cluster analysis, body types' characteristics divide into 3 types. Type1 has tall and fat body form, type2 has shortest and curvy body form and type3 has average height and the most skinny body form.

Compromised skeletal growth? Small body size and clinical contraction thresholds for the female pelvic canal

Small body size has been used in bioarchaeological contexts as an indicator of poor health and in clinical contexts as a risk factor for difficult childbirth, under the assumption that small size reflects compromised growth. Compromised growth in females may result in contracted pelvic dimensions and elevated risk of cephalopelvic disproportion. The basis for the use of clinical pelvic contracture thresholds for evaluating health and growth in skeletal populations is examined through comparisons of contracture frequencies and the relationships between pelvic canal size and body size in 11 skeletal samples (total n=195). The small-bodied samples show higher frequencies of contracted inlet and midplane posterior space dimensions. Canal breadth is correlated with femoral head diameter and bi-iliac breadth, but not femoral length. These results suggest that modern clinical standards do not take into account the variation in human body size and shape and the effect this variation may have on obstetric capacity without compromising obstetric function. It is problematic to use small pelvic dimensions, in the absence of evidence of death during childbirth, to infer compromised obstetric function resulting from biological stress, as is assuming that small size represents compromised skeletal growth.

Application Study of Wa Nationality Totem Symbol of Lincang in Modern Furniture Design

Today, the inheritance and protection of national culture become increasingly prominent. The findings can be seen that worship plays an important role in Wa nationality through the analysis of Cow Head and Wooden Drum in Wa’s totem worship. Combing with the design of specific cases and Wa’s totem worship, at the same time, extracted the national elements, furniture product design have been carried out. According to the aesthetic demand modern people and human body size scale, the design started which is not only good to realize national culture inheritance and protection, but also will push modern furniture design into the market. It is a good way to inherent and protect national culture, meanwhile, making a profit and reward.

AN EXPERIMENTAL STUDY TO GRASP THE PROFILE OF DISTRIBUTION OF PERSONAL OCCUPIED AREAS OF CROWD IN ROOM SPACE

In architectural planning, room space areas are mainly decided according to physical spaces such as human body sizes, occupant crowd densities, and the sizes of furnitures necessary for the room. However, human beings are also psychological entities and naturally require psychological spaces1), 2) as well. In former papers8) 12), we proposed a planning method of capacity and sizes of room under consideration to keep personal occupied areas. In this paper, we report the experimentally grasped distribution of allotted personal areas of occupant crowd to be used in the method, and the result of examination that the distribution can be approximated as Poisson distribution.

The Physiological Foundations of the Wealth of Nations

Evidence from economics, anthropology and biology testifies to a fundamental trade-off between the number of offspring (quantity) and amount of nutrition per child (quality). This leads to a theory of pre-industrial growth where body size as well as population size is endogenous. But when productive quality investments are undertaken the historical constancy of income per capita seems puzzling. Why didn't episodes of rising income instigate a virtuous circle of rising body size and productivity? To address this question we propose that societies are subject to a “physiological check”: if human body size rises, metabolic needs - our conceptualization of “subsistence requirements” - rise. This mechanism turns out to be instrumental in explaining why income growth does not take hold and societies remain near an endogenously determined subsistence boundary. When we use the theory to shed light on pre-industrial cross-country income differences we find that 60-70% of the income differences in 1500 can plausibly be accounted for by variations in subsistence requirements.

Climate history, human impacts and global body size of Carnivora (Mammalia: Eutheria) at multiple evolutionary scales

AbstractAim One of the longest recognized patterns in macroecology, Bergmann’s rule, describes the tendency for homeothermic animals to have larger body sizes in cooler climates than their phylogenetic relatives in warmer climates. Here we provide an integrative process‐based explanation for Bergmann’s rule at the global scale for the mammal order Carnivora.Location Global.Methods Our database comprises the body sizes of 209 species of extant terrestrial Carnivora, which were analysed using phylogenetic autocorrelation and phylogenetic eigenvector regression. The interspecific variation in body size was partitioned into phylogenetic (P) and specific (S) components, and mean P‐ and S‐components across species were correlated with environmental variables and human occupation both globally and for regions glaciated or not during the last Ice Age.Results Three‐quarters of the variation in body size can be explained by phylogenetic relationships among species, and the geographical pattern of mean values of the P‐component is the opposite of the pattern predicted by Bergmann’s rule. Partial regression revealed that at least 43% of global variation in the mean phylogenetic component is explained by current environmental factors. In contrast, the mean S‐component of body size shows large positive deviations from ancestors across the Holarctic, and negative deviations in southern South America, the Sahara Desert, and tropical Asia. There is a moderately strong relationship between the human footprint and body size in glaciated regions, explaining 19% of the variance of the mean P‐component. The relationship with the human footprint and the P‐component is much weaker in the rest of the world, and there is no relationship between human footprint and S‐component in any region.Main conclusions Bergmannian clines are stronger at higher latitudes in the Northern Hemisphere because of the continuous alternation of glacial–interglacial cycles throughout the late Pliocene and Pleistocene, which generated increased species turnover, differential colonization and more intense adaptive processes soon after glaciated areas became exposed. Our analyses provide a unified explanation for an adaptive Bergmann’s rule within species and for an interspecific trend towards larger body sizes in assemblages resulting from historical changes in climate and contemporary human impacts.

Month-of-birth effect on further body size in a pig model

Previous studies unanimously confirmed the existence of a dependence of human body size on the month of birth. The cause of the phenomenon has not been identified yet, although some possible causes were proposed e.g. seasonal changes of climatic and nutritional conditions. This study explored the issue in an animal model of 20,513 pigs. We found that body weights of 6-month-old pigs were the highest for subjects born in February, but for 2-month-old pigs the peak fell in May. Any statistical correlation between the month of birth and later body weight may be induced by (1) a long-term effect of the month of birth on further growth potential (LTE), or by (2) a short-term effect of seasonal factors differentiating the growth rate (STE), so we developed a mathematical method to separate the effects. The analysis proved that (1) the observed correlations resulted only from the STE, with May–June being the months of the highest growth tempo, and that (2) there was no significant LTE. The short-term effect was responsible for differences between patterns of weight for 2- and 6-month-old animals by the month of birth: since a pig monthly gain of weight increases with age, it is favorable for it to be born in February to attain the greatest weight at the age of 6 months, whereas 2-month-old piglets are heaviest when born a month or two before the May/June optimum for growth. The lack of a long-term effect of the month of birth on pigs’ weight supports the hypothesis of the cultural character of factor(s) responsible for the relationship between the month of birth and later body size in humans.

Life‐History Consequences of Density Dependence and the Evolution of Human Body Size

Previous attempts to explain variation in human growth and development emphasize the energetic constraints imposed by malnutrition and disease. However, this approach does not address the evolutionary effects of mortality risk on ontogenetic variation, a common theme in life‐history studies. The conventional approach can be reconciled with life‐history theory by considering the effect of mortality on the rates and timing of maturity in subsistence‐based human populations. Humans slow down growth and development and demonstrate smaller adult body sizes in high‐population‐density contexts, presumably because of increased nutritional constraints and disease loads. In addition, there is evidence of mortality‐based selection for relatively faster/earlier ontogeny in small‐bodied hunter‐gatherers living at high densities. This finding may be interpreted as an evolved reaction norm for earlier reproductive maturity and consequent smaller adult body size in high‐mortality regimes. In sum, comparative results support density‐dependent effects on body size that act through two pathways—nutritional constraints and juvenile mortality—at varying intensities, contributing to a nearly twofold range in body size across human societies.

Life-History Consequences of Density Dependence and the Evolution of Human Body Size

Life-History Consequences of Density Dependence and the Evolution of Human Body Size

Mutations in pericentrin cause Seckel syndrome with defective ATR-dependent DNA damage signaling.

Large brain size is one of the defining characteristics of modern humans. Seckel syndrome (MIM 210600), a disorder of markedly reduced brain and body size, is associated with defective ATR-dependent DNA damage signaling. Only a single hypomorphic mutation of ATR has been identified in this genetically heterogeneous condition. We now report that mutations in the gene encoding pericentrin (PCNT)--resulting in the loss of pericentrin from the centrosome, where it has key functions anchoring both structural and regulatory proteins--also cause Seckel syndrome. Furthermore, we find that cells of individuals with Seckel syndrome due to mutations in PCNT (PCNT-Seckel) have defects in ATR-dependent checkpoint signaling, providing the first evidence linking a structural centrosomal protein with DNA damage signaling. These findings also suggest that other known microcephaly genes implicated in either DNA repair responses or centrosomal function may act in common developmental pathways determining human brain and body size.

Life history trade-offs explain the evolution of human pygmies

Explanations for the evolution of human pygmies continue to be a matter of controversy, recently fuelled by the disagreements surrounding the interpretation of the fossil hominin Homo floresiensis. Traditional hypotheses assume that the small body size of human pygmies is an adaptation to special challenges, such as thermoregulation, locomotion in dense forests, or endurance against starvation. Here, we present an analysis of stature, growth, and individual fitness for a large population of Aeta and a smaller one of Batak from the Philippines and compare it with data on other pygmy groups accumulated by anthropologists for a century. The results challenge traditional explanations of human pygmy body size. We argue that human pygmy populations and adaptations evolved independently as the result of a life history tradeoff between the fertility benefits of larger body size against the costs of late growth cessation, under circumstances of significant young and adult mortality. Human pygmies do not appear to have evolved through positive selection for small stature-this was a by-product of selection for early onset of reproduction.

Overcoming high-field RF problems with non-magnetic Cartesian feedback transceivers

In extending human MR to field strengths approaching 10 T, the wavelength of electromagnetic radiation at the proton Larmor frequency becomes less than human body size and conventional radio-frequency coil circumference. Consequently, radio-frequency magnetic fields are better generated by an array of small coils than by one large coil. In this article, the primary problem of array coil interactions during transmission is examined, and a standard proposed whereby secondary induced currents should be less than 1% of the primary coil current. The use of cancellation methods and of power amplifiers with high output impedance to reduce interactions is examined in the light of this standard and found wanting. Non-magnetic Cartesian feedback transceivers functioning at the magnet entrance are then proposed as a solution that both reduces instrumentation cost and increases the bandwidth over which the standard may be met. The compromises inherent in instrument design are detailed and examples given of the innovative circuitry used. It is shown experimentally that when connected to interacting coils, two Cartesian feedback instruments function stably in accord with theory and such that the proposed standard is typically attained over a bandwidth of 22 kHz during transmission (much greater during signal reception)-enough for all current MR protocols.

Body size effect on brain volume in Korean youth

The relationship between human body size and brain size is still controversial, although brain size increases with body size across taxonomic levels. The magnetic resonance imaging volumetric analysis of the brain was performed in healthy 20-year old Koreans to investigate the effect of body size on brain volume. The whole brain volume was significantly correlated with body height in male (r=0.37, P<0.05) but not in female participants. The height effect on whole brain volume was increased considerably when data from both male and female participants were combined (r=0.57, P<0.05). The cerebellum volume was moderately correlated with body height in female (r=0.43, P<0.05) but not in male participants. The difference between sexes of the effect of body size on the brain needs to be investigated further.