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Limb Proportions (limb + proportion)

Distribution by Scientific Domains

Life Sciences	100%

Selected Abstracts

Ecometrics: The traits that bind the past and present together

INTEGRATIVE ZOOLOGY (ELECTRONIC), Issue 2 2010
Jussi T. ERONEN
Abstract We outline here an approach for understanding the biology of climate change, one that integrates data at multiple spatial and temporal scales. Taxon-free trait analysis, or "ecometrics," is based on the idea that the distribution in a community of ecomorphological traits such as tooth structure, limb proportions, body mass, leaf shape, incubation temperature, claw shape, any aspect of anatomy or physiology can be measured across some subset of the organisms in a community. Regardless of temporal or spatial scale, traits are the means by which organisms interact with their environment, biotic and abiotic. Ecometrics measures these interactions by focusing on traits which are easily measurable, whose structure is closely related to their function, and whose function interacts directly with local environment. Ecometric trait distributions are thus a comparatively universal metric for exploring systems dynamics at all scales. The main challenge now is to move beyond investigating how future climate change will affect the distribution of organisms and how it will impact ecosystem services and to shift the perspective to ask how biotic systems interact with changing climate in general, and how climate change affects the interactions within and between the components of the whole biotic-physical system. We believe that it is possible to provide believable, quantitative answers to these questions. Because of this we have initiated an IUBS program iCCB (integrative Climate Change Biology). [source]

Vertebrate limb development and possible clues to diversity in limb form

JOURNAL OF MORPHOLOGY, Issue 1 2002
Cheryll Tickle
Abstract Chick embryos are good models for vertebrate development. The principles that underlie chick wing development have been discovered and there is increasing knowledge about the molecules involved. The importance of identifying molecules is that this provides a direct link to understanding the genetic basis of diversity in form. Chick wing development will be compared with limb development in other vertebrates. Possible mechanisms that could lead to variations in form, including limb reductions and limblessness, differences between fore- and hindlimbs, limb proportions, and interdigital webbing can be suggested. J. Morphol. 252:29,37, 2002. © 2002 Wiley-Liss, Inc. [source]

Life history and locomotion in Cebus capucinus and Alouatta palliata

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2009
Michelle Bezanson
Abstract As an individual matures from birth to adulthood, many factors may influence the positional repertoire. The biological and behavioral changes that accompany a growing individual are expected to influence foraging strategy, social status and interaction, diet, predator avoidance strategies, and ultimately positional behavior as a behavioral link between anatomy and the environment. In this work, positional behavior is considered as an important feature of life history in juvenile and adult white-faced capuchins (Cebus capucinus) and mantled howling monkeys (Alouatta palliata) inhabiting the same tropical forest in Costa Rica. During growth and development ontogenetic changes in body size, limb proportions, and motor skills are likely to influence locomotion and posture through the arboreal canopy. I collected data on positional behavior, activity, branch size, branch angle, and crown location during a 12-month period at Estación Biológica La Suerte in northeastern Costa Rica. Life history timing and differences in rates of growth did not predictably influence the development of adultlike positional behaviors in Cebus and Alouatta. Young Cebus resembled the adult pattern of positional behavior by 6 months of age while howlers exhibited significant differences in several positional behavior categories through 24 months of age. The positional repertoire of both species revealed similarities in the types of modes used during feed/forage and travel in juveniles and adults. Data presented here suggest that the environment exerts different pressures on growing Cebus and Alouatta that may relate to diet, energy expenditure, foraging skill, and/or social learning. Am J Phys Anthropol, 2009 © 2009 Wiley-Liss, Inc. [source]

Patterns of positional behavior in mixed-species troops of Callimico goeldii, Saguinus labiatus, and Saguinus fuscicollis in northwestern Brazil

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 1 2001
P.A. Garber
Abstract We present the results of a 4-month field investigation of positional behavior, vertical ranging, and species differences in limb proportions and body mass in a mixed-species troop of Saguinus fuscicollis, Saguinus labiatus, and Callimico goeldii in northwestern Brazil. Despite certain similarities in overall positional repertoire, patterns of positional behavior varied significantly between species. Travel in Callimico occurred principally in the lowest levels of the canopy, and was characterized by an exaggerated form of hindlimb-dominated bounding (bounding-hop), and leaping to and from vertical trunks (55.1% of leaps). In contrast, saddle-back tamarins traveled in the lower and middle levels of the canopy, and engaged in a range of leaping behaviors, including stationary leaps (37.3%), acrobatic leaps (31.3%), and trunk-to-trunk leaps (20%). Red-bellied tamarins exploited the highest levels of the arboreal canopy. Travel in this species was dominated by quadrupedal bounding and acrobatic leaps (67% of leaps) that began and ended on thin, flexible supports. Species differences in positional behavior correlated with species differences in limb proportions and locomotor anatomy, and provide a framework for understanding niche partitioning in mixed-species troops of Saguinus and Callimico. Am. J. Primatol. 54:17,31, 2001. © 2001 Wiley-Liss, Inc. [source]

Body frame dimensions are related to obesity and fatness: Lean trunk size, skinfolds, and body mass index

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2010
Maciej Henneberg
We explore relationships between BMI and skinfolds and anthropometric variables reflecting variation in lean body frame. Data on the middle class adult Australian women (n = 1260) collected in 2002 during a National Body Size and Shape Survey were used. Standard measurements of stature, weight, skeletal dimensions (shoulder width, hip width, chest width, and depth, limb lengths), circumferences of head, trunk, limbs and triceps, subscapular and abdominal skinfolds were taken. Techniques for measurements of skeletal frame minimized the inclusion of adipose tissue thickness. Analysis of variance and parametric and nonparametric correlations were used. Vertical dimensions show weak correlations with fatness, while body frame circumferences and transverse dimensions are consistently, significantly, and substantially correlated with fatness, each explaining from 3 to 44% of variation in skinfold thickness. Skeletal dimensions explain up to 50% of variation in skinfold thickness (multiple regression). Especially high correlations with skinfold thickness occur for chest width, depth, and hip width (r range from 0.42 to 0.66). Body frame dimensions reflect largely trunk volume and the trunk/limb proportions. Larger lean trunk size is associated with greater fatness. Since the size of the abdominal cavity, and thus the gastrointestinal system (GI), is reflected in the trunk size, we speculate that larger frame may predispose to obesity in two ways: (1) larger stomachs require greater bulk of food to produce feeling of satiety as mediated through antral distension, (2) larger GIs may absorb more nutrients. Frame size may help to detect the risk of obesity among young adults. Am. J. Hum. Biol. 2010. © 2009 Wiley-Liss, Inc. [source]