Related Experiment Video
Updated: Jul 10, 2026
08:24
Sit-to-stand-and-walk from 120% Knee Height: A Novel Approach to Assess Dynamic Postural Control Independent of Lead-limb
Published on: August 30, 2016
Relative variation in human proximal and distal limb segment lengths
1Department of Anthropology, Tulane University, New Orleans, Louisiana 70118, USA. thollid@tulane.edu
American Journal of Physical Anthropology
|September 6, 2001
Summary
Human limb segment variation differs between proximal and distal bones. Distal limb segments, particularly the tibia, show greater relative variability within and between populations than proximal segments.
Area of Science:
- Human skeletal biology
- Anthropometry
- Evolutionary biology
Background:
- Understanding limb morphology variation is crucial for human evolution and adaptation studies.
- Proximal and distal limb segments may exhibit different patterns of variation due to developmental and functional factors.
Purpose of the Study:
- To investigate patterns of variation and covariation in human limb segment lengths.
- To test hypotheses regarding relative variability of proximal versus distal limb segments within and between populations.
- To explore the role of growth allometry in observed limb variation.
Main Methods:
- Analysis of variance-covariance matrices (VCMs) on logarithmically transformed limb segment lengths (humerus, radius, femur, tibia).
- Comparison of VCMs to theoretical matrices using an iterative procedure (Anderson, 1973).
- Examination of sex-specific differences in limb segment variability.
Main Results:
- Rejection of equal relative variance hypothesis; distal limb segments (radius, tibia) exhibit greater variability than proximal segments (humerus, femur).
- The tibia shows greater relative variability than the radius within males.
- Between-population analyses provide some support for the tibia being more variable, but do not exclude greater variability in both distal segments.
Conclusions:
- Relative variability of distal limb segments is greater than proximal segments within human populations.
- Differential growth allometry is a significant factor influencing limb segment variation within and between human populations.
- Observed patterns provide insights into human adaptation and evolutionary history.
Related Concept Videos
02:32Variation: Normal Distribution, Range, and Standard Deviation
In the field of psychology, there are several ways to organize measurements of a trait, feature, or characteristic (i.e., variables). Qualitative data, such as ethnicity, can be tabulated into a frequency count to provide information about the proportion, as well as the variety of groups in a sample or population. On the other hand, researchers can perform a wider set of calculations on quantitative data. The mean, mode, and median, for instance, are central tendency measures to identify a...
01:12Regional Terms
Regional terms describe anatomy by dividing the body parts into different regions that contain structures involved in contributing similar functions. Using these terms helps increase the accurate description and identification of the particular region of interest or region affected by the disease.
Primarily, the human body has two major regions, the axial and appendicular regions. The axial region comprises regions from the head to the abdomen and makes up the central body axis. In contrast,...
Primarily, the human body has two major regions, the axial and appendicular regions. The axial region comprises regions from the head to the abdomen and makes up the central body axis. In contrast,...
01:14Directional Terms
Directional terms are essential for describing the relative locations of different body structures. For instance, an anatomist might describe one band of tissue as "inferior to" another, or a physician might describe a tumor as "superficial to" a deeper body structure. These terms often use comparative terms in pairs to trace out the relative locations of one body part to another or descriptions of body tissues like the deeper ones from superficially present with reference to the body's upright...
01:15Bones of the Upper Limb: Ulna
The ulna and radius are parallel bones of the antebrachium or the forearm. The ulna lies medially and consists of a bony tip called the olecranon process at its proximal end. This hook-like projection articulates with the olecranon fossa of the humerus and forms the "hinged" ulnohumeral part of the elbow joint. This joint facilitates forearm extension and flexion while preventing its hyperextension. Similarly, the coronoid process, another bony projection on the proximal/anterior side of the...
01:09Bones of the Upper Limb: Radius
The radius is longer of the two bones that make up the human antebrachium or forearm. At the proximal end, the radius articulates with the capitulum of the humerus and the radial notch of the ulna to form the elbow joint. At the distal end, the radius articulates with the ulna via the ulnar notch, forming the distal radioulnar joint. Distally, the radius also attaches to the carpal wrist bones (scaphoid and lunate) to form the radiocarpal joint.
The radius has a nail-shaped head, and a short...
The radius has a nail-shaped head, and a short...
01:09Changes in the Appendicular Skeleton with Age
The upper and lower limb initially develops as a small bulge called a limb bud, which appears on the lateral side of the early embryo. The upper limb bud appears near the end of the fourth week of development, with the lower limb bud appearing shortly after.
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...