On Sunday, Egyptian authorities unveiled the completed restoration works on two colossal alabaster statues of a notable Egyptian king.
Located in Luxor, and standing over 30 feet tall, the two statues were destroyed in an earthquake 1,200 years ago, making their reconstitution an awfully long time coming.
Scientists usually study bones and muscle attachment points to understand how fossil hominins moved, but joint ligaments have received less focus. A new study in Scientific Reports shows that analyzing wrist ligament attachment areas can provide insights into hand use and locomotion across human evolution.
Led by Josep M. Potau and Aroa Casado from the University of Barcelona, the team used three-dimensional geometric morphometrics (3D GM) to study ligament insertion sites on the distal radius, the end of the forearm bone that connects to the wrist. They measured the size, orientation, and shape of the areas where wrist ligaments attach.
The results reveal variation in locomotor patterns among fossil hominins and clear differences between fossil species—such as Australopithecus afarensis, A. anamensis, A. sediba, Paranthropus robustus, Homo neanderthalensis, and archaic H. sapiens—and modern humans, chimpanzees, gorillas, and orangutans. Ligaments act as joint stabilizers and provide sensory feedback, and these differences in wrist anatomy reflect different uses of the hands: humans primarily manipulate objects, whereas non-human primates rely on arboreal and terrestrial locomotion.
The research builds comparative models of upper-limb ligament anatomy to estimate locomotion in fossil species. Unlike muscle attachment points, ligament insertions are often preserved on fossil distal radii, making them valuable for inferring locomotor behavior even when muscle features are absent. When ligament data matches muscle-based reconstructions, it reinforces interpretations; discrepancies may indicate alternative locomotor strategies.
The study found that Australopithecus afarensis, A. anamensis, and A. sediba have wrist ligament insertions resembling those of chimpanzees and orangutans, supporting a combination of habitual bipedal walking and tree climbing. Paranthropus robustus shows insertion patterns more similar to gorillas, suggesting a mix of bipedal, arboreal, and terrestrial behaviors.
For Homo neanderthalensis and archaic H. sapiens, the distal radius ligament insertions largely align with modern humans but include unique traits, such as a robust short radiolunate ligament area, likely reflecting greater wrist load from activities like hunting and tool-making.
The authors suggest that 3D analysis of ligament insertions can be applied to other species to study locomotor strategies and manual precision, providing a powerful tool for comparative anatomy, paleoanthropology, and understanding human evolution.Scientists usually study bones and muscle attachment points to understand how fossil hominins moved, but joint ligaments have received less focus. A new study in Scientific Reports shows that analyzing wrist ligament attachment areas can provide insights into hand use and locomotion across human evolution.
Led by Josep M. Potau and Aroa Casado from the University of Barcelona, the team used three-dimensional geometric morphometrics (3D GM) to study ligament insertion sites on the distal radius, the end of the forearm bone that connects to the wrist. They measured the size, orientation, and shape of the areas where wrist ligaments attach.
The results reveal variation in locomotor patterns among fossil hominins and clear differences between fossil species—such as Australopithecus afarensis, A. anamensis, A. sediba, Paranthropus robustus, Homo neanderthalensis, and archaic H. sapiens—and modern humans, chimpanzees, gorillas, and orangutans. Ligaments act as joint stabilizers and provide sensory feedback, and these differences in wrist anatomy reflect different uses of the hands: humans primarily manipulate objects, whereas non-human primates rely on arboreal and terrestrial locomotion.
The research builds comparative models of upper-limb ligament anatomy to estimate locomotion in fossil species. Unlike muscle attachment points, ligament insertions are often preserved on fossil distal radii, making them valuable for inferring locomotor behavior even when muscle features are absent. When ligament data matches muscle-based reconstructions, it reinforces interpretations; discrepancies may indicate alternative locomotor strategies.
The study found that Australopithecus afarensis, A. anamensis, and A. sediba have wrist ligament insertions resembling those of chimpanzees and orangutans, supporting a combination of habitual bipedal walking and tree climbing. Paranthropus robustus shows insertion patterns more similar to gorillas, suggesting a mix of bipedal, arboreal, and terrestrial behaviors.
For Homo neanderthalensis and archaic H. sapiens, the distal radius ligament insertions largely align with modern humans but include unique traits, such as a robust short radiolunate ligament area, likely reflecting greater wrist load from activities like hunting and tool-making.
The authors suggest that 3D analysis of ligament insertions can be applied to other species to study locomotor strategies and manual precision, providing a powerful tool for comparative anatomy, paleoanthropology, and understanding human evolution.
