Final answer:
The Dmanisi hominins were unique with small jaws and teeth, large third molars, a sagittal keel, and were fully bipedal with humanlike feet, differing from other early Homo species outside Africa.
Step-by-step explanation:
Characteristics of Dmanisi Hominins
The Dmanisi hominins showcase unique characteristics that differentiate them from other hominin species discovered outside of Africa. One notable feature is the small jaws and teeth, which contrasts with typically larger jaws found in other early hominid skulls. Moreover, the third molar, or wisdom tooth, is larger than the other molars, a trait also observed in Australopithecines and some early Homo species, but not common outside of the African context. In terms of cranial features, Dmanisi hominins had a skull shape reminiscent of Homo erectus or H. habilis, exhibiting a sagittal keel - a slight ridge along the top of the skull, which is characteristic of H. erectus.
When it comes to locomotion, Dmanisi hominins were bipedal and walked upright in a human-like manner, supported by humanlike feet with developed arches and ankles. These features underscore an advanced bipedal posture absent in other early hominins like H. floresiensis who did not have a humanlike gait and displayed a high stepping motion when walking.
Furthermore, early Homo species, such as Homo naledi, show a mix of primitive and advanced traits. Their legs and feet were almost identical to those of modern humans, suggesting a similar pattern of walking. Other factors that contribute to the distinction of hominins include brain size, dexterity of hands, and a reduction in bone mass in the skull and face. Despite their small brain size, hominins like H. floresiensis are not believed to have had reduced intelligence, challenging the convention that larger brain size is synonymous with higher cognitive abilities.