Atlanto-axial joint Atlanto-axial joint The atlantoaxial joint is a joint in the upper part of the neck between the first and second cervical vertebrae; the atlas and axis. It is a pivot joint. The atlantoaxial joint is of a complicated nature. It consists of no fewer than four distinct joints. There is a pivot articulation between the odontoid process of the axis and the ring formed by the anterior arch and the transverse ligament of the atlas. There are three atlantoaxial joints: one median and two lateral: The ligaments connecting these bones are: The atlantoaxial joint in common terminology is actually a
Neoteny in humans body is indicated by glabrousness (hairless body). Neoteny of the genitals is marked by the absence of a baculum (penis bone); the presence of a hymen; and the forward-facing vagina. Neoteny in humans is further indicated by the limbs and body posture, with the limbs proportionately short compared to torso length; longer leg than arm length; the structure of the foot; and the upright stance. Humans also retain a plasticity of behavior that is generally found among animals only in the young. The emphasis on learned, rather than inherited, behavior requires the human brain to remain receptive much longer. These