Axis (anatomy) The condition, where the dens is separated from the body of the axis, is called os odontoideum, and may cause nerve and circulation compression syndrome. On its anterior surface is an oval or nearly circular facet for articulation with that on the anterior arch of the atlas. On the back of the neck, and frequently extending on to its lateral surfaces, is a shallow groove for the transverse atlantal ligament which retains the process in position. The apex is pointed, and gives attachment to the apical odontoid ligament; below the apex the process is somewhat enlarged, and presents on either
Cold and heat adaptations in humans to that of Caucasians. This indicates the physiological adaptation of individuals that have left Africa for colder climates. During recent evolution (around 50,000 years ago), cold adaptation has selected for an increased metabolism and insulation (body fat). However, these traits cannot be effectively developed during a lifetime in cold conditions as selection takes place over many generations. Therefore, humans are forced to mainly rely on our behavioral and technological skills to live in and survive the cold . There are three types of cold the body is adapted to: extreme cold, moderate cold, and night cold. Extreme cold is characterized