Sacrum lumbar vertebra, and its lower part with the coccyx (tailbone) via the sacral and coccygeal cornua. The sacrum has three different surfaces which are shaped to accommodate surrounding pelvic structures. Overall it is concave (curved upon itself). The base of the sacrum, the broadest and uppermost part, is tilted forward as the sacral promontory internally. The central part is curved outward toward the posterior, allowing greater room for the pelvic cavity. In all other quadrupedal vertebrates, the pelvic vertebrae undergo a similar developmental process to form a sacrum in the adult, even while the bony tail (caudal) vertebrae remain unfused.
History of beliefs about the human body Yang Qi energy where as a female has dominant Yin energy. Transgenderism, hermaphroditism and other variations of the body can be explained by the Yin and Yang Qi ideas of the body much better than the European counterparts. Other types of change in the world were classified by Wood, Fire, Earth, Metal and Water. Applied to the body these 5 forces were the Liver, Heart, Spleen, Lung, and Kidney. These representations of the physical world in the body was understood dynamically and represents a deeper connection to the non animate objects and surroundings of a human. The body was not