Nature uses many consistent principles that allow life forms to thrive. The embryo in-utero undergoes mirroring of the macro process of biological evolution. For example, the human foetus continues to exhibit features that we have knowingly evolved away from such as gills and flippers. Many millions of years ago when single celled organisms were swimming around in the priomordial oceans, these organisms began to develop responsiveness to their environments. Their shape began to change to make it easier for them to move and to find nutrients. These little creatures were called Pseudopods. Later, these organisms developed a central nervous system and we began to see the beginning of brains. These structures required a structure of armour to protect the spinal cord, but also needed to be able to articulate from side to side to enable movement. The spine is one of natures most beautiful creations, and perfectly balances two of yoga philosphy’s most important concepts: sthira (stablility) and sukha (good space).
The first sea creatures had spines which undulated laterally to enable movement. As we moved out of the water to land, amphibians still moved their spines laterally (just think of the way that snakes move). As limbs evolved out of the sides of the body they enabled more effective slithering but didn’t really offer the body a great deal of support. The major evolutionary step happened when limbs became more important to offer the body support. From a survival standpoint, animals can see better as quadrupeds, and spot food and prey from greater distances. We began to see the respiratory system descend into the protective casing of the ribcage, and the head and sensory apparatus moved upwards creating the cervical curve of the neck. As creatures began to jump up onto hind legs, the rear legs became the main apparatus for locomotion, and the forelimbs developed into skilled tools for manipulation. As animals began to walk on hind legs the lumbar curve became necessary as a means of distributing the weight more evenly along the spinal column.
Interestingly, chimpanzees do not have a lumbar (lower back) curve as they are primarily quadrupeds, who can only spend a limited amount of time upright. The human spine is unique amongst mammals as it exhibits both primary and secondary curves in order to evenly distribute weight when standing. However, as the only true bipeds on the planet, we are not very mechanically stable creatures. We have the highest centre of gravity, the smallest base of support, and the biggest and heaviest brains. It’s quite remarkable that we can walk at all! In fact, he only way we are able to work out how to make all of this work to our advantage is the fact that we have a big brain!
Embryo in the Womb PoseOur primary curve in the womb is the the C shaped kyphotic curve that runs through down the back of the rib cage, behind the lungs. This remains our primary curve once we are born. We have postures in our yoga vocabulary which mimic this primal movement patterns. Childs Pose (Balasana) mimics this C shaped curve of the spine, as does Embryo in the Womb Pose (Garbha Pindasana seen here on the right). Practicing these postures with awareness and intelligence of where they comes from helps us to connect with our embryonic wisdom.
The cervical curvature of the neck only becomes apparent only as we tilt our heads backwards to make our way through the birth canal and take our first breath. Our first postural task as human beings comes from learning to stabilise the weight of our heads. This is assisted by infants first intuitive responses to life outside the womb. Co-ordinating the muscles required for sucking, and enabling the movement of the lungs as we breathe and cry, all assist to strengthen the muscles of the neck. When we make it to an upright position (around the age of one) we still have no lumbar curve, hence our unsteadiness on our feet. In fact it takes us almost 10 years to fully develop our lumbar curve at the base of our spine.
I remember observing this process with utter fascination. In just one short year my children evolved from helpless little blobs who couldn’t hold up their heads, to sitting alone, to crawling and slithering on the floor all the way to that first triumphant unsupported step. This for me was such a huge lesson in yoga and evolution, as the macrocosmic process of evolution was replayed in fast forward right before my eyes.