For billions of years, nothing moved. Single cells drifted in water. Those cells then combined to make squishy tadpole-like creatures. Suddenly, BAM! The Cambrian explosion takes place and the Earth is active and teeming with motion. With Life. A large variety of creatures appeared in all shapes and sizes. Most had one thing in common: an appendage that ran through the middle of their bodies.

A spine.

Thus marked the recorded history of our spine, the place from which we can track it’s development.

From Water to Land

It first appeared in water, with it’s benefit for swimming, able to change direction for balance. This beating tail, squishy flexible spine proved to be perfect in facilitating propulsive, forward motion, and strong enough to allow for sea life to cover vast distances, and eventually, reach land. Sea Life gave way to insects and amphibians, which gradually led to reptilian development. From there, the biological adaptation took a number of divergent paths creating a variety of animal classes. Life on land gave rise to mammals and a new challenge: the fight against gravity. As mammals adapted to their new environment, moving long distances on four legs generated a side-to-side motion resulting in the spine segmenting into three regions; the cervical, anterior dorsal, and posterior dorsal (1)

Increased demands of movement, including jumping and reaching, further decoupled the spinal column to create the upper and lower spine. The lumbar region was the last section to develop, evolving independently from the rest of the column allowing individual vertebrae to change and move without compromising the function of the entire spine.

As mammals grew in size, it became beneficial for ape-like creatures to develop a stiff spine for the demands of life in trees, to carry the weight of offspring on their back, while also swinging through branches. Increased protein consumption led to larger brain development, the formation of larger groups, and the creation of tools. Protein demands led to walking long distances to hunt larger animals. This was the tipping point for abandoning life in trees for good.

Lumbar Development

The spine then began to dismantle itself into smaller segments and made a 90 degree rotation, added that dignified “S” curve we recognize today to more effectively support walking, the developing torso, and increased weight of a growing head and brain. As life for early primates became more advanced and demanding, it led to increased effort (nomadism, hunting, gathering) and heavier loads to be carried, resulting in the birth of modern back pain.

“It’s the lumbar region that really allows mammals to do all sorts of different things,’… [yet] on the downside, the more recently evolved parts of the back – the lumbar region in particular – are also the source of most back pain”, writes Elizabeth Pannisi, a biology journalist for Science, in her article The evolotion of the spine fueled the rise of mammmals – and human back problems.

Through the evolutionary path of the human spine, the lumbar region is the newest innovation and the one that has gone through the most changes in the shortest amount of time; over hundreds of thousands of years rather than millions. That “S” shape of the lumbar is unique to evolution’s organic signature, it separates our abilities from other mammals – it makes us human. The lumbar allows us to enjoy and do many functions, yet sadly, it’s the part of our body we least care for. We don’t appreciate the lumbar’s value and we forget the spine’s fragility until we can no longer ignore the sudden pain from misalignment. It is then, flat on our back, that we realise how much we depend on it.

“Scientists showed how the very adaptations that have made humans so successful—such as upright walking and our big, complex brains—have been the result of constant remodeling of an ancient ape body plan that was originally used for life in the trees. This anatomy isn’t what you’d design from scratch”, stated Jeremy DeSilva of Boston University in the Science article: Human Evolution: Gain came With Pain

“Evolution works with duct tape and paper clips,” he expanded. “When humans stood upright, they took a spine that had evolved to be stiff for climbing and moving in trees, and rotated it 90 degrees to be vertical.”

Scientists and anthropologists are uncovering that evolution doesn’t “design” anything. Anthropologist Matt Cartmill of Boston University says, “It works slowly on the genes and traits it has on hand to jerry-rig animals and humans’ body plans to changing habits and demands”

 

Evolution doesn’t act to yield perfection, – it acts to yield function

– Matt Cartmill

If what research suggests is true, then in a sense, there is no ideal to which evolution is striving for. Evolutionary upgrades are only occurring as a response to yield a function our complex brains are asking of our bodies to do, and that is most often centered around our backs.

The spine, as we know it today, took the path of starting as a squishy organ to a rigid beating tail, to mineralizing and creating vertebrae, to becoming stiff and then decoupling for flexibility, finally rotating 90 degrees vertically to allow for walking upright. The evolution and the development of our spine is not a straight line, it was a complex path to create humanity.

Our conventional thinking that the evolution of vertebrates as a straight-forward progression to humanity has been misleading. In reality, we are discovering there is no defined path towards progress as we tend to think. There is no goal and no end point!

As the work days get longer, and the pace of daily life speeds up, the spine’s flexibility that allowed us to stand upright now faces a new challenge in the modern age: the need for constant repetitive bending centered around the lumbar region of the spine. Do you see the conflict? The spine is faced with two opposing functional requirements, the need to be flexible for repetitive bending and remaining stiff enough to carry weight while upright. These conflicting requirements has led to a unique problem in humans, resulting in an escalation in back pain. It’s an ongoing shift between stiff and pliable, which adds challenges and complexity to maintaining back and spine health.

Understanding these factors, we can recognize the challenges and functions that are unique to being human. New and modern stresses are changing our daily habits and the demands we place on our back and spine; meaning the need to evolve is upon us again, and we can’t wait another 500 million years for an upgrade.

Up next

Next we explore how the rise of civilization led to increased and unique demands on our spines, the ailments that accompanied progress, and how modern demands are imposing new stresses on our spine.

Read: Where things get sideways

UNDERSTANDING THE SPINE: A 3 PART STORY

PART 1

At Dorsum, we aim to free the world from back pain. This introduction to the brand outlines back pain in terms we can all understand.

The End of THE Spine

PART 2

To understand back pain, one must understand the complexity of our spinal evolution and how we got to where we are today.

EVOLUTION IS NOT A STRAIGHT LINE

PART 3

Advancements in civilization introduced new demands and stresses on the human spine. Agriculture introduced new challenges, and with them came pain.

WHERE THINGS GO SIDEWAYS