Adaptation

Myths are beautiful.  The mixture of the real and the imagined create a sense of awe and wonder while the connection to reality keeps them tethered to the ground, making it difficult to see exactly where the ordinary ends the the extraordinary begin.  

Various classical authors relate the story of Milo of Croton, a man born sometime near the end of the 6th century BC known for his physical feats and athletic skill. According to some records, he was the wrestling champion in six Olympic Games and seven Pythian Games.  This is an athletic career of twenty-six years demonstrating not only his strength, but his durability as an athlete. Milo's career was twice as long as Russian wrestler Aleksandr Karelin who won three Olympic Golds in wrestling and was undefeated for 13 years during the late 80's and the 90's before losing to Rulon Gardner 0-1 in the 2000 Sydney games.  

It was said that Milo's training regiment included picking up a calf and carrying it around on his shoulders.  He would do this everyday for four years, picking up the calf and carrying it around on his shoulders.  Each day, the calf would get heavier, and each day, Milo would get stronger until he carried a four-year-old bull into the Olympic arena, killed it, roasted it and ate it in front of the amazed audience.  

Milo became synonyms with the idea of progressive overload training, or the principle of increasing a stimulus over time in order to promote adaptation and growth.  While the degree to which this adaptation occurred may be myth, the reality of the relationship between stimuli response and change is not.

It is a fundamental principal that increases in challenges are met with increases in capacity to meet those challenges.  The more difficult an experience, the higher the degree of change to meet a similar challenge in the future. That does not mean that change or growth is easy or without dangers.  In fact, it means just the opposite. Growth and development are inextricably connected to stressors, challenges and dangers.  These are not circumstances to be afraid of or to avoid completely, but circumstances that can temper and refine human capacity.  Aleksander Karelin had a mythical career in wrestling, Milo of Croton's feats of strength were told and retold for generations, and this history of humanity is teeming with stories of heroic displays, oftentimes unbelievable or extraordinary. 

If you want to step away from myth, and root your feet firmly on the bedrock of scientific evidence, you actually need to step foot into the water. Specifically, the Banda Sea near the Indonesian islands.  In between these islands, navigating the open waters, you will find members of the Bajau people, or as they have become known colloquially, the Sea Nomads.

For generations, the Bajau people have lived their lives mostly on the water in boats.  Some members of this group spend up to five hours a day underwater fishing and searching for food or other items.  While the Bajau are not recognized as belonging to any formal nation or government, they do come ashore to trade, work or bury their dead according to their religious practices, with most members claiming to be Sunni Muslim.

This extended period living on and in the water has piqued the interest of researchers who have studied the physiology of these Sea Nomads and discovered advantageous physical adaptations that aid in their aquatic lifestyles.  It has been reported some members of the Bajau people can dive to depths of over 200 feet and stay underwater for extended periods of time, with some reports of 13 minutes. In order to better manage the pressure of such depth, some of these divers intentionally puncture their own ear drums in order to mitigate the pain involved with increased underwater pressure.  

While the intentional practice of puncturing their ear drums helps with the discomfort of underwater diving, it is the enlarged spleens of the Bajau people that has drawn the interest of researchers around the world.  Research has shown that the spleens of these sea nomads to be larger than normal, providing a genetic advantage in hypoxic activities such as diving. Genetic markers have been isolated that seem to be related to this adaption within the population of these Sea Nomads. 

Within the spleen is a reserve of oxygenated blood.  A larger spleen contains a larger reserve which can be contracted to release oxygen rich blood into the blood stream allowing for a longer sustained period without external oxygen. Studies show that the spleens of the Bajau people can be up to 50% larger than average. Additionally, there is evidence of constriction in the blood vessels of their extremities allowing for increased oxygen to vital organs, another suspected genetic adaptation that may have been passed down from a subset of hominin ancestors known as the Denisovans which influences the level of carbon dioxide in the blood. 

Similar to Milo of Croton, these divers experience an increase in ability that is correlated with the demand of the activity in which they are participating.  For Milo, as the calf grew, so did his strength and capacity to carry it on his shoulders.  For the Bajau, as they dove for longer periods of time, their ability to store and prioritize oxygen usage increased as well.  Their physiology adapted to meet the increased demands of their environment and activity.  It was the degree of the challenge that determined the extent of the adaptation. 

The human capacity for adaptation is the cornerstone of our survival as a species. One particular adaptation, or a conglomeration of several adaptations is highlighted around the globe each year in the form of the 26.2 mile race known as the marathon. Sustaining a consistent running pace for extended distances has played a major role in our evolutionary success  Being able to walk and run upright, the effectiveness of sweating to keep our bodies cool, and a cardiovascular system which allows us to breath through our mouths while exerting ourselves is remarkably rare in the animal kingdom.  It is postulated that these advantages increased our success as hunters. 

Research by Utah biologist Dennis Bramble and Harvard University anthropologist Daniel Lieberman studied the fossil records of humanity's ancestors to identify specific physical traits such as tendons and ligaments in the feet and legs, specific musculature in the head and neck, and most notably, an upright frame which are specifically suited for long distance running. Biologist David Carrier theorizes that this series of traits is specifically suited early humans for "persistence hunting," or the longevity to chase down an animal until it exhausts itself or overheats.

Notably, this idea has prompted one of the most unique races in the world -- the Man vs. Horse Marathon, a 22-mile event that has pitted runners on foot against racers on horseback in Llanwrtyd Wells, Wales since 1980 after a local landlord organized the event to settle an argument in a local pub. The first runner on foot that was able to beat their equestrian counterpart was Huw Lobb in 2004, 24 years after the first event was run.   

While structural adaptations such as increased spleen size or elongated tendons occurs over generations, the ability to improve performance or learn a new skill can happen in a much smaller frame of time.  Simply running more often will increase vo2 max in a few weeks (the bodies capacity to absorb and use oxygen during exercise).  Weight training increases overall strength and muscular endurance, practicing meditation can have positive impacts on the brain and new skills are developed through practice over extended periods of time. It may not be as simple as picking up a growing calf each day, but the underlying principle is the same.   

The capacity for human development is correlated to the needs of the adaptation required to meet an uncomfortable or difficult challenge. Milo's strength increased daily because the weight of the calf increased daily.  The Bajau's people capacity for holding their breath expanded as they dove to deeper depths for longer periods of time.  It is the pushing against an obstacle that creates the pathway to overcoming it.  Pushing into the realm of what we cannot do yet is a requisite for growth.  Adaptations are the direct result of a higher demand and it is the series of steps between the ordinary and the extraordinary.