A savior to miners.
John Scott Haldane, a Scottish born Physiologist, specialized in research of the respiratory system. Most notably, he specialized in research on the physiology of gases and the role they played in the human body. Among his many findings and accomplishments are the relationships between carbon dioxide in respiration, the effects of carbon monoxide on miners the identification of chemical weapons and the invention of gas masks during World War I, and the development of decompression chambers for deep sea diving; often experimenting upon himself to increase his understanding of how gases interacted within the blood stream.
It was Haldane who suggested the use of canaries in mines to detect for poisonous gases. Canaries, like other birds that require high amounts of oxygen intake to fly at higher elevations, have a much more efficient system for taking oxygen into their lungs. Because their respiratory system also consists of several air sacs, they take in more oxygen per breath than humans, and in this sense sensitive to the introduction of poisonous gases than humans.
Until the mid 1980's, canaries were still used in coal mines as an early detection system for the buildup of carbon monoxide and other toxic gases. Carried in cages, and sometimes treated as pets, these birds were the litmus test for air quality in mines. Because of their sensitivity to changes in the environment, canaries became the archetype of the sentinel species. Sentinel species are animals and organisms that indicate harmful changes in the environment for humans because they are more susceptible specific environmental changes and conditions with a habitat.
There have been several documented examples of sentinel species such as the dancing cats of Minamata, Japan who displayed symptoms of mercury poisoning before their human counterparts fell victim to pollution of their local marine food source, or the eventual banning of DDT in 1972 after the decline in bald eagles in areas where these pesticides were being used. Some species, notably muscles and other bivalves accumulate exponentially more chemical concentrations than other species inhabiting the same areas and serve as harbingers of unhealthy ecosystems.
While these species are highly susceptible to changes in the environment, humans are adaptation machines and have evolved to thrive in a wide variety of climates and environments. Research in neuroplasticity indicates that our brains are capable of adaptation at the chemical, structural, and functional levels in order to meet the challenges of an incredible complex and changing world. With this cognitive advantage, mankind has set itself apart from the rest of the ecological world as the most adaptable species on the planet.
The double-edged sword of our ability to adjust to changes in the environment is that we are dull to the subtle changes that happen over time. We do not notice the changes in the natural world around us because it does not have the same impact on our physiology as it has on another species more vulnerable to alterations in the environment in which they live. Our ability to transport food or water from one area to another mitigate the negative effects of a drought. Our ability to heat or cool our homes decrease our sensitivity to changes in temperature. Our sensitivity to minor changes has weakened as our ability to adapt has improved.
in essence, when there is an imperative to adapt, we have been much more likely to make changes to the environment around than to change ourselves. While most organisms evolve to survive, we alter our surroundings to suit our needs. Much like a person who moves from the mild weather of the Pacific Northwest to the heat of the desert in Arizona, the first inclination is to stay inside and turn up the air conditioning unit to avoid the somewhat painful process of acclimation.
The power that human beings have accumulated over time, the ability to modify mother nature herself, has given us an advantage over every other species on the planet. We will continue to make changes to the world until we are forced to adapt to to massive global and environmental changes. The human species will survive, but what that survival will eventually look like is still to be determined.
The trajectory that we are on is not sustainable, nor is it without its consequences. Eventually, human beings will be forced to change in some way in order to survive, and it is only when survival is on the line that any organism makes significant and lasting changes. Penguins have evolved streamlined bodies and features that make them incredibly agile underwater. On land, they are clumsy at best. The reason they have adapted to be such adept swimmers is because of the dangers beneath the water's surface. The predators most likely to hunt down and feed on penguins are under the water, and are little to no threat on land. The dangers, and ultimately the need to change, are much more prevalent while swimming, so penguins can afford be clumsy on the surface, but it would be a death-sentence underwater. So while we can ignore the canary in the corner, we will eventually have to acknowledge the elephant in the room; especially as it continues to grow. We will most certainly adapt and change, but will it be on our own terms in order to avoid potential threats, or will it be in order to survive a much harsher and more dangerous world?
