Earth: A changing planet of life
Change happens. In a dynamic world, this has always been true. Over many aeons, climates have changed, varieties of life have come and gone, and all living systems have evolved. These monumental transformations characteristic of physical reality find their continual drive in complex phenomena, from age-old solar cycles to the habits of terrestrial creatures (e.g. from bacteria to beavers) — to other possible forces which may yet lay beyond our understanding. Every life form impacts the system in which it lives and of which it is an inseparable part. Change is, perhaps, the only constant of the natural world.
Throughout our existence, human beings – as members of the animal world – have also always influenced change. Pushed by the urge to survive and thrive, human activity has reflected its myriad cultures in re-sculpted landscapes, interrupted natural processes and in the creation of new ecological patterns all over the Planet. The depth of ecological change has varied from culture to culture, with notable societies far more intense than others in their utilization of and impact on the Earth’s bounty. From the Ancient Romans to the indigenous peoples of the Aleutian Islands, numerous societies throughout history have pushed up against physical limits of their local biological systems, causing a slow in their growth or a search for new landscapes from which to fulfill communal needs.
Warning signs: what has happened
It is the pace and depth of change over roughly the past two centuries, and particularly over the most recent several decades, that has astoned those who reflect on this remarkable break from past patterns. Seldom has this Planet Earth seen such a widespread, radical and expeditious transformation of the natural world due to a single variety of life. In recent decades, expanding environmental consciousness and concern for the natural world has been effective in documenting examples of “runaway” change. The WWF’s 2012 Living Planet Report is one such comprehensive snapshot. To name merely a few of the many highlights:
- Only a third of rivers in the world greater than 1000 km in length remain free-flowing and without dams on their main channel.
- The acidity of world oceans has increased by 30% since the Industrial Revolution.
- Global biodiversity health has declined by 30% since 1970, with the greatest decline seen in freshwater species and tropical regions.
- Varieties of life which have been crucial to the survival and cultural identity of human populations, such as the Northern bluefin tuna, are now in danger of extinction.
- Many of the forest systems, rivers, grasslands, oceans, watersheds, flora and fauna upon which we and all other life forms depend are in a state of profound alteration.
Although decline in biodiversity is the global norm, there are some examples of species making a positive comeback in places like the United States. An analysis of 110 endangered species in the US found that 90% are currently on track to meet their recovery goals, including gray wolves in the north Rocky Mountains and California condors. However, the same cannot be said around the Planet due to a complex combination of anthropogenic factors.
Notably, global climate change increasingly appears to be a troubling reality, significantly spurred on by the burning of fossil fuels. Both greenhouse gas emissions and the concentration of warming gases in the atmosphere have been rising since the Industrial Revolution; by the 1950s, the atmospheric concentration had risen from pre-industrial levels to the highest level in at least 800,000 years. We have begun to note the initial effects on long-term weather systems, especially in the Earth’s polar regions.
Analyses such as the Living Planet Report tend to formalize two sobering conclusions:
1. Biodiversity has declined, and is declining, all over the Planet.
2. The demand by the human population as a whole has exceeded the Planet’s supply – and ever-increasingly so.
In the early 1970’s, humanity’s global ecological footprint passed a mark indicating what one Earth could sustain in terms of resource use. On average as a species, we are currently using 50% more resources than the Planet can provide. This means that it takes 1.5 years for the Earth to regenerate the resources that people utilize in one year. Put simply, our human population is in a state of “overshoot”. There is now no question that on average, present human development is physically unsustainable. It is also worthy to note that, in contrast, the historical and current activities of highly industrialized societies have placed the largest burden on natural systems.
With the realization that Planet has physical limits to what activities it can support, we are now faced with the question, how are we to continue to live on Planet Earth?
Changes in living
Change is not restricted to so-called natural systems. All human societies also change over time – in practices, territories, and systems of organization. Clearly, each and every society changes at its own pace; and the pace of change for any society is not universally static.
However, just as we see the pace of change throughout many of the Earth’s living systems increase as we move toward the present day, so too do we see a recent acceleration of change in human history – especially visible in societies yielding now-global influence.
This rapid pace of global social change wasn’t always so. According to historian Clive Ponting, previous human patterns of life and survival remained roughly unchanged for 99% percent of human history. For nearly two million years, humans obtained their means of survival from gathering foodstuffs and hunting animals, drawing on a deep knowledge of their local areas and tools (mostly derived from stones) fitted to their function. With this nutritionally adequate diet, this range of lifestyles allowed the human species to gradually spread out over nearly every part of the world. Typical life for most of human existence was mobile and closely connected to the flow of the seasons and the migration of wildlife; belongings and food storage were kept to a minimum; and communities consisted of small groups of 25-50 people. It took nearly two million years to reach a population of only about 4 million people worldwide – roughly the current population of the city of Montreal, Quebec.
It is only in the most recent 40,000 years do we begin to find evidence of more profound change. Artifacts from certain locations suggest the proliferation of new forms of tools crafted from a far wider array of materials. Contrary to popular belief, hunters and gatherers did indeed have an impact on their local living systems, particularly when their hunting activities revolved around one species (e.g. bison) to the exclusion of others. Overall, because of persistently low and thinly-spread populations, and in some cases embedded cultural practices in place to restrict overhunting, the global impact of these communities was small.
Many of these time-tested ways of life would eventually meet startling new methods of obtaining sustenance from the living world. Starting about 10,000 years ago, in the space of a few thousand years “a radical different way of life emerged based on a major alteration to natural ecosystems in order to produce crops and provide pasture for animals” (Ponting). Through marginal changes, the world had entered the revolutionary era of agriculture. While some societies retained their traditional forms of life, for others agriculture delivered the power to harness the land according to human desires. Fuelled by this newfound bounty of food production and storage, cities and powerful political bodies began to emerge. By 1200 CE, the worldwide population had reached 200 million and then rose sharply to 550 million by 1600. The world’s population at long last reached one billion in about 1825.
In the past two centuries leading up to the modern day, daily life for some societies “changed more than it had in the 7,000 years before” (Mokyr). In Western Europe, revolutions in science, industry and commerce released enormous transformations upon largely pastoral societies. Whereas people had predominantly lived in quiet rural areas, they now lived mostly in noisy, polluted urban areas, removed from the forests and the fields of smaller communities. Most personal household items were now machine-made, leading to the positioning of consumption as a dominant purpose in life. With powerful developments in medicine and sanitation, the death rate and infant mortality rate in these regions began to drop.
Thus we come to the present day. Due to globalization (the spread of the capitalist economic system) under the moniker of “development”, the pace of change in human societies has arguably never been higher.
- New technologies are pushed out with greater frequency than ever. Currently, the average American child spends on average more than seven hours a day interacting with an online world through a digital screen. Reduced direct contact between children with the natural world is reported all of the world (e.g. Ethiopia).
- Cultural change is afoot: UNESCO estimates that nearly half of the world’s languages will disappear by the end of the century.
- Health is now better everywhere in the world today and income is much higher in most countries than it was in 1800. However, the income and health gaps between countries are larger today than 200 years ago. More than half of the human population lives in poverty and at least one fifth are severely undernourished.
- In 2008, for the first time in human history, more than half of all people live in towns and cities than not. Our finite world has shot past a once unthinkable benchmark: 7 billion people and counting.
Change has always been a fact of human life. Change itself is neutral — open to our own subjective judgements of good and bad. Yet in the present day change seems to have grown to a breakneck pace. And again we face the question: Given our current tragetory of change, how are we to continue to live on Planet Earth?