1 Fire, environment, and society
To the best of our understanding, the Earth is the only planet which currently has an appropriate environment, atmosphere, and mix of resources which make fire possible. However, fire is much more than a naturally occurring chemical reaction. It is also a tool adapted by humans. Fire can modify environments and serve to shape social interactions between individuals, groups of humans, and the places in which they live. Therefore, fire can be understood as a distinctive property of the Earth and its current environmental conditions and as a defining characteristic of human social organisation and environment–society relationships.
Environmental historians, geologists, and geographers argue that over the past one million years, fire has been – and continues to be - key to environment-society relationships. They refer to the present era of the Earth’s history as the Anthropocene. This is the historical period dating from the commencement of significant human impact on the Earth, its atmosphere, ecosystems, and geology. Fire plays a very important role in defining the Anthropocene. Firstly, fire provided the layers of burned carbonised material (coal) in the geological layers of the Earth’s surface that humans have been able to use to create industrial power. Secondly, by burning carbonised material to make power, fire has changed the composition of the Earth’s atmosphere, introducing large quantities of gasses such as carbon dioxide (CO2) as the waste products of combustion.
Although definitions of the Anthropocene have largely focused on how humans have controlled fire for industrial purposes, this period has also been marked by an increase in wildfires and their intensity. For millions of years many plants and animals have taken advantage of naturally occurring wildfires, triggered for example by lightning strikes on dry vegetation, to forge unique ecological niches and reproductive cycles within complex ecosystems that come to depend on fire. However, as the environment changes as the result of human actions, wildfires are increasingly becoming an environmental challenge rather than an environmental opportunity. As populations increase and city suburbs extend further into savannah and semi-arid environments in places like California and parts of Australia, the danger of wildfires to human lifestyles is becoming an increasing source of public unease associated with climate change and urbanisation.
Therefore, all types of fire are deeply implicated in today’s major environmental issues. However, focusing on wildfires, this course will explore how they are caused by complex and indivisible environmental and social interactions and require equally complex responses.
Think of some of the ways humans have used fire to manage the environments in which they live.
How might human life be different without the ability to manage fire?
Humans have used fire both to manage the immediate environment and to make longer and more enduring changes to the environments in which they live. For example, to:
- keep warm during cold nights and cold seasons
- ward off wild animals, especially predators that threaten livestock or humans themselves
- cook plants and animals for food
- burn vegetation to clear ground and improve soil nutrient levels for agriculture
- to transform earth, rocks, and minerals into products such as lime for agriculture, pots for storage, bricks for building and metals for implements.
In terms of how human life might have been different without fire:
Firstly, without fire it is unlikely that humans would have been able to venture very far beyond the warm tropical savannah regions that nurtured early human populations. Rather than becoming a globally distributed species able to survive on every continent and at almost all latitudes, without fire humans would most likely have been confined to areas of the tropics where the climate is most favourable.
Secondly, without fire enabling humans to both enhance the nutritional value of food and the range of things that become edible with cooking, or the ability to preserve foodstuffs in storage vessels produced through firing, such as pottery, humans would most likely have had to continue to spend most for their time foraging for food. Increasing the range of things humans can eat by cooking and preservation has had a positive impact on human brain size because levels of nutrition are higher and more consistent. The ability to spend time doing things other than finding food has enabled humans to devote time to creating complex social and cultural formations.