Increased Human Energy Use Causes Biological Diversity Loss and Undermines Prospects for Sustainability

Abstract

Forum Earth has entered or soon will enter the sixth mass extinction of multicellular life (Wilson 1992(Wilson , 2002. Human activities are the primary reason. Many lines of evidence point toward this involvement, but here we consider a direct one. Our harnessing of energy sources other than our own has provided us with the means not only for creating modern civilization but also for taking a huge fraction of life's annual energy budget provided by plant photosynthesis. Vitousek and colleagues (1986) made the first detailed estimates of how much humans use, directly and indirectly, of the planetary energy budget: 27 percent of global net primary production (NPP) and 39 percent of terrestrial net primary production (tNPP). The flow of commercial energy, and the related confiscation of NPP, has an unavoidable negative effect on biodiversity. The loss of biodiversity in turn raises serious questions about the possibility of creating a durable global civilization.Perspective on the importance of energy flow is gained by comparing current energy flow with the prehistoric flow of energy through hunter-gatherer societies. When this is done, the current mass extinction appears as a predictable, expected result. Such a consequence provides sufficient justification for revising energy policies to reduce the amount and change the type of energy flow.

Megafauna biomass tradeoff as a driver of Quaternary and future extinctions

“…If biodiversity is actually a tradeoff between human biomass and other species' biomass, as both the QME and theoretical considerations indicate (13)(14)(15)(16), then depletion of fossil fuels without replacement by alternative energy sources would mean that a biomass crash is imminent, this one depleting human biomass and causing extinction in a wide spectrum of other species. Reliable projections on the number of years into the future that fossil fuels can sustain the global ecosystem at current levels vary, but generally are in the area of 50 more years for oil, 200 more years for natural gas, and 2,000 more years for coal (43).…”

“…Recognizing the tradeoff between human biomass, nonhuman megafauna biomass, and non-human biomass in general highlights the need for extraordinary efforts to conserve the world's remaining biodiversity (16). Business as usual will not stave off severe biodiversity losses.…”

“…1). Previous work has demonstrated that, as human biomass grows, the amount of solar energy and net primary productivity (NPP) available for use by other species shrinks, ultimately shrinking the amount of the world's biomass accounted for by those non-human species (13)(14)(15)(16). Therefore, growth of human biomass should be inversely related to biomass of other species in general and to other megafauna species in particular, given that large body size itself to a large extent depends on available NPP.…”

Incorporating the current sixth great mass extinction theme into evolution education, science education, and environmental education research and standards

“…A brief overview of past and present human activities associated with the current sixth great mass extinction Humanity has entered a sixth great mass extinction driven by our excessive activities (e.g., Alroy 2008;Jackson 2008;Lewis 2006;McDaniel and Borton 2002;Rockström et al 2009;Rohr et al 2008;Steffen et al 2007;Thomas et al 2004;Wake and Vredenburg 2008;Zalasiewicz et al 2010). These activities have taken many forms but the most devastating anthropogenic direct drivers affecting global biodiversity are: (1) habitat modification, fragmentation, and destruction; (2) pollution; (3) climate change; (4) overexploitation of species; and (5) the spread of invasive species and genes (Millennium Ecosystem Assessment MEA 2005; World Wide Fund for Nature WWF 2012).…”

Niche construction and Dreaming logic: aboriginal patch mosaic burning and varanid lizards ( Varanus gouldii ) in Australia

“…While there are many examples of negative effects, such as population depression, extinction and niche destruction [3,4]; positive effects, such as enhancing another species' population growth or constructing new niches to support a wider range of other species, are difficult to find. Yet humans, particularly hunter-gatherers, do have the potential to be significant 'ecosystem engineers [5]': organisms that physically modify the environment in ways that benefit other species as well as themselves [6 -8].…”