The environmental crisis has never loomed so large nor been so extensively debated as in the last few years. But at the same time we have never heard less about environmental ethics - the bio-inclusive perspective that insists on moral consideration not only for humankind but for the legions of other species who share the planet with us.
It is assumed the survival of humanity itself is ultimately dependent on the ecological integrity of the biosphere and therefore that no special pleading is required for ecosystems or other species in their own right.
But is this assumption correct? While the biosphere does currently provide essential life support for human civilisation, it is not inconceivable that we might in due course devise artificial systems that mimic the functionality of ecological systems, making natural ecologies superfluous.
Exemplified in solar cities that photosynthesise and industrial aggregates that cycle water and carbon, such “genetic architecture” would be sensitive to context and co-adaptive and in that sense as sustainable as the natural systems on which it was modelled. There is no reason in principle why an entire global urban-industrial formation should not ultimately usurp the biosphere altogether, replacing it with a “new nature" designed by humans exclusively for humans.
Such a post-ecological civilisation might perhaps retain teams of “service species”, whose only purpose would be to satisfy human needs and wants, while all other species would prove dispensable in favour of artificial systems that mimicked the life support currently supplied by the biosphere.
If the fate of non-human species is in our hands, and we can survive perfectly well without (most of) them, then our decision whether or not to conserve them is indeed a moral one: would it be wrong for us to replace the living biosphere with artificial systems of our own?
Presumably most of us would consider this wrong. But why? It is not considered wrong in modern societies to kill or displace organisms on a vast scale to sustain and service humanity. Indeed, biocide, in the sense of the mass destruction of living things, is the very premise of the process of development that is in full swing across the globe.
Habitat is routinely destroyed, environments contaminated, wildlife stripped from the oceans for human consumption and slaughtered on land for trivial human ends while domestic animals are enslaved and tortured in factory farms. “Pest” creatures like bacteria, cockroaches and fungus are happily put to the sword. Biophobia is the foundation of contemporary civilisation.
So if the mass destruction of (non-human) life is considered morally acceptable, why would we baulk at the more wholesale destruction of the biosphere?
The intuition that runs through public debate in this connection seems to be that we do have a moral obligation to life, but not to individual living things: we may destroy organisms and communities and populations with impunity provided we do not in the process extinguish entire species or forms of life.
This de facto though usually implicit environmental ethic enters public discourse through the scientific category of biodiversity. Biodiversity functions in public and policy discourse not merely descriptively but also prescriptively: it is treated not only as a fact of ecology but a value to be protected.
The coherence of such an ethic of biodiversity may be questioned on two counts, the first moral, the second, ecological.
If living things are not considered morally entitled to protection in their own right, as our acceptance of biocide implies, then why should species matter? True, a diversity of species is necessary for a healthy biosphere; but if the biosphere turns out to be relatively expendable for human purposes, and we don’t value living things in the first place, then we have no reason to conserve species.
From the viewpoint of an ethic of biodiversity, the ethical trigger for environmental intervention is species endangerment: we are ethically called to intervene to prevent extinction. But taken to its logical conclusion, this makes little ecological sense. For if nothing is protected until it becomes endangered, then only remnants and “last things” will eventually remain. Viable ecologies cannot be constituted out of such remnants: attrition will inevitably occur. Ecology is premised on abundance: tens of thousands of seeds are produced to replace a single organism; huge populations are required as buffers against environmental set-backs and contingencies. At the individual level, organisms may indeed compete for scarce resources, but at the population level, plenitude is the rule: nature operates with large numbers.
If we are ethically committed to saving the biosphere then, we cannot depend on an ethic of biodiversity. Biophobia must be renounced and an ethic of respect for life in general embraced. Instead of continuing to put pressure on the biosphere, stopping short only at the point of endangerment of species, we should be seeking to optimise the populations of all species, including our own, relative only to the internal constraints imposed by the checks and balances inherent in ecosystems.
Ecological optimisation of the human population would entail dramatic reduction, since our present population has been achieved at massive cost to other populations. This reduction would not be a matter merely of numbers however, but of offsetting the ecological costs of human activity against any positive inputs that a technologically reformed civilization might make into global ecology.
A viable environmental ethic based on the optimisation of species-populations would lead to a question modern society has so far failed to ask, the question of proportionality: how much human presence is enough? How much is compatible not merely with preservation of species but with abundance of populations?
If we are to save the biosphere we need to acknowledge that the biosphere requires ethical consideration in its own right, and that a mere ethic of biodiversity will not do the job. An adequate environmental ethic will rest on a generalised respect for life that will give rise to a principle of bio-proportionality - the ecological optimisation of populations. Anything less than this will only undermine the prospects for nonhuman life on earth by masking or colluding with a lethal biophobia.