Biologie synthétique et conservation de la biodiversité : de quelle manière façonneront-elles la nature de demain ?
Humans have always sought to reshape nature to meet their needs. Beginning with the control of fire and the domestication of plants and animals through to massive water diversion schemes, the development of nitrogen fertilizers and the planting of extensive monocultures, this shaping and reshaping of nature has become an essential part of being human. Humans have now reached an apogee: we are responsible for driving species to extinction at rates that far exceed background rates in the geological past; on average, humans appropriate about 25 percent of potential net primary terrestrial productivity, mostly from agricultural land use and harvests; we use over half of all accessible fresh water; we apply more nitrogen fertilizer than is fixed naturally in all terrestrial ecosystems; and humans are changing the atmosphere through the dramatically increased production of methane and carbon dioxide.
A growing understanding of such pervasive human influence on natural systems has resulted in a proposal to name the current epoch the Anthropocene. This proposed epoch began around the year 1800 with the onset of industrialization. It is suggested that since then, as a result of continual expansion and growth in human populations and their collective impact on the natural environment and living systems at all scales, there may be an impending abrupt and irreversible state shift in the earth’s biosphere. Whether or not this happens, it is clear that humans have already become the dominant ecological and evolutionary force on the planet.
The Anthropocene epoch is characterized by not only the extent of human alteration of nature but also the development of concern for its conservation throughout the 20th century in the form of increasingly systematic attempts to protect species and ecosystems. However, despite decades of effort and hundreds of millions of dollars, the conservation community has not been successful in preventing depletion of biodiversity. Much has been achieved, and there have been local successes. Well-focused projects have been successful at reversing declines of particular species and habitats. However, at a global level, governments and conservation organizations have failed to achieve internationally agreed-upon goals to reduce the rate of biodiversity loss.
Much of the past human impact on the biosphere has been a result of growth in human endeavours such as commercial fishing and industrial agriculture, as well as their indirect impacts, such as growth in industrial waste and the associated release of long-lasting chemicals into the environment. Human impact on the biosphere is now realized in increasingly novel ways, with humans breaching boundaries between species, creating novel forms and functions, and integrating the living and the nonliving. These are some of the new creations:
- cyborg insects
- robotic fish that swim with real fish
- artificial trees to absorb atmospheric carbon and even achieve artificial photosynthesis
- machines harnessed to the human brain
- nanobots equipped with bacteria inserted into the human body to fight disease
The development of powerful technologies has allowed humans to achieve some of these ends through the purposeful manipulation of DNA itself, giving rise to the field of synthetic biology. Though there is no agreed-upon definition of synthetic biology, all framing concepts emphasize scientific design or engineering, a focus on putative human benefit and a somewhat soft insistence on the creation of novel life forms.
The field is moving fast, with billions of dollars invested globally, and novel applications or improvements of existing ones emerging weekly. As a result, there is much to discuss. Is synthetic biology to be feared by conservationists, interpreted as a final assault on the diversity of the natural world? Or will it provide them with solutions to known threats to biodiversity, such as the fungal diseases that threaten many amphibians and bats with extinction? Are conservationists ignorant Luddites who advocate “naturalness” for no more reason than a general feeling of comfort with the status quo? Wild species and ecosystems are a vital source of genetic raw material for synthetic biologists: does that give the industry an interest in preserving wild species and ecosystems faced with extinction? If the purpose of synthetic biology is to create intelligible and predictable living systems, then synthetic biologists might share with conservation biologists a concern for the possible consequences of unwinding natural complexity.
Humans have long sought to improve their control over organisms. Agriculture, including plant and animal breeding, served this end for much of human history. An understanding of physical inheritance, then genes and eventually molecular biology has put humans on a path to set the growth and behaviour of plants, animals and microbes to serve human ends.
Aviation provides a useful analogy. Humans have always marvelled at, and sought to explain, how birds stay aloft and how they accomplish such wonderful feats of acrobatics and endurance. Yet we are not restricted to studying only evolved systems in our efforts to understand or employ the principles of flight. Indeed, humans have primarily made progress in understanding the principles of flight through constructing and testing artificial systems.
Nevertheless, there is still no definitive mathematical description of how geese fly. Nor is there a goose anywhere built from aluminum or carbon fibre capable of carrying hundreds of humans over thousands of miles, powered by jet turbines with blades that move at nearly the speed of sound. Despite our continued ignorance of the detailed mechanisms of bird flight, we quite successfully build and rely on aircraft that display behaviours we can understand and predict. This, of course, is the very definition of engineering.
In less than a century, humans progressed from vaguely controlled flight in rudimentary hang-gliders to the Boeing 777. This aircraft was designed and tested entirely in silicon before the first 777 airframe was, in effect, printed out via computer-aided manufacturing and then flown by a test pilot. The combination of predictive design, powerful test and measurement capabilities, and the ability to build exactly what is designed underlie many of the technologies we rely on every day. This includes not just airplanes, but computers and communications, automobiles, power generation and, in many cases, the shoes on our feet.
For the majority of its practitioners, synthetic biology is no less than the application of these same engineering principles to living systems. It may seem a distant dream indeed to build biological systems with behaviours as predictable and well-defined as a Boeing 777’s, but it is a dream that a great many synthetic biologists share, and there is already substantial progress toward realizing it. To set the context for these efforts, consider that humans have been modifying biology through artificial selection for many millennia. Within the last few decades, humans have refined these skills by learning to explicitly move genes from one organism another, a technology usually referred to as recombinant DNA. This technology is a remarkable demonstration of human ingenuity, and it also has provided tangible and substantial economic benefits.
Since the establishment of formal conservation organizations at the end of the 19th century, the most important conservation strategy has been the creation of protected areas to separate humans from other species. The idea of controlling access to particular pieces of land for nature or for particular species (e.g., designating sacred groves, gardens or hunting reserves) is ancient and cuts across cultures. Internationally, this approach drew on the model of game or hunting reserves (e.g., in Europe and European colonial territories such as those in Africa); on the American idea of national parks as pristine or wilderness areas; and on the British notion of smaller and more managed nature reserves.
But despite local successes, conservationists have not been succeeding in their objective of conserving greater biodiversity. Numerous measures have been applied to quantify this lack of success, and a general air of despair has settled over the field. In the last few years there have been strong voices demanding a new approach to conservation, called by some the “modernist movement,” one that particularly incorporates human well-being into the goals of conservation. Debate rages around this topic and about the need to change the approach, the methods and the values of conservation.
However, little of this debate has addressed two of the most dramatic technologies that are being developed: geo-engineering and synthetic biology. These two are not equivalent in the stage of their development or their discussion. Concern over the reality of climate change and its impact on humanity and the rest of the natural world is driving the discussion about climate-related geo-engineering: a deliberate intervention in the planetary environment of a nature and scale intended to counteract anthropogenic climate change and its impacts.
Synthetic biology is much further along in its development and testing than geo-engineering. Its very development raises the following key issues for conservation:
- Extinction may not be forever. There are ongoing attempts to recreate endangered species using the tools of synthetic biology. If successful, would such species be regarded as representatives of the species to which extinct forebears belonged? Or would they be viewed as “invasives from the past” and a threat to existing species? How would choices be made about which species to save? More fundamentally, what conservation value would these forms have if the habitats that once supported them are gone? Might we face the moral hazard whereby confidence in our ability to recreate extinct species undermines our willingness to conserve naturally occurring biodiversity?
- Synthetic life evolves. How will synthetic organisms interact with existing species and how far will such interactions be predictable from current ecological understanding of interspecific interactions? Will they become invasive and damage existing communities, or might they be safe and useful in restoring degraded or polluted ecosystems, or might they even address other ecological problems that have been intractable to date? Who will regulate the release of synthetic organisms outside the contained laboratory: will the permissive regulatory environment of “garage biology” be widely endorsed, will national governments try to establish individual regimes, and how will local and international views on the matter be taken into account?
- Our various definitions of “natural” will no longer be fit for purpose. Much of conservation is based on conserving ecosystems developed through ecological and evolutionary processes over the course of time, sometimes reflecting tight sets of interlinkages that are hard to restore once lost. Will interactions between synthetic and natural organisms arise easily, or might the very different origins lead to largely disruptive impacts on natural communities? What would be the change to public perceptions of what is “natural” and the notion of evolution as a process beyond human construction? Will these technologies challenge the ethical basis for conservation action, as they have done in other settings?
- Nature’s services can be synthesized.The value of an ecosystem to society is increasingly central to arguments about the importance of biodiversity. One of the most common promises of synthetic biology is to engineer organisms that generate services of benefit to people (e.g., carbon sequestration, pollution control). What impact will this have on the relative value attached to natural ecosystems that already deliver these ecosystem services?
- Synthetic life delivers private benefits. Many forms of life being developed by synthetic biology are being patented. The benefits provided by these organisms will reflect the economic interests of those able to invest in and develop them. This may well favour applications in existing industrial processes and commodity chains (energy, agriculture, aquaculture) and the operations of large business corporations. Impacts on the wider environment will tend to be treated as an externality. Corresponding impacts on price and other economic changes for smaller producers (e.g., smallholder farmers) will affect their decisions about land conversion and management, and hence future patterns of biodiversity loss. How will a balance be struck between private risk and gain versus public benefit and safety?
Conservationists may choose to ignore synthetic biology, but they do so at their own risk and the risk of the biodiversity they are devoted to conserving. Synthetic biology is a fact, and the fact that it is being pursued throughout the globe by governments, industries, academics and individuals means that it will be with us for a long time. Promises of a future in which synthetic biology has solved all of humanity’s major problems jostle with promises of a future in which synthetic biology has exacerbated the injustices and environmental damages. But hype and exaggerated claims are counterproductive to developing adaptive and ethically sound regulatory models responsive to stakeholder concerns.
In order to operate and to prosper, synthetic biology must engage with the larger society and secure societal permission from regulators and from the public. This engagement with ethicists, anthropologists, the policy and advocacy communities, and the larger scientific communities has typified synthetic biology in the United States and Europe. The British public is increasingly aware of synthetic biology and its potential benefits and drawbacks, and in general it shows conditional support with concerns about control, who benefits, health and environmental impacts, and misuses and governance. Most Americans support moving forward with the science but are concerned about the creation of biological weapons, the moral implications of synthetic biology and the negative health implications; they are to a lesser extent concerned about environmental damage. Support is highly contingent on how the public thinks the science will be used.
There is a serious need for wider discussion of the relationship between synthetic biology and biodiversity conservation and what choices society can and could make. But this discussion will be difficult, for two reasons. First, synthetic biology is a technical field little understood by nonexperts. It will be difficult to create conditions for representative groups from society to engage in a well-informed, structured and balanced discussion.
Second, the discussions are hard to frame because it is difficult to identify the right counterfactuals or alternative futures to compare with those underpinned by the new technology. It seems inevitable that synthetic biology will be a major factor in affecting the future. But that future world will not be a slightly older version of the world that we currently inhabit. Rather, it will have a significantly altered climate, changed sea levels, novel pests and diseases, nonanalog ecological communities and a human population with changed priorities.
The discussion between conservation and synthetic biology must be based not on alarmist or triumphalist positions but on a clear-eyed examination of the norms, oversight, and public education necessary to make decisions about the enormous power of altering life on earth. Such a careful, respectful public discussion must examine the continuing role of conservation values. Much of conservation as currently practised is predicated on the core ideals of wilderness and nature, though other practices envisage a carefully managed planet with all the biological components in place – albeit carefully tended by conscientious (human) custodians. Synthetic biologists propose to further equip humans to actively and consciously engineer the living world. The transformed world of 2050 will demand new strategies and new approaches in conservation. Synthetic biology can and should be incorporated into these as a powerful new tool to face the powerful new challenges facing conservation.
Kent H. Redford is principal at Archipelago Consulting; William Adams is at the University of Cambridge, UK; Georgina Mace is at University College London, UK; Rob Carlson is principal at Biodesic; Steve Sanderson was CEO and president of the Wildlife Conservation Society; and Steve Aldrich is principal at bio-era. This article is adapted from “How Will Synthetic Biology and Conservation Shape the Future of Nature?” Framing paper prepared for a meeting between synthetic biology and conservation professionals for Clare College, Cambridge, UK, April 9-11, 2013. All the references can be consulted in the original article.