Emergent Bioengineering

Our planet is experiencing an accelerated process of change associated with a variety of anthropogenic phenomena. The future of this transformation is uncertain, but there is general agreement about its negative unfolding, which might threaten our own survival. Furthermore, the pace of expected changes is likely to be abrupt: catastrophic shifts might be the most probable outcome of this ongoing, apparently slow process. Although different strategies for geoengineering the planet have been advanced, none seem likely to safely revert the large-scale problems associated with carbon dioxide accumulation or ecosystem degradation.

An alternative possibility is inspired by the rapidly growing potential for engineering living systems. It would involve designing synthetic organisms capable of reproducing and expanding to large geographic scales with the goal of achieving a long-term or transient restoration of ecosystem-level homeostasis. Such a regional or even planetary-scale engineering would have to deal with the complexity of our biosphere. It requires not only a proper design of organisms but also understanding their place within ecological networks and their evolvability. This is the domain of what we call emergent bioengineering: the use of synthetic biology as a tool to design, build and deploy living systems that interact with existing ecological communities to restore, augment or redirect their dynamics.

We are exploring this problem using mathematical, computational and experimental approaches. Several classes of "Terraformation motifs" are being studied. These include engineering mutualistic dependencies between synthetic and resident species — a plant or another microbe — where the synthetic organism is designed to be host-dependent while enhancing the survival and spread of its host. In a different scheme, the synthetic species would survive attached to, and perhaps degrading, a human-produced substrate such as plastic debris. A further design involves organisms that operate in wastelands or sewage, confined to habitats of no profit to humans. In all cases, the designed mutualistic interactions act as effective firewalls against undesired evolutionary processes.

A crucial application involves arid and semiarid ecosystems. These drylands cover around 45% of emerged lands and host more than one-third of the human population, and they are expanding under the pressure of global warming. We have shown that the dynamics of these systems exhibit bistability: two different vegetated states can coexist under identical environmental conditions, and tipping points between them are mediated by the soil microbiome — particularly the biological soil crust. Using models that couple vegetation dynamics with microbial communities, we study how synthetic interventions based on engineered cyanobacteria or other soil microorganisms could prevent the catastrophic green-to-desert transition and improve moisture retention, carbon sequestration and nitrogen fixation.

This programme requires the integration of ideas from currently weakly connected domains, including synthetic biology, ecological and genome engineering, evolutionary theory, climate science, biogeography and invasion ecology. It is a likely future scenario that will demand not only new science but also careful ethical and biosafety considerations.

References

Emergent Bioengineering
V Maull, Y Shpilkina, V de Lorenzo, R Solé
Current Opinion in Biotechnology, in press (2026)

Synthetic Horizontal Gene Transfer for Ecosystem Restoration
V Maull, G Aguadé-Gorgorió, V de Lorenzo, R Solé (2025)
bioRxiv, 2025.09. 23.678013

Synthetic ecosystems: from the test tube to the biosphere
R Solé, V Maull, DR Amor, JP Mauri, CP Núria (2024)
ACS Synthetic Biology 13 (12), 3812-3826

Biodiversity as a firewall to engineered microbiomes for Restoration and Conservation
V Maull, R Sole (2024)
Phil. Trans. R Soc. B 11, 231526

Network-level containment of single-species bioengineering
V Maull, R Solé  (2022)
Philosophical Transactions of the Royal Society B: Biological Sciences 15, 377

Ecological firewalls for synthetic biology
B Vidiella, R Solé (2022)
Iscience 25 (7)

Ecological complexity and the biosphere: the next 30 years
R Solé, S Levin (2022)
Philosophical Transactions of the Royal Society B: Biological Sciences 377;20210377

Synthetic soil crusts against green-desert transitions: a spatial model
B Vidiella, J Sardanyés, RV Solé (2020)
Royal Society open science 7 (8)

Synthetic biology for terraformation lessons from mars, earth, and the microbiome
N Conde-Pueyo, B Vidiella, J Sardanyés, M Berdugo, FT Maestre, R Solé (2020)
life 10 (2), 14