To anyone reflecting on the last one-hundred-fifty years of biological research, it might seem strange to speak of the laws of life. The standard assertion in biology is that the living world can be explained only through the lens of evolution, an immensely complicated trajectory subject to myriad environments, chance events, and ecological contingencies. Yet beneath and beyond the frame of evolution, we observe lawlike patterns that pervade life. SFI researchers expand on evolutionary theory to discover life’s universal laws.

“Given the random nature of the evolutionary process that gave rise to all of [life’s] diversity, it might seem unlikely and counterintuitive that any regularity or systematic behavior would have emerged,” writes Geoffrey West, a physicist and SFI Distinguished Shannan Professor.

And yet…

In SFI’s research program, “Exploring Life’s Origins,” our scientists identify the chemical, dynamical, and metabolic processes that converge to generate life. We explore the patterns of spontaneous organization that appear when complex chemical systems transition from prebiotic chemistry to biology. We seek the universal patterns of life by studying how life might emerge in environments radically different from Earth’s. 

In the process of studying life’s origins, we work to understand better how the laws of physics, chemistry, and information make their way into the processes that shape life. As SFI Professor Chris Kempes explains, in the biological world, “mathematical and physical laws become biological laws.” SFI researchers synthesize work in theoretical and historical fields to distinguish contingent biological patterns from universal ones. 

SFI researchers contend, also, that looking to the emergence of life is not the only way to discover the laws of life. As SFI President David Krakauer argues, to discover the laws of life we must challenge standard definitions, seek out new principles, and reformulate how we understand biological entities.  To understand the laws of life, Krakauer argues, we must integrate life’s environmental scaffold into our thinking. In his words, “life is an ecological phenomenon, and if there's ever going to be a biological definition of life, it's going to have to be whole planet, and it's quite interesting if you look at a textbook on life, it never considers the ecological network.”

As SFI researchers have turned from conventional theoretical frames and looked to the large-scale patterns of how life unfurls, we’ve discovered a fascinating array of regularities. In our “Cities, Scaling, & Sustainability” project, we’ve derived a series of laws that appear as biological entities change in scale. The metabolic energy that living systems need to grow, for example, turns out to be reflected in a power law relationship that is consistent across biological systems. Scaling laws also show up in one of the primary life systems that human communities form: the city. In the “Social Reactors” project, SFI researchers look for the laws of settlements that cut across cultures and time. 

West says: “The existence of these remarkable regularities strongly suggests that there is a common conceptual framework underlying all of these very different highly complex phenomena.”

SFI researchers believe that life is not a static structure that inheres in individual organisms, but a process that emerges in time — even the individual is better understood as a verb. What of the ant without a colony? The microorganism without a biome? The bee without a hive? To understand life, therefore, we must also reformulate our understanding of laws: the laws of life, it turns out, are dynamic ones. The living world, it moves.

By building a catalogue of the laws that emerge in life’s diverse systems, SFI researchers compose the elements of a universal theory of life. While evolution is a spine of the study of life on Earth, a more universal theory of life will grant researchers better tools to understand life in systems distinct from the ones we know — systems that appear elsewhere in the universe, in the artifice of the lab, or in as-yet-unrecognized forms we have yet to discern. 


Further reading

Scale: The universal laws of growth, innovation, sustainability, and the pace of life in organisms, cities, economies, and companies 
Geoffrey West (Penguin Randomhouse, 2017)

A widely acclaimed book by SFI Distinguished Shannan Professor Geoffrey West, exploring the simple logarithmic scaling laws that govern life cycles in plants, animals, cities, and companies.

A General Model for the Origin of Allometric Scaling Laws in Biology
Geoffrey West, Jim Brown, Brian Enquist
Science volume 276, issue 5309 1997

The first paper advancing a general model for the ¾ power law for metabolic rates in organisms.

Growth, Innovation, and the Pace of Life in Cities
Geoffrey West, Luis Bettencourt, José Lobo, Dirk Helbing, Christian Künhert
PNAS 2007

Groundbreaking paper that explains two kinds of scaling laws seen in cities around the world—“sublinear” for systems that deliver resources and “superlinear” for socioeconomic quantities.

Predicting Maximum Tree Heights and Other Traits from Allometric Scaling and Resource Limitations
Christopher Kempes, Geoffrey West, Kelly Crowell, Michelle Girvan

A theory of plant architecture that uses a small set of common principles to derive the structure of individual branches, trees, whole forests, and “planetary-scale energy balance.”

The Origin and Nature of Life on Earth: The Emergence of the Fourth Geosphere
Eric Smith and Harold Morowitz (Cambridge University Press, 2016)

A book about life’s origins by two leading researchers in the field, which describes the emergence of life as “a cascade of successive phase transitions away from lifeless Earth” and takes ecosystems as the fundamental units of organization.

The information theory of individuality
David Krakauer, Nils Bertschinger, Eckehard Olbrich, Jessica Flack, Nihat Ay
Theory in Biosciences 2020

Paper that puts forth a novel theory of what makes an individual in biology at all levels of organization, from molecular to cultural.