Addy Pross, Professor Emeritus of Chemistry at Ben-Gurion University and author of "What Is Life? How Chemistry Becomes Biology," discusses dynamic kinetic stability as a key to understanding life's origins. He challenges traditional physics notions, emphasizing the importance of energy and adaptability in biological systems. Through fascinating analogies, he illustrates how living organisms maintain stability despite constant change. Pross also explores the intricate relationship between metabolism, replication, and the evolution of consciousness, prompting listeners to rethink life's complexity.
Dynamic kinetic stability challenges traditional views by showing that living systems maintain stability through continuous energy intake and renewal rather than minimizing energy.
Redefining life as a replicating chemical system in a dynamically kinetically stable state offers a fresh perspective on life's origins and complexity.
The link between energy dependence and evolution highlights that continuous energy input is essential for sustaining complex biological systems and preventing entropy.
Deep dives
The Nature of Dynamic Kinetic Stability
Dynamic kinetic stability (DKS) differs from traditional notions of stability, where systems minimize energy and settle into low-energy states. In contrast, DKS refers to systems that remain stable over time through continuous renewal and external resource intake, allowing them to maintain their structure while undergoing substantial internal change. This concept challenges the idea that stability is solely associated with low energy, emphasizing that life sustains complexity through a balance of energetic renewal and persistent self-organization. Understanding DKS is crucial for recognizing how early life may have originated, as it provides a framework to discuss the dynamic processes necessary for living systems.
Redefining Life's Definition
The definition of life is complex, with hundreds of varying perspectives contributing to confusion about what constitutes living systems. Traditional definitions often focus on biological processes like replication and metabolism or physical principles such as organization and stability. However, an emerging perspective suggests that life can be viewed as a replicating chemical system in a dynamically kinetically stable state, thereby presenting a novel recipe for understanding life. This new framework enhances the understanding of life's origins by integrating chemical dynamics with the replicative capabilities of molecules.
The Evolutionary Path: From Simple to Complex
Life evolves not merely through replication but through the progressive complexity of living systems as they adapt to their environments. The once dominant RNA world theory, which proposed that self-replicating RNA molecules led to complexity, faced challenges, particularly as simpler molecules replicated more efficiently. Dynamic kinetic stability introduces the possibility that early life forms, exhibiting replication and evolving toward complexity, could outcompete simpler counterparts, allowing for a more robust evolutionary process. This understanding bridges the gap between foundational chemical processes and the emergence of complex life forms.
Impact of Energy on Life's Organization
A key aspect of dynamic kinetic stability is the persistent dependence on energy and resources for sustaining organized systems. Energy fuels the processes that allow systems to inhibit entropy and maintain structure, indicating that life is inherently non-equilibrium. When energy input ceases, systems revert to equilibrium and disorder, highlighting the role of energy as vital for not just life, but the ongoing evolution of complex organisms. This principle reinforces that as long as energy is available, biological systems can harness it to maintain their dynamic state and evolve.
Consciousness and Cognition as Evolutionary Tools
The discussion of consciousness reveals that awareness and cognitive capabilities may exist even at the microbial level, leading to a spectrum of cognitive functions across different life forms. The notion that earlier life forms possessed primitive self-awareness lays a foundation for understanding the evolution of more complex consciousness in advanced organisms. Such cognitive elements are not isolated but linked to environmental interactions crucial for survival, indicating that cognition aids persistence within ecosystems. This expanding perspective invites exploration into how cognitive abilities emerged alongside life’s evolutionary path, contributing to adaptability and survival in varying environments.
Erwin Schrödinger said that the important characteristic of life is that it "goes on doing something... for a much longer period than we would expect an inanimate piece of matter to keep going under similar circumstances." Living organisms are in constant motion inside; so where does this stability and persistence come from? Addy Pross points to a novel kind of chemical phenomenon -- "dynamic kinetic stability" (DKS), a feature that enables a chemical "fountain" to persist in the presence of an energy source. This suggests an interesting perspective on the question of life's origin, and perhaps on the origin of consciousness.
Addy Pross received his Ph.D. in chemistry from the University of Sydney. He is currently Professor Emeritus of Chemistry at Ben-Gurion University. He has held visiting positions in the University of Lund, Stanford University, Rutgers University, University of California at Irvine, University of Padova, the Australian National University Canberra, and the University of Sydney. He is the author of What Is Life? How Chemistry Becomes Biology.