Transition of unicellular to multicellular one cannot be described by random mutations.
Photo Credit: Vladimir Petrov.
Scientific Frontline: Extended "At a Glance" Summary: The Regulated Symbiosis Hypothesis of Multicellularity
The Core Concept: The regulated symbiosis hypothesis posits that the evolutionary transition from unicellular to multicellular organisms was a guided, programmed process driven by internal patterns of morphogenesis. This framework suggests that the emergence of complex life is a purposeful adaptive system where random genetic mutations and natural selection play secondary roles.
Key Distinction/Mechanism: Unlike traditional Darwinian theory, which relies on exhaustive random mutations and selection to generate complexity, this concept argues that coordinated genomic restructuring, transport system integration, and cellular adhesion require pre-programmed recognition between cells. Analogous to networking computers, cellular components must be fundamentally programmed to interact as a cohesive whole rather than arriving at compatibility through random chance.
Origin/History: The concept was proposed by Alexey Melkikh, a physicist at the Ural Federal University (UrFU), and published in the journal BioSystems in November 2026. The research leverages evolutionary timelines—noting that organisms like sea sponges appeared over 600 million years ago—to demonstrate the mathematical improbability of random mutation models.
Major Frameworks/Components:
- Regulated Symbiosis: The mechanism by which single cells combine into a unified organism through a predefined control system.
- Morphogenetic Programming: Internal, hidden patterns that dictate the necessary restructuring of genomes, immunity, and cell division regulation.
- Mathematical Improbability of Random Search: The total number of sea sponges to ever exist (estimated at 10²²) is vastly eclipsed by the number of possible genome rearrangements (approximately 4 to the power of 300 million), rendering random selection statistically impossible.
- Programmed Evolutionary Trajectory: The assertion that even the last universal common ancestor (LUCA) emerged as part of a directed, system-level evolutionary process.
Branches of Science: Evolutionary Biology, Theoretical Biology, Evolutionary Genetics, Biophysics, Systems Biology
Future Application: This paradigm shift could influence computational models of evolutionary algorithms, enhance synthetic biology efforts to engineer artificial multicellular systems, and refine approaches to understanding complex systemic diseases driven by cellular communication failures.
Why It Matters: Reconceptualizing evolution as a fundamentally programmed, non-random process challenges core tenets of the modern evolutionary synthesis, demanding new mathematical and biological frameworks to explain the rapid emergence of biological complexity on Earth.
Alexey Melkikh, a professor at the Ural Federal University Department of Physics, has proposed a concept for the origin of multicellular organisms that differs from Darwinian theory, which relies on random mutations and natural selection. According to his theory, evolution is not a random process but a guided, programmed system wherein randomness and selection play a secondary role. The paper has been published in the journal BioSystems.
"The origin of multicellular organisms from unicellular ones is an extremely complex process. The concept of regulated symbiosis is proposed as the mechanism of their formation. Such symbiosis is carried out through a control system operating on the basis of internal, hidden patterns of morphogenesis," Melkikh explains.
The transition from unicellular to multicellular organisms cannot be explained by random mutations alone, as it would require a statistically improbable number of sequential steps. Combining cells into a single organism requires the coordinated restructuring of the genome, transport systems, immunity, adhesion, and cell division regulation. Each cell must biochemically recognize its role and adjacent cells, requiring highly coordinated genetic regulatory networks across cellular boundaries.
Analogous to computer networks, the physicist notes that physical connection alone is insufficient; units must possess pre-existing programmed protocols to communicate and operate as a cohesive system. This "new" functionality must be specified in advance.
The scientist gives the example of the sea sponge, which appeared more than 600 million years ago. If one assumes one sponge per square meter of ocean, the total number of sponges that have ever lived over half a billion years would be approximately \(10^{22}\). This is fundamentally smaller than the number of possible genomic rearrangements (approximately \(4^{300,000,000}\)). A working combination cannot be found by random search.
"Even LUCA (the last universal common ancestor) did not arise as a result of exhaustive selection or random mutations, but as part of a single programmed process—the evolution of life on Earth. Evolution—and, in a broader sense, life itself—is an extremely complex, purposeful adaptive system," Melkikh concludes.
Published in journal: BioSystems
Authors: A.V. Melkikh
Source/Credit: Ural Federal University | Anastasia Pyankova
Edited by: Scientific Frontline
Reference Number: ebio111126_01
