Evolution and evolvability  ·  Article

Cell-level competency and evolutionary efficiency

Cell-level competency is the ability of cells to carry out their part of development reliably, even when conditions are imperfect. In simulation, Shreesha and Levin (2023) and Hartl, Risi and Levin (2024) varied this ability and measured how an evolutionary algorithm responded. Their work asks whether competent parts change the speed and success of evolutionary search.57

Earliest held
2012, McGregor S, Vasas V, Husbands…
Most discussed in
Evolutionary Implications of Self-Assembling…, 2024
In the library
107 passages in 17 works
Rewritten
2026-10-28
01

Evolutionary algorithms as tools

Evolutionary algorithms served as search tools in these works. Lobo and Levin (2015) evolved a population of candidate regulatory networks in parallel until one matched the experimental results with zero error.1 Kriegman, Cheney and Bongard (2018) compared a control called Evo, which kept a fixed morphology and control policy over a robot's lifetime, with a variant that included development.2 They reported an incremental path that selection could climb, as legs grew and controllers were refined together.3 Kriegman and colleagues (2020) fed patterns from deployed organisms back into the algorithm as constraints.4

02

Competency in embryos

In the work of Shreesha and Levin (2023), each competent embryo was assigned a competency level. This integer set how many bubble-sort swaps the embryo could perform within its developmental cycle.5 They then placed competent embryos among hardwired ones and varied the starting proportion. At 2.5% of the population, competent embryos failed to dominate even at the highest level tested. At 10%, a level of 75 sufficed. At 20% the required level fell to 40, and at 30% a level of 10 was enough.6 Where competent embryos dominated, they did so in two or at most three generations.6

03

Noise and search efficiency

Hartl, Risi and Levin (2024) used neural cellular automata. They scaled competency continuously, from a direct encoding of the target pattern with no competency to a multi-scale competency architecture.7 Their result depended on noise. With little or no noise, the search was most efficient at low competency, and direct encoding looked preferable.8 With more noise, higher competency gave much greater efficiency. At noise levels of 0.375 and 0.5, the algorithm found no solution for direct encoding within 2000 generations.8

04

Extension to aging

Pio-Lopez, Hartl and Levin (2025) developed an evolutionary framework with multi-scale competency to study aging. They stated that, as far as they knew, aging literature so far lacked computational models that considered cellular information processing and multi-scale competency.9 Their aim was an evolutionary model that included multi-scale competency in tissue.

SourcesEach quotation was checked word for word against the passage it opens.
  1. We employed an evolutionary algorithm [114] approach to search for regulatory networks, where a population of candidate networks evolve in parallel until a network with zero error is found.Lobo D, Levin M, 2015 · Inferring regulatory networks from experimental morphological phenotypes: a… · open at passage 51
  2. The control treatment, Evo, lacks development and therefore maintains a fixed morphology and control policy in a robot as it behaves over its lifetime.Kriegman S, Cheney N, Bongard J, 2018 · How morphological development can guide evolution · open at passage 16
  3. There is then an incremental path of increasing locomotion speed that natural selection can climb by gradually growing legs to reduce the surface area touching the floorKriegman S, Cheney N, Bongard J, 2018 · How morphological development can guide evolution · open at passage 26
  4. Common patterns among the successful systems are distilled down into constraints and supplied back to the evolutionary algorithmKriegman S, Blackiston D, Levin M, Bongard J, 2020 · A scalable pipeline for designing reconfigurable organisms · open at passage 10
  5. This integer determines how many successive bubble-sort swaps will take place during its developmental cycle.Shreesha L, Levin M, 2023 · Cellular Competency during Development Alters Evolutionary Dynamics in an… · open at passage 17
  6. At 10%, embryos with a competency level of 75 could dominate; at 20%, the competency level required for domination decreased to 40; and at 30%, competent embryos dominated with a competency as low as 10Shreesha L, Levin M, 2023 · Cellular Competency during Development Alters Evolutionary Dynamics in an… · open at passage 24
  7. This allows us to continuously scale the NCA competency level from a direct encoding scheme of the target pattern (no competency) to a multi-scale competency architectureHartl B, Risi S, Levin M, 2024 · Evolutionary Implications of Self-Assembling Cybernetic Materials with… · open at passage 72
  8. for noise levels of ξc=0.375 and 0.5, the EA does not even find solutions for the direct encoding case with PD=0 in 2000 generationsHartl B, Risi S, Levin M, 2024 · Evolutionary Implications of Self-Assembling Cybernetic Materials with… · open at passage 49
  9. so far lacks computational models of aging considering cellular information processingPio-Lopez L, Hartl B, Levin M, 2025 · Aging as a Loss of Goal-Directedness: An Evolutionary Simulation and Analysis… · open at passage 94
Linked ideas
Evolvabilityrelated to
Competency is proposed to change how readily evolutionary search finds good designs, which bears on how evolvability is measured.
Hartl and colleagues used neural cellular automata as the model system in which competency level was varied.
Kriegman and colleagues likewise found that development can guide what selection can climb.
The noise results concern how cells keep a target pattern reliable when decisions are imperfect.
Basal cognitionrelated to
Competent cells making their own decisions during development are the kind of agent this idea concerns.
Both concern how an organism's own responses to conditions affect which variants selection can act on.
A covers evolutionary algorithms searching designs (metamaterials, organisms, robots); B's passage (Hartl) uses an evolutionary algorithm over neural cellular automata to test how cell competency affects search. B is studied via A's methods.
Where it is discussedPassages matching competency level, multi-scale competency, evolutionary efficiency, evolutionary algorithm
2024Evolutionary Implications of Self-Assembling Cybernetic Materials with… · Hartl B, Risi S, Levin M47
2025Aging as a Loss of Goal-Directedness: An Evolutionary Simulation and Analysis… · Pio-Lopez L, Hartl B, Levin M11
2023Cellular Competency during Development Alters Evolutionary Dynamics in an… · Shreesha L, Levin M9
2020A scalable pipeline for designing reconfigurable organisms · Kriegman S, Blackiston D, Levin M…6
2018How morphological development can guide evolution · Kriegman S, Cheney N, Bongard J5
2015Inferring regulatory networks from experimental morphological phenotypes: a… · Lobo D, Levin M4
2022Competency in Navigating Arbitrary Spaces as an Invariant for Analyzing… · Fields C, Levin M4
2025AI-driven automated discovery tools reveal diverse behavioral competencies of… · Etcheverry M, Moulin-Frier C, Oudeyer…4
2023Darwin's agential materials: evolutionary implications of multiscale competency… · Levin M3
2022Technological Approach to Mind Everywhere: An Experimentally-Grounded Framework… · Levin M3