Morphostasis and robustness of morphogenesis to noise
One model has cells compare a remembered target signal with the current one and stop growing when the two match.3 Later simulations test how noise and evolution shape this ability. Hartl and colleagues found that lineages which efficiently solved morphogenesis typically also evolved to solve morphostasis efficiently.8 Pio-Lopez and colleagues (2025) suggest that development and morphostasis still diverge.9
- Earliest held
- 2012, Lobo D, Beane WS, Levin M
- Most discussed in
- Evolutionary Implications of Self-Assembling…, 2024
- In the library
- 38 passages in 15 works
- Rewritten
- 2026-10-27
Noise and its meanings
The word noise is used in more than one sense. Pai and colleagues (2012) used developmental noise for fluctuating asymmetry, simple left-right differences that arise from noise. They separated this from biased left-right patterning, which is coordinated with the other body axes.1 A different use comes from imaging. Dolenšek and colleagues (2015) reported that membrane potential recorded from a few cells or a small stretch of plasmalemma is exceedingly noisy in time.2 That is noise in the measurement, not in the embryo.
Target memory and reinforcement
Bessonov and colleagues (2015) proposed a regeneration model based on cell memory. Each cell stores the total signal it receives. When the signal changes, the cell makes a growth-stimulating substance in proportion to the difference from the stored value.3 Growth therefore ends when the old signal is restored. The authors presented this as one answer to an open question about morphostasis. Newman (2019) took a more guarded view of bioelectricity. He wrote that it has thus far not been demonstrated to be a primary form-generating or patterning mechanism, but that voltage gradients reinforce patterns and restore them if perturbed.4 He also named canalizing evolution as a stabilizer against mutation and developmental noise.5
Simulated noise and competency
Pio-Lopez and colleagues (2022) simulated cells that infer their identities. When some cells held too high an expectation about identity, differentiation was incomplete, and the authors attributed the resulting disorder of inference to developmental noise.6 Reducing signal concentration and sensitivity in two over-precise cells cured the defect in the simulation and removed the noise.7 Hartl, Risi and Levin (2024) evolved cellular automata at several noise levels. Lineages that solved morphogenesis efficiently typically also solved morphostasis efficiently.8
Maintenance after development
Pio-Lopez, Hartl and Levin (2025) argued that existing models neglected the lack of anatomical morphostasis after development. In their simulations, aging effects appeared in long runs even when the model parameters were not perturbed. They concluded that development and morphostasis still diverge, although the tasks are close.9 They suggested that providing the tissue with a regenerative goal could reverse this decline. Their evidence comes from simulation only.
a distinct phenomenon from fluctuating asymmetry, which involves simple differences between the left and right sides derived from developmental noise
Pai VP, Vandenberg LN, Blackiston D, Levin M, 2012 · Neurally Derived Tissues in Xenopus laevis Embryos Exhibit a Consistent… · open at passage 3The MP signal from area covering few cells or a small part of plasmalemma (square, Figure 6A,B) is exceedingly noisy in the time domain
Dolenšek J, Špelič D, Klemen MS, Žalik B, Gosak M, Rupnik…, 2015 · Membrane Potential and Calcium Dynamics in Beta Cells from Mouse Pancreas… · open at passage 30If the total signal changes and becomes u, the cell produces some substance with the rate proportional to u* − u. This substance stimulates the proliferation of new cells.
Bessonov N, Levin M, Morozova N, Reinberg N, Tosenberger A…, 2015 · On a model of pattern regeneration based on cell memory · open at passage 54bioelectric establishment of voltage gradients across tissues serves to reinforce developmental patterns and restore them if perturbed during embryogenesis or wounding
Newman SA, 2019 · Inherency of Form and Function in Animal Development and Evolution · open at passage 71canalizing evolution that serves to stabilize the phenotype of an evolutionary lineage against mutation and developmental noise once it has become ecologically established
Newman SA, 2019 · Inherency of Form and Function in Animal Development and Evolution · open at passage 71There is an important developmental noise, which leads to a disorder of inference for the other cells in terms of differentiation.
Pio-Lopez L, Kuchling F, Tung A, Pezzulo G, Levin M, 2022 · Active inference, morphogenesis, and computational psychiatry · open at passage 87After the simulated biomedical intervention, as we can observe in Figure 8, the developmental defect is cured and all cells reach their location with the appropriate differentiation.
Pio-Lopez L, Kuchling F, Tung A, Pezzulo G, Levin M, 2022 · Active inference, morphogenesis, and computational psychiatry · open at passage 91lineages that efficiently evolved to solve morphogenesis in our experiments also (typically) evolve to solve morphostasis efficiently
Hartl B, Risi S, Levin M, 2024 · Evolutionary Implications of Self-Assembling Cybernetic Materials with… · open at passage 57These results suggest that development and morphostasis, while close in terms of morphological trajectories and tasks, still significantly diverge.
Pio-Lopez L, Hartl B, Levin M, 2025 · Aging as a Loss of Goal-Directedness: An Evolutionary Simulation and Analysis… · open at passage 98