V. Life's Corporeal Evolution Develops, Encodes and Organizes Itself: An Earthtwinian Genesis Synthesis

6. Dynamic Fractal Network Ecosystems

Fortuna, Miguel, et al. Evolving Digital Ecological Networks. PLoS Computational Biology. 9/3, 2013. Systems theorists Fortuna, Princeton University, with Luis Zaman, Aaron Wagner and Charles Ofria, Michigan State University, open another window onto the added dimension of intrinsic self-organizing phenomena and forces that serve to channel life’s developmental emergence. These endogenous, independent principles then are seen in effect at each and every scale and creaturely instance.

Evolving digital ecological networks are webs of interacting, self-replicating, and evolving computer programs (i.e., digital organisms) that experience the same major ecological interactions as biological organisms (e.g., competition, predation, parasitism, and mutualism). Despite being computational, these programs evolve quickly in an open-ended way, and starting from only one or two ancestral organisms, the formation of ecological networks can be observed in real-time by tracking interactions between the constantly evolving organism phenotypes. (Abstract)

Franklin, Oskar, et al. Organizing Principles for Vegetation Dynamics. Nature Plants. 6/5, 2020. We cite this entry by a 29 member international team with postings in Austria, Sweden, the UK, Australia, the USA, Japan, Finland, Switzerland, China, France, the Netherlands, Israel, Luxembourg, and South Africa including Roderick Dewar and Ehud Meron as a good example of how the 21st century project to detect and quantify common self-organized patterns and processes across natural environs is achieving its grand goal. We note that the implied, independent mathematical source from whence these features arise also needs to be realized.

Substantial progress has been made in understanding individual plant processes. But the greater challenge is to predict vegetation dynamics in a changing environment. We propose that three general organizing principles — natural selection, self-organization and entropy maximization — can facilitate the development of reliable dynamic vegetation models (DVMs). Here, we aim to clarify their theoretical basis, along with potentials and limit, for improving our understanding of vegetation dynamics and our ability to predict vegetation change. (Abstract excerpt)

Gamarra, Javier. Metapopulations in Multifractal Landscapes. Proceedings of the Royal Society B. 272/1815, 2005. By using the parameter of lacunarity – a measure of landscape texture or spatial aggregation – the pervasive presence of a fractal self-similarity can be quantified and expressed.

Garlaschelli, Diego, et al. Universal Scaling Relations in Food Webs. Nature. 423/165, 2003. From predator-prey cycles to river networks and vascular systems, a common power-law self-similarity organizes the same efficient pattern.

Gautestad, Arlid and Ivar Mysterud. Intrinsic Scaling Complexity in Animal Dispersion and Abundance. American Naturalist. 165/1, 2005. Progress toward a generalized theoretical framework for populations kinetics and spatial dynamics based on statistical mechanics and complex systems.

We describe, simulate, and discuss three testable aspects of a model for multiscaled habitat use at the individual level: (1) scale-free distribution of movement steps under influence of self-reinforcing site fidelity, (2) fractal spatial dispersion of intra-home range relocations, and (3) nonasymptotic expansion of observed intra-home range patch use with increasing set of relocations. (44)

Getzin, Stephan, et al. Discovery of Fairy Circles in Australia Supports Self-Organization Theory. Proceedings of the National Academy of Sciences. Early Edition, March, 2016. An eleven person team from Germany, Israel, and Australia including Ehud Meron quantify how these curious flora patterns are an exemplary manifestation of innate physical topologies and dynamics.

Pattern-formation theory predicts that vegetation gap patterns, such as the fairy circles of Namibia, emerge through the action of pattern-forming biomass–water feedbacks and that such patterns should be found elsewhere in water-limited systems around the world. We report here the exciting discovery of fairy-circle patterns in the remote outback of Australia. Using fieldwork, remote sensing, spatial pattern analysis, mathematical modeling, and pattern-formation theory we show that the Australian gap patterns share with their Namibian counterparts the same characteristics but are driven by a different biomass–water feedback. These observations are in line with a central universality principle of pattern-formation theory and support the applicability of this theory to wider contexts of spatial self-organization in ecology. (Significance)

Gilarranz, Luis, et al. Effects of Network Modularity on the Spread of Perturbation Impact in Experimental Metapopulations. Science. 357/199, 2017. Spanish National Research Group CSIC, McGill University, and University of Seville integrative ecologists including Jordi Bascompte argue for a common propensity for creatures to form distinctly viable community subassemblies in an environment. See also The Importance of Being Modular by Marta Sales-Pardo in the same issue.

Networks with a modular structure are expected to have a lower risk of global failure. However, this theoretical result has remained untested until now. We used an experimental microarthropod metapopulation to test the effect of modularity on the response to perturbation. We perturbed one local population and measured the spread of the impact of this perturbation, both within and between modules. Our results show the buffering capacity of modular networks. To assess the generality of our findings, we then analyzed a dynamical model of our system. We show that in the absence of perturbations, modularity is negatively correlated with metapopulation size. However, even when a small local perturbation occurs, this negative effect is offset by a buffering effect that protects the majority of the nodes from the perturbation. (Abstract)

In the 1970s, ecologists began to speculate that modular systems—which are organized into blocks or modules—can better contain perturbations and are therefore more resilient against external damage. This simple concept can be applied to any networked system, be it an ecosystem, cellular metabolism, traffic flows, human disease contagion, a power grid, or an economy. However, experimental evidence has been lacking. On page 199 of this issue, Gilarranz et al. provide empirical evidence showing that modular networked systems do indeed have an advantage over nonmodular systems when faced with external perturbations. (Sales-Pardo)

Goyal, Akshit, et al.. Closed Ecosystems Extract Energy through Self-Organized Nutrient Cycles. PNAS. 120/52, 2023.. 120/52, 2023. Into 2023, MIT, CalTech, Clark University and University of Chicago ecotheorists find still more way that nature’s intricate flora and fauna are formed and sustained as universal dynamic complex environs.

Our planet is a self-sustaining ecosystem powered by solar energy, but roughly closed to matter. Many ecosystems on Earth recycle nutrients by self-organizing stable cycles. However, existing ecological models do not express these features as observed in such global and biotic regimes. Here, we advance a hypothesis that explains their presence by a thermodynamic feedback loop that enables diverse metabolic communities to stabilize nutrient cycles. Our results highlight that self-organization promotes the efficiency and stability of complex ecosystems at extracting energy from the environment. (Abstract)

Green, David and Suzanne Sadedin. Interactions Matter – Complexity in Landscapes and Ecosystems. Ecological Complexity. 2/2, 2005. From a new journal, a survey of this “new paradigm for ecology” which finds ecosystems to exemplify nonlinear, self-organizing, critically poised, nested networks.

Green, David, et al. Complexity in Landscape Ecology. Berlin: Springer, 2006. Research ecologists provide a good primer on how natural environments are graced by and thoroughly express the principles of dynamical systems of self-organization, fractal scale-invariance, modularity, and cellular automata. A proper grasp of this endemic viability will then contribute to a global biosphere sustainability.

Greenbaum, Gili and Nina Fefferman. Application of Networks Methods for Understanding Evolutionary dynamics in Discrete Habitats. Molecular Ecology. 26/11, 2017. Ben-Gurion University of the Negev and University of Tennessee bioecologists provide another tutorial entry to an effective application of interactive network phenomena to ecosystem populations. Once again, the invitation is that these common connective aspects, although invisible, are in fact a major formative property. See also The Multilayer Nature of Ecological Networks by Shai Pilosof, et al in Nature Ecology & Evolution (1/0101, 2017), along with Complex Networks in Ecology by Gili Greenbaum, et al in Israel Journal of Ecology & Evolution (61/2, 2015).

In populations occupying discrete habitat patches, gene flow between habitat patches may form an intricate population structure. In such structures, the evolutionary dynamics resulting from interaction of gene-flow patterns with other evolutionary forces may be exceedingly complex. In the last decades, network theory – a branch of discrete mathematics concerned with complex interactions between discrete elements – has been applied to address several problems in population genetics by modelling gene flow between habitat patches using networks. Here, we present the idea and concepts of modelling complex gene flows in discrete habitats using networks. Our goal is to raise awareness to existing network theory applications in molecular ecology studies, as well as to outline the current and potential contribution of network methods to the understanding of evolutionary dynamics in discrete habitats. (Abstract)

Griffen, Blaine and John Drake. Scaling Rules for the Final Decline to Extinction. Proceedings of the Royal Society B. 276/1361, 2009. From the University of Georgia Odum School of Ecology, a report that the same geometries, as if due to an original, complementary genetic code, seem to occur at each and every phase of life and death.

The consistency of certain spatial and temporal dynamics among highly different nonlinear ecological systems is astounding. Such scaling rules have been found to characterize individual behaviour; the use of space by organisms; life-history patterns of individuals; population growth, regulation and abundance; community stability; and, by integrating across species ensembles, even patterns of biodiversity across regional landscapes. (1361)

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