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

6. Dynamic Fractal Network Ecosystems

Siteur, Koen, et al. Phase-separation physics underlies new theory for the resilience of patchy ecosystems. PNAS. 120/2, 2023. A century and six decades later, in our global phase, Dutch and Chinese ecotheorists at last reach the deep roots of “tangled banks” by an integrations with condensed matter phenomena as it actively proceeds through transitional emergences. The second quote goes on to record the consequence of critical states.

Spatial self-organization of ecosystems into large-scales enables diverse organisms to cope with variable environmental conditions and to buffer degradation. Scale-dependent feedbacks have provided a framework for self-organized formations such as arid areas or mussel beds. Here, we cite an alternative approach by way of the complications of a biotic or abiotic basis such as herbivores, sediment, or nutrients. Building on physical theory for phase-separation dynamics, we show that patchy phases are more vulnerable at small spatial scales. By this view, the initiation of coarse aggregations can offer a new indicator to signal tipping points and radical habitat loss.

Our study contributes a better perspective based on self-organized patchiness to understand irregular ecosystems that lack feedbacks associated with spatial Turing patterns and disturbances due to scale-free modes that typify self-organized criticality.

Solari, Aldo, et al. On Skipjack Tuna Dynamics: Similarity at Several Scales. Seuront, Laurent and Peter Strutton, eds. Handbook of Scaling Methods in Aquatic Ecology. Boca Rotan, FL: CRC Press, 2004. Of special interest is the finding that these tuna populations have invariant structures because their nautical environment itself is an iteration of temperature patterns, surface waves, wind effects, and so on, which carry on into the depths of a “fractal ocean.”

Sole, Ricard. Scaling Laws in the Drier. Nature. 449/151, 2007. A synopsis of two technical reports in the same issue as breakthrough examples of how complex system theories can reveal the presence of dynamic, scale-free, self-organization due to localized interactions, in this case for the spatial distribution of vegetation. Based on the Kalahari and Iberian ecosystems studied, this work is said to be of especial import because changes in such patterns can be employed to portend a shift to an arid desert condition, so measures might be taken to avert it.

Sole, Ricard and Jordi Bascompte. Self-Organization in Complex Ecosystems. Princeton: Princeton University Press, 2006. Sole lists the Universitat Pompeu Fabra in Barcelona and Santa Fe Institute, while Bascompte cites the Spanish Research Council and University of California, Santa Barbara. In this collaboration, the field of a dynamic ecological science is brought to a new phase of experimental and theoretical synthesis. Living nature is perceived not in an equilibrium balance but as distinguished by far-from-equilibrium nested networks from microbial realms to species macroevolution. Importantly, the authors go on to attribute such “complex adaptive systems” everywhere to an universal, independent source.

This book presents theoretical evidence of the potential of nonlinear ecological interactions to generate nonrandom, self-organized patterns at all levels. (1) Life itself is a good example: (irreducible) nucleic acids, proteins, or lipids are not “alive” by themselves. It is the cooperation among different sets that actually creates a self-sustained, evolvable pattern called life. Over the last decades of the twentieth century the shortcomings of the reductionist approach had become increasingly apparent, and at some point a new type of integrative biology began to emerge. (11) Such universality reminds us of a different perspective of evolutionary change emphasizing the role of fundamental constraints. These theories suggest that basic, universal laws of organization shape the large-scale architecture of biological systems. (14)

A striking, widespread feature of many complex systems is that some of their properties are reproduced at different scales in such a way that we perceive the same patterns when looking at different subparts of the same system. (127) Actually, empirical evidence has been mounting in support of the unexpected possibility that many different systems arising in disparate disciplines such as physics, biology, and economy may share some intriguingly similar scale invariant features. (127)

Stauffer, Dietrich, et al. Evolutionary Ecology in Silico: Evolving Food Webs, Migrating Population and Speciation. Physica A. 352/202, 2005. An update and review of Stauffer and colleagues on-going project to understand dynamic ecosystems in terms of complex systems science.

Biology is a storehouse of exotic and fascinating phenomena at all levels of organization – from sub-cellular level to cells, tissues, organs, organisms, colonies,…, up to level of ecosystems. In this paper we review some of the exciting new developments in modeling dynamical phenomena at the level of ecosystems using some concepts and techniques that have been found extremely useful in studying self-organized complex adaptive systems. (203)

Storch, David, et al. Scaling Biodiversity. Cambridge, UK: Cambridge University Press, 2007. With co-editors James Brown and Pablo Marquet, about a major project based in the Southwest environs of the Santa Fe Institute to discern endemic features of the distribution, occupancy, rarity, and hierarchical topology of metazoan species. Not yet seen in full, to be reviewed further, an important contribution on how such a nested fractality can help appreciate and conserve precious animal richness.

Sugihara, George and Hao Ye. Cooperative Network Dynamics. Nature. 458/979, 2009. A review of Ugo Bastolla, et al in the same issue on nested ecosystem mutualisms which serve to minimize competition and foster diversity. The same phenomena are then found to benefit vendor-customer relations.

Thus, whereas competition normally limits the number of species that can co exist (as tough competitive markets often tend towards monopoly), the nested cooperative models studied here reduce competition and allow the system to support more species, or higher biodiversity. (979) Nestedness is not an isolated property of plant–animal communities, however, but appears in various social contexts, including the organization of the New York garment industry4 and as disassortativity in the topology of the Fedwire network. Indeed, it is possible that the appearance of similar topology among diverse cooperative networks may be a result of simple shared assembly rules. (979)

Suweis, Samir, et al. Emergence of Structural and Dynamical Properties of Ecological Mutualistic Networks. Nature. 500/449, 2013. We post this paper by Samir Suweis and Amor Maritan, University of Padova, with Filippo Simini, Northeastern University, and Jayanth Banavar, University of Maryland, as an example among many of how the presence of such equally real interconnections between all the pieces and components from biochemicals to neurons and creatures. In regard, this shift and advance is engendering a much expanded understanding of proactive living systems. Of further notice, as this paper exhibits, is the finding that the same dynamic topologies universally characterize and repeat at every strata and instance from genomes to brains and species. See also “Networks: Exapnding Evolutionary Thinking” by Eric Bapteste, et al in Trends in Genetics (29/8, 2013) which evokes this quiet revolution.

Mutualistic networks are formed when the interactions between two classes of species are mutually beneficial. They are important examples of cooperation shaped by evolution. Mutualism between animals and plants plays a key role in the organization of ecological communities. Such networks in ecology have generically evolved a nested architecture independent of species composition and latitude. Here we show that nested interaction networks could emerge as a consequence of an optimization principle aimed at maximizing the species abundance in mutualistic communities. Using analytical and numerical approaches, we show that because of the mutualistic interactions, an increase in abundance of a given species results in a corresponding increase in the total number of individuals in the community, as also the nestedness of the interaction matrix. Our work provides a unifying framework for studying the emergent structural and dynamical properties of ecological mutualistic networks. (Abstract excerpts)

Tarnita, Corina, et al. A Theoretical Foundation for Multi-Scale Regular Vegetation Patterns. Nature. 541/398, 2017. Princeton University, University of Strathclyde, Hebrew University of Jerusalem, and University of Idaho systems botanists describe a sophisticated, multi-media confirmation of intrinsic self-organized patterns and dynamics. The many studies that this Ecosystem section has reported on since the early 2000s do indeed seem to be untangling and confirming nature’s universal scale. See also Spatial Self-Organization of Ecosystems by Robert Pringle and Corina Tarnita in the Annual Review of Entomology (62/359, 2017).

Self-organized regular vegetation patterns are widespread and thought to mediate ecosystem functions such as productivity and robustness, but the mechanisms underlying their origin and maintenance remain disputed. Two competing hypotheses are currently debated. On the one hand, models of scale-dependent feedbacks, whereby plants facilitate neighbours while competing with distant individuals, can reproduce various regular patterns identified in satellite imagery. Owing to deep theoretical roots and apparent generality, scale-dependent feedbacks are widely viewed as a unifying and near-universal principle of regular-pattern formation despite scant empirical evidence. On the other hand, many overdispersed vegetation patterns worldwide have been attributed to subterranean ecosystem engineers such as termites, ants, and rodents.

Here we provide a general theoretical foundation for self-organization of social-insect colonies, validated using data from four continents, which demonstrates that intraspecific competition between territorial animals can generate the large-scale hexagonal regularity of these patterns. Using Namib Desert fairy circles as a case study, we present field data showing that these landscapes exhibit multi-scale patterning. These patterns and other emergent properties, such as enhanced resistance to and recovery from drought, instead arise from dynamic interactions in our theoretical framework, which couples both mechanisms. The potentially global extent of animal-induced regularity in vegetation—which can modulate other patterning processes in functionally important ways—emphasizes the need to integrate multiple mechanisms of ecological self-organization. (Abstract)

Thompson, John. Mutualistic Webs of Species. Science. 312/372, 2006. A review of a research article by Jordi Bascompte, et al in the same issue on the self-organization of asymmetric coevolutionary networks in nested nature.

Complex mutualistic webs are therefore not haphazard collections of specialists and generalists. Evolution and coevolution appear to shape these multispecific interactions in a predictable manner regardless of the exact composition of species or ecosystem,… (372)

Touboul, Jonathan, et al. On The Complex Dynamics of Savanna Landscapes. Proceedings of the National Academy of Sciences. Online January 29, 2018. Brandeis, Yale (Ann Staver), and Princeton University (Simon Levin) researchers offer further quantifications of intrinsic ordering principles which underlie and sustain nature’s seemingly tangled flora and fauna.

This paper makes a significant contribution both to ecological theory and to an understanding more generally regarding how complex dynamics can emerge in mathematical models from quite simple underlying assumptions. Empirical and theoretical work has suggested that savanna–forest systems exhibit bistability, potentially flipping from one state to another in the face of environmental change. Here, we show that the dynamics of those systems may be much more complicated and present surprising responses to environmental variability. From a mathematical point of view, the models that we explore exhibit a rich array of behaviors and responses to random perturbations, and we suggest that such dynamics may arise in a variety of contexts.

Tu, Chengyi, et al. Reconciling Cooperation, Biodiversity and Stability in Complex Ecological Communities. Nature Scientific Reports. 9/5580, 2019. With an opening nod to Alfred Lotka and Vito Volterra from the early 1900s, Chengyi Tu, UC Berkeley, Samir Suweis, Marco Formentin, and Amos Maritan, University of Padova, and Jacopo Grilli, International Centre for Theoretical Physics, Trieste (search names) continue to finesse mathematical theories which are well exemplified by active creaturely groupings. It is again averred that cooperative relations are most important for achieving viable success.

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