VI. Earth Life Emergence: Development of Body, Brain, Selves and Societies

7. Dynamic Ecosystems

Vandermeer, John, et al. The Community Ecology of Herbivore Regulation in an Agroecosystem: Lessons from Complex Systems. BioScience. 69/12, 2019. With 30 authors from 4 continents, this article well represents the 21st century discovery that flora and fauna environs are indeed graced and structured by a domain of nonlinear mathematic phenomena, just as everywhere else. In regard, an application of theoretical aspects, as the Abstract notes, onto invasive pest and pathogen management for coffee growers results in advanced, beneficial results.

Whether an ecological community is controlled from above or below remains a popular framework and takes on especially important meaning in agroecosystems. We describe the regulation from above of three coffee herbivores, a leaf herbivore, a seed predator, and a plant pathogen by various natural enemies, emphasizing the remarkable complexity involved. We emphasize the intersection of classical ecology with the burgeoning field of complex systems with reference to chaos, critical transitions, hysteresis, basin or boundary collision, and spatial self-organization, all aimed at the applied question of pest control in the coffee agroecosystem. (Abstract excerpt)

Regulation of this herbivore is therefore effected through a complex system involving a Turing process, nonlinear indirect interactions, critical transitions, hysteresis, chaos, basin or boundary collisions, and a hypergraph, all elements of the burgeoning field of complex systems. (984)

Vergnon, Remi, et al. Repeated Parallel Evolution Reveals Limiting Similarity in Subterranean Diving Beetles. American Naturalist. 182/1, 2013. Ecologists Vergnon, Egbert van Nes, and Marten Scheffer, Wageningen University, Netherlands, with Remko Leijs, Flinders University, Australia, study this invertebrate creature as a micro exemplar of how life’s dynamic course reveals evidence of a persistence convergence. Of further interest, as the Abstract notes, is that this group, as many others today, accept and attribute to a prior “evolutionary self-organization.” See also “Self-Organized Similarity, the Evolutionary Emergence of Groups of Similar Species” by Scheffer and van Nes in Proceedings of the National Academy of Sciences (103/6230, 2006).

The theory of limiting similarity predicts that co-occurring species must be sufficiently different to coexist. Although this idea is a staple of community ecology, convincing empirical evidence has been scarce. Here we examine 34 subterranean beetle communities in arid inland Australia that share the same habitat type but have evolved in complete isolation over the past 5 million years. Although these communities come from a range of phylogenetic origins, we find that they have almost invariably evolved to share a sim8ilar size structure. The relative positions of coexisting species on the body size axis were significantly more regular across communities than would be expected by chance, with a size ratio, on average, of 1.6 between coexisting species. By contrast, species’ absolute body sizes varied substantially from one community to the next. This suggests that self-organized spacing according to limiting-similarity theory, as opposed to evolution toward preexisting fixed niches, shaped the communities. Using a model starting from random sets of founder species, we demonstrate that the patterns are indeed consistent with evolutionary self-organization. (Abstract)

Ecologists have long been puzzled by the fact that there are so many similar species in nature. Here we show that self-organized clusters of look-a-likes may emerge spontaneously from coevolution of competitors. The explanation is that there are two alternative ways to survive together: being sufficiently different or being sufficiently similar. Using a model based on classical competition theory, we demonstrate a tendency for evolutionary emergence of regularly spaced lumps of similar species along a niche axis. Indeed, such lumpy patterns are commonly observed in size distributions of organisms ranging from algae, zooplankton, and beetles to birds and mammals, and could not be well explained by earlier theory. Our results suggest that these patterns may represent self-constructed niches emerging from competitive interactions. (2006 PNAS Abstract)

Vivaldo, Gianna, et al. Network of Plants: How to Measure Similarity in Vegetable Species. arXiv:1602.05887. IMT School for Advanced Studies, Lucca and University of Firenze researchers including Guido Caldarelli cleverly show how nonlinear dynamic network theories equally applies to, and is exemplified by all manner of flora plant families. This quality is evident, for one instance, in the botanical “diaspore” process of seed dispersals. In our worldwise 21st century, nature’s rife “entanglements” at last become amenable to mathematical explanation and resolve so as to reveal and affirm this universal testament.

Despite the common misconception of nearly static organisms, plants do interact continuously with the environment and with each other. It is fair to assume that during their evolution they developed particular features to overcome problems and to exploit possibilities from environment. In this paper we introduce various quantitative measures based on recent advancements in complex network theory that allow to measure the effective similarities of various species. By using this approach on the similarity in fruit-typology ecological traits we obtain a clear plant classification in a way similar to traditional taxonomic classification. This result is not trivial, since a similar analysis done on the basis of diaspore morphological properties do not provide any clear parameter to classify plants species. Complex network theory can then be used in order to determine which feature amongst many can be used to distinguish scope and possibly evolution of plants. (Abstract)

Ward, Ashley, et al. Quorum Decision-Making Facilitates Information Transfer in Fish Schools. Proceedings of the National Academy of Sciences. 105/6948, 2008. An international team of theoretical ecologists including Ian Couzin, David Sumpter and Jens Krause report that the ‘quorum-sensing’ activity found to cohere bacterial communities (‘Wisdom of the crowds’ and ‘swarm intelligence’ is also cited.) is likewise present in groups of organisms. By such lights, a further complex adaptive feature is identified that occurs and repeats at every instance and scale.

This study shows that effective and accurate information transfer in groups may be gained only through nonlinear responses of group members to each other, thus highlighting the importance of quorum decision-making. (6948)

West, Geoffrey and James Brown. Life’s Universal Scaling Laws. Physics Today. September, 2004. A review of the theory that common properties of biological networks can explain the organization and dynamics of living systems.

Among the many fundamental variables that obey such scaling laws….are metabolic rate, life span, growth rate, heart rate, lengths of aortas and genomes, tree height, mass of cerebral grey matter, density of mitochondria, and concentration of RNA. (36) The starting point was to recognize that highly complex, self-sustaining, reproducing, living structures require close integration of enormous numbers of localized microscopic units that need to be serviced in an approximately “democratic” and efficient fashion. (38) Thus, growth and life-history events are, in general, universal phenomena governed primarily be basic cellular properties and quarter-power scaling. (40)

Wimberley, Edward. Nested Ecology: The Place of Humans in the Ecological Hierarchy. Baltimore: Johns Hopkins University Press, 2009. Pierre Teilhard de Chardin, for example, presciently saw an evolutionary advance of geological, biological, and cognitive spheres, versus the branching, twiggy bush that Darwinism claims. A Florida Gulf Coast University ecologist can now affirm the many appreciations of a deeply and truly nested nature appearing everywhere. Not a military or corporate “hierarchy,” more as Russian dolls or Chinese boxes, we find across natural ecosystems and societies open living, sentient systems that are sustained within each other. This emergent scale is traced in chapters from a Cosmic Ecology to Environmental, Social communities, and to Personal psychologies. Along the way a history of ecological theories and schools leads to novel recognitions of complementary wholes within wholes from microbes to civilizations. Wimberley contrasts this view with a “standard scientific cosmology” whose excessive reduction loses any such design, and favorably with “Christianity as a Religious Eco-cosmology” as due to St. Francis of Assisi and Teilhard, along with John Haught’s writings. From this salutary preamble is proposed a “Nested Ecological Householding” of benefit to the whole earth “…a supraorganism – a biospheric living entity” of which its human phase is part and participant.

Wu, Jianguo and Danielle Marceau. Modeling Complex Ecological Systems. Ecological Modelling. 153/1-2, 2002. An introduction to a double issue devoted to self-organizing, emergent ecosystems.

Yamazaki, Atsuko and Daniel Kamykowski. Modeling Plankton Behavior as a Complex Adaptive System. Seuront, Laurent and Peter Strutton. Handbook of Scaling Methods in Aquatic Ecology. Boca Rotan, FL: CRC Press, 2004. A further example of the ubiquitous apply of dynamical self-organization throughout the natural kingdom.

Complexity is the collective behavior of many basic but interacting units, and their interactions lead to coherent collective phenomena, which can be described only at levels higher than those of the individual units, but should emerge from the interaction among them. (544)

Young, I. M. and J. W. Crawford. Interactions and Self-Organization in the Soil-Microbe Complex. Science. 304/1634, 2004. An article for a special issue Soils – The Final Frontier, reports on many advances over the last decade which achieve a comprehensive image of earth’s fertile mantle as a dynamic, self-similar ecosystem.

In this picture, the functionality and dynamical behavior of soil emerges as a consequence of the interaction between the physical and biological processes as mediated by the structure of soil. The soil-microbe complex can be viewed as a self-organizing system capable of adapting to prevailing conditions. (1636)

Zaoli, Silvia, et al. Covariations in Ecological Scaling Laws Fostered by Community Dynamics. Proceedings of the National Academy of Sciences. 114/10672, 2017. As this section commenced in 2004, an agreed presence and discernment of endemic environmental patterns and processes was much in abeyance. Here École Polytechnique Fédérale de Lausanne, and University di Padova (Amos Maritan) theorists contribute to a later 2010s affirmation that they indeed are much in place, and what kind of forms do they take. A commentary in the same issue Integrating Macroecology through a Statistical Mechanics of Adaptive Matter by Pablo Marquet notes the achievement.

Empirical laws portraying patterns in ecology are routinely observed in marine and terrestrial environments. Such patterns are recurrent but also show features that are distinctive of each ecosystem. For example, the number of species in an ecosystem increases with its area according to a well-defined mathematical law, but the rate of increase may vary across different ecosystem types. We show that different ecological patterns are linked to each other in a way that if one is changed, the others are affected as well. We verify our predictions on available empirical datasets and unravel yet unknown features of natural ecosystems, suggesting directions for empirical research. (Significance)

Zelnik, Yuval, et al. High-Integrity Human Intervention in Ecosystems: Tracking Self-Organization Modes. PLoS Computational Biology. September, 2021. Into the 2020s, Swedish University of Agricultural Sciences, Hebrew University of Jerusalem and Ben-Gurion University ecological theorists including Ehud Meron contend that a full appreciation and application of nature’s dynamic spontaneities complexities (the river bank is finally untangled and explained) can well inform and guide future mitigations (droughts, fires) and improvements (biodiversity, etc.)

Humans play major roles in shaping and transforming the ecology of Earth. Unlike natural drivers of ecosystem change, human interventions may involve planning and management, but often with detrimental results. Using model studies and aerial-image analysis, we argue that a successful management calls for an understanding of the dynamic self-organization modes that drive ecosystem change. We demonstrate this approach with two examples: grazing control in drought-prone ecosystems, and the rehabilitation of degraded vegetation by water harvesting. We show that spatially non-uniform grazing can aid a resilience to droughts, and that fragmental restoration along contour bands is better than vegetation stripes. (Abstract excerpt)

Zhang, WenJun, et al. Neural Network Modeling of Ecosystems. Ecological Modelling. 201/3-4, 2007. Another well-studied exemplar of complex, self-organizing systems, neural net geometries and interactions are of much service to explicate ultra-intricate, nested dynamic biotas, in this instance cabbage patch growth in China.

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