Browsing by Author "McShea, DW"

Now showing 1 - 9 of 9

Open Access
An externalist teleology
(Synthese) Babcock, G; McShea, DW
Open Access
Applying the Prigogine view of dissipative systems to the major transitions in evolution
(Paleobiology, 2022-11-13) De Castro, C; McShea, DW
Ilya Prigogine's trinomial concept is, he argued, applicable to many complex dissipative systems, from physics to biology and even to social systems. For Prigogine, this trinomial - functions, structure, fluctuations - was intended to capture the feedback-rich relations between upper and lower levels in these systems. The main novelty of his vision was his view of causation, in which the causal arrow runs downward from dissipative structures to their components or functions. Following this insight, some physicists and biophysicists are beginning to apply terms formerly used mainly in biology, such as evolution, adaptation, learning, and life-like behavior, to physical and chemical nonequilibrium systems. Here, instead, we apply Prigogine's view to biology, in particular to evolution, and especially the major transitions in evolution (MTE), arguing that at least the hierarchical transitions - the transitions in individuality - follow a trajectory anticipated by the trinomial. In this trajectory, formerly free-living organisms are transformed into functions within a larger organic structure. The Prigogine view also predicts that, consistent with available data, the increase in number of hierarchical levels in organisms should accelerate over time. Finally, it predicts that, on geological timescales, ecosystems and Gaia in particular will tend to de-Darwinize or machinify their component organisms.
Open Access
Complexity by Subtraction
(Evolutionary Biology, 2013) McShea, DW; Hordijk, W
The eye and brain: standard thinking is that these devices are both complex and functional. They are complex in the sense of having many different types of parts, and functional in the sense of having capacities that promote survival and reproduction. Standard thinking says that the evolution of complex functionality proceeds by the addition of new parts, and that this build-up of complexity is driven by selection, by the functional advantages of complex design. The standard thinking could be right, even in general. But alternatives have not been much discussed or investigated, and the possibility remains open that other routes may not only exist but may be the norm. Our purpose here is to introduce a new route to functional complexity, a route in which complexity starts high, rising perhaps on account of the spontaneous tendency for parts to differentiate. Then, driven by selection for effective and efficient function, complexity decreases over time. Eventually, the result is a system that is highly functional and retains considerable residual complexity, enough to impress us. We try to raise this alternative route to the level of plausibility as a general mechanism in evolution by describing two cases, one from a computational model and one from the history of life. © 2013 Springer Science+Business Media New York.
Open Access
Drosophila mutants suggest a strong drive toward complexity in evolution
(Evolution and Development, 2012) Fleming, L; McShea, DW
The view that complexity increases in evolution is uncontroversial, yet little is known about the possible causes of such a trend. One hypothesis, the Zero Force Evolutionary Law (ZFEL), predicts a strong drive toward complexity, although such a tendency can be overwhelmed by selection and constraints. In the absence of strong opposition, heritable variation accumulates and complexity increases. In order to investigate this claim, we evaluate the gross morphological complexity of laboratory mutants in Drosophila melanogaster, which represent organisms that arise in a context where selective forces are greatly reduced. Complexity was measured with respect to part types, shape, and color over two independent focal levels. Compared to the wild type, we find that D. melanogaster mutants are significantly more complex. When the parts of mutants are categorized by degree of constraint, we find that weakly constrained parts are significantly more complex than more constrained parts. These results support the ZFEL hypothesis. They also represent a first step in establishing the domain of application of the ZFEL and show one way in which a larger empirical investigation of the principle might proceed.
Open Access
Four solutions for four puzzles
(Biology and Philosophy, 2012-09-01) Brandon, RN; McShea, DW
Barrett et al. (Biol Philos, 2012) present four puzzles for the ZFEL-view of evolution that we present in our 2010 book, Biology's First Law: The Tendency for Diversity and Complexity to Increase in Evolutionary Systems. Our intent in writing this book was to present a radically different way to think about evolution. To the extent that it really is radical, it will be easy to misunderstand. We think Barrett et al. have misunderstood several crucial points and so we welcome the opportunity to clarify. © 2012 Springer Science+Business Media B.V.
Open Access
Resolving teleology’s false dilemma
(Biological Journal of the Linnean Society, 2022) Babcock, G; McShea, DW
Abstract This paper argues that the account of teleology previously proposed by the authors is consistent with the physical determinism that is implicit across many of the sciences. We suggest that much of the current aversion to teleological thinking found in the sciences is rooted in debates that can be traced back to ancient natural science, which pitted mechanistic and deterministic theories against teleological ones. These debates saw a deterministic world as one where freedom and agency is impossible. And, because teleological entities seem to be free to either reach their ends or not, it was assumed that they could not be deterministic. Mayr’s modern account of teleonomy adheres to this basic assumption. Yet, the seeming tension between teleology and determinism is illusory because freedom and agency do not, in fact, conflict with a deterministic world. To show this, we present a taxonomy of different types of freedom that we see as inherent in teleological systems. Then we show that our taxonomy of freedom, which is crucial to understanding teleology, shares many of the features of a philosophical position regarding free will that is known in the contemporary literature as ‘compatibilism’. This position maintains that an agent is free when the sources of its actions are internal, when the agent itself is the deterministic cause of those actions. Our view shows that freedom is not only indispensable to teleology, but also that, contrary to common intuitions, there is no conflict between teleology and causal determinism.
Open Access
Synergies Among Behaviors Drive the Discovery of Productive Interactions
(Biological Theory, 2023-03-01) Keenan, JP; McShea, DW
When behaviors assemble into combinations, then synergies have a central role in the discovery of productive patterns of behavior. In our view—what we call the Synergy Emergence Principle (SEP)—synergies are dynamic attractors, drawing interactions toward greater returns as they happen, in the moment. This Principle offers an alternative to the two conventionally acknowledged routes to discovery: directed problem solving, involving forethought and planning; and the complete randomness of trial and error. Natural selection has a role in the process, in humans favoring the maintenance and improvement of certain key underlying capabilities, such as prosocial helping and episodic foresight, but selection is not required for discovery by synergy (which occurs too rapidly for selection anyway). Here we discuss the consequences of the SEP for the evolution in humans of key synergies such as tool usage and interactions that reward cooperation, show how discovery by synergy and the selection of synergy-supporting abilities formed a positive feedback loop, and show how synergies can combine, forming clusters and packages that are the core of institutions and cultures. Finally, clusters and packages represent an intermediate level of organization above the individual and below whole society, with consequences for our understanding of the major transitions in evolution.
Open Access
Three Trends in the History of Life: An Evolutionary Syndrome
(Evolutionary Biology, 2016-12-01) McShea, DW
The history of life seems to be characterized by three large-scale trends in complexity: (1) the rise in complexity in the sense of hierarchy, in other words, an increase in the number of levels of organization within organisms; (2) the increase in complexity in the sense of differentiation, that is, a rise in the number of different part types at the level just below the whole; and (3) a downward trend, the loss of differentiation at the lowest levels in organisms, a kind of complexity drain within the parts. Here, I describe the three trends, outlining the evidence for each and arguing that they are connected with each other, that together they constitute an evolutionary syndrome, one that has recurred a number times over the history of life. Finally, in the last section, I offer an argument connecting the third trend to the reduction at lower levels of organization in “autonomy”, or from a different perspective, to an increase in what might be called the “machinification” of the lower levels.
Open Access
Upper-directed systems: A new approach to teleology in biology
(Biology and Philosophy, 2012-09-01) McShea, DW
How shall we understand apparently teleological systems? What explains their persistence (returning to past trajectories following errors) and their plasticity (finding the same trajectory from different starting points)? Here I argue that all seemingly goal-directed systems-e. g., a food-seeking organism, human-made devices like thermostats and torpedoes, biological development, human goal seeking, and the evolutionary process itself-share a common organization. Specifically, they consist of an entity that moves within a larger containing structure, one that directs its behavior in a general way without precisely determining it. If so, then teleology lies within the domain of the theory of compositional hierarchies. © 2012 Springer Science+Business Media B.V.