Paleontological Patterns, Macroecological Dynamics and the Evolutionary Process

Here we consider evolutionary patterns writ large in the fossil record. We argue that Darwin recognized but downgraded or de-emphasized several of these important patterns, and we consider what a renewed emphasis on these patterns can tell us about the evolutionary process. In particular, one of the key patterns we focus on is the role geographic isolation plays in fomenting evolutionary divergence; another one of the key patterns is stasis of species; the final pattern is turnovers, which exist at several hierarchical scales, including regional ecosystem replacement and pulses of speciation and extinction. We consider how each one of these patterns are related to the dynamic of changing ecological and environmental conditions over time and also investigate their significance in light of other concepts including punctuated equilibria and hierarchy theory. Ultimately, we tie each of these patterns into a framework involving macroecological dynamics and the important role environmental change plays in shaping evolution from the micro- to macroscale.     

Adaptive Radiations in the Context of Macroevolutionary Theory: A Paleontological Perspective

Adaptive radiations are often invoked anytime clades show significant bursts of diversification, but it is important to not simply assume that any radiating clade constitutes an adaptive radiation. In addition, several highly relevant macroevolutionary concepts including the Turnover Pulse Hypothesis, the Effect Hypothesis, exaptation, and species selection, have not been considered in the adaptive radiations literature. Here, these concepts are integrated into the theory of evolutionary radiations in general, and adaptive radiations in particular, and different types of evolutionary radiations are identified, including geographic radiations. Special emphasis is placed on considering the role that abiotic as opposed to biotic factors may play in motivating diversification during evolutionary radiations. Further, recent paleontological data suggesting that rather than organismal adaptation it may be principally abiotic factors, such as climate change and a taxon??s presence in a geographically complex region, that cause clades to diversify will be described. The fossil record, the source of the initial hallmark examples of adaptive radiation, now appears to show little concrete support for this phenomenon.     

Evolutionary Theory and the Social uses of Biology

Stephen Jay Gould is rightly remembered for many different kinds of contributions to our intellectual life. I focus on his criticisms of uses of evolutionary ideas to defend inegalitarian doctrines and on his attempts to expand the framework of Darwinian evolutionary theory. I argue that his important successes in the former sphere are applications of the idea of local critique, grounded in careful attention to the details of the inegalitarian proposals. As he became more concerned with the second project, Gould was inclined to suggest that the abuses of evolutionary ideas rested on an insufficiently expanded Darwinism. I suggest that what is valuable in Gould's contribution to general evolutionary theory is the original claim about punctuated equilibrium (advanced, with Niles Eldredge in1972), and the careful defense of that claim through the accumulation of paleontological evidence. I try to show that the more ambitious program of a hierarchical expansion of neo-Darwinism is misguided, and that the endeavor to go beyond local critique fails.     

Ninety years of the Paleontological Society

The establishment in 1916 and the subsequent 90-year history of the Russian (later All-Union and All-Russia) Paleontological Society are discussed. The society’s works and endeavors over ninety years were closely connected with the needs of practical geology, and primarily with paleontological research, the development of a stratigraphic basis, and their use in paleogeography, paleoecology, and biosphere studies.     

Network Theory and the Formation of Groups Without Evolutionary Forces

This paper presents a modified random network model to illustrate how groups can form in the absence of evolutionary forces, assuming groups are collections of entities at any level of organization. This model is inspired by the Zero Force Evolutionary Law, which states that there is always a tendency for diversity and complexity to increase in any evolutionary system containing variation and heredity. That is, in the absence of evolutionary forces, the expectation is a continual increase in diversity and complexity at any level of biological hierarchy. I show that, when modeled, this expectation of increasing variation results not only in the formation of groups, but also in a higher probability of group formation than is found in a model that is purely random.     

How to Rethink Evolutionary Theory: A Plurality of Evolutionary Patterns

Nature has recently depicted the empirical advancements of the theory of evolution as a confrontation between “reformists”, that claim for an urgent rethinking of the standard neo-Darwinian approach including so far neglected factors and processes, and “conservatives” who reply “all is well” about the current evolutionary research programme based on genetic variation and natural selection. The fight is mainly around genetic reductionism, but it seems inconclusive. Reformists stress very important factors, but they are still missing a coherent proposal about the architecture of the future extended evolutionary theory. Conservative react defensively, relying just on non-essential add-ons to the old and stable neo-Darwinian core. We analyze the debate and we propose an interpretation. Evolutionary biology is a rapidly expanding field. The bone of contention is how to update and extend the central core of the Darwinian legacy. We propose here the idea that what is happening in the field today is a development of the evolutionary research programme, whose structure is composed of a set of compatible and integrated evolutionary patterns. Evolutionary biology has been extended over its history by the inclusion of more and more patterns, rather than by revision to core theory. Niles Eldredge’s “Hierarchy Theory” is an example of global structure (meta-theory) aiming at incorporating and unifying the currently observed evolutionary patterns.     

Multiple Explanations in Darwinian Evolutionary Theory

Variational evolutionary theory as advocated by Darwin is not a single theory, but a bundle of related but independent theories, namely: (a) variational evolution; (b) gradualism rather than large leaps; (c) processes of phyletic evolution and of speciation; (d) causes for the formation of varying individuals in populations and for the action of selective agents; and (e) all organisms evolved from a common ancestor. The first four are nomological-deductive explanations and the fifth is historical-narrative. Therefore evolutionary theory must be divided into nomological and historical theories which are both testable against objective empirical observations. To be scientific, historical evolutionary theories must be based on well corroborated nomological theories, both evolutionary and functional. Nomological and general historical evolutionary theories are well tested and must be considered as strongly corroborated scientific theories. Opponents of evolutionary theory are concerned only with historical evolutionary theories, having little interest in nomological theory. Yet given a well corroborated nomological evolutionary theory, historical evolutionary theories follow automatically. If understood correctly, both forms of evolutionary theories stand on their own as corroborated scientific theories and should not be labeled as facts.     

Paleontological Evidence to Date the Tree of Life

Michael J. Benton and