Speciation is the process by which one or more species arises from a common ancestor, and “macroevolution” refers to patterns and processes at and above the species level – or, transitions in higher taxa, such as new families, phyla or genera. “Macroevolution” is contrasted with “microevolution,” evolutionary change within populations, due to migration, assortative mating, selection, mutation and drift. In the evolutionary synthesis of the 1930’s and 40’s, Haldane (1932), Dobzhansky (1937), Mayr (1942), and Simpson (1944) argued that (...) the origin of species and higher taxa were, given the right environmental conditions and sufficient time, the product of the same microevolutionary factors yielding change within populations. Dobzhansky reviewed the evidence from genetics, and argued, “nothing in the known macroevolutionary phenomena would require other than the known genetic principles for causal explanation” (Dobzhansky, 1951, 17). In sum, genetic variation between species was not different in kind from the genetic variation within species. Dobzhansky concluded that one may “reluctantly put an equal sign” between micro- and macroevolution. In this chapter, I review arguments for and against this "neo-Darwinian" consensus on speciation, as well as debates concerning macroevolution and punctuated equilibrium. (shrink)
The comparison between biological and social macroevolution is a very important (though insufficiently studied) subject whose analysis renders new significant possibilities to comprehend the processes, trends, mechanisms, and peculiarities of each of the two types of macroevolution. Of course, there are a few rather important (and very understandable) differences between them; however, it appears possible to identify a number of fundamental similarities. One may single out at least three fundamental sets of factors determining those similarities. First of all, (...) those similarities stem from the fact that in both cases we are dealing with very complex non-equilibrium (but rather stable) systems whose principles of functioning and evolution are described by the General Systems' Theory, as well as by a number of cybernetic principles and laws. -/- Secondly, in both cases we do not deal with isolated systems; in both cases we deal with a complex interaction between systems of organic systems and external environment, whereas the reaction of systems to external challenges can be described in terms of certain general principles (that, however, express themselves rather differently within the biological reality, on the one hand, and within the social reality, on the other). -/- Thirdly, it is necessary to mention a direct ‘genetic’ link between the two types of macroevolution and their mutual influence. -/- It is important to emphasize that the very similarity of the principles and regularities of the two types of macroevolution does not imply their identity. Rather significant similarities are frequently accompanied by enormous differences. For example, genomes of the chimpanzees and the humans are very similar – with differences constituting just a few per cent; however, there are enormous differences with respect to intellectual and social differences of the chimpanzees and the humans hidden behind the apparently ‘insignificant’ difference between the two genomes. Thus, in certain respects it appears reasonable to consider the biological and social macroevolution as a single macroevolutionary process. This implies the necessity to comprehend the general laws and regularities that describe this process, though their manifestations may display significant variations depending on properties of a concrete evolving entity (biological, or social one). An important notion that may contribute to the improvement of the operationalization level as regards the comparison between the two types of macroevolution is the one that we suggested some time ago – the social aromorphosis (that was developed as a counterpart to the notion of biological aromorphosis well established within Russian evolutionary biology). We regard social aromorphosis as a rare qualitative macrochange that increases in a very significant way complexity, adaptability, and mutual influence of the social systems, that opens new possibilities for social macrodevelopment. In our paper we discuss a number of regularities that describe biological and social macroevolution and that employ the notions of social and biological aromorphosis such as ones of the module evolution (or the evolutionary ‘block assemblage’), ‘payment for arogenic progress’ etc. (shrink)
When philosophers of physics explore the nature of chance, they usually look to quantum mechanics. When philosophers of biology explore the nature of chance, they usually look to microevolutionary phenomena, such as mutation or random drift. What has been largely overlooked is the role of chance in macroevolution. The stochastic models of paleobiology employ conceptions of chance that are similar to those at the microevolutionary level, yet different from the conceptions of chance often associated with quantum mechanics and Laplacean (...) determinism. (shrink)
There are very significant conceptual links between theories of social macroevolution and theories of the World System development. It is shown that the growth of the World System complexity and integrity can be traced through a system of phase transitions of macroevolution. The first set of phase transition is connected with the agrarian, industrial, and information-scientific revolutions (that are interpreted as changes of “production principles”). The second set consists of phase transitions within one production principle. These phase transitions (...) are analyzed on the basis of the World System urbanization dynamics, but they can be traced with respect to the other (cultural, economic, technological, demographic, political, etc.) dimensions of the World System development. (shrink)
Darwin’s main contribution to modern biology was to make clear that all history of life on earth is dominated by a simple principle, which is usually summarised as 'descent with modification'. However, interpretations about how this modification is produced have been controversial. In light of the data provided by recent studies on molecular biology, developmental biology, genomics, and other biological disciplines we discuss, in this paper, how Darwin's theory may apply to two main 'types' of evolution: that occurring in the (...) prebiotic world and that regarding the acquisition of major key-innovations differentiating higher-taxa, which makes up part of the so-called macroevolution. We argue that these studies show that evolution is a fascinating, complex and multifaceted process, with different mechanisms drivin it on different occasions and in different places. (shrink)
The theory of punctuated equilibrium has been proposed as a challenge to the modern synthesis of evolutionary theory. Two important issues are raised. The first is scientific: whether morphological change as observed in the paleontological record is essentially always associated with speciation events. This paper argues that there is at present no empirical support for this claim: the alleged evidence is based on a definitional fallacy. The second issue is epistemological: whether macroevolution is an autonomous field of study, independent (...) from microevolutionary knowledge. It is herein argued that macroevolution and microevolution are not decoupled in two senses: identity at the level of events and compatibility of theories. But macroevolution is autonomous in the epistemologically important sense: macroevolutionary theories are not reducible to microevolutionary principles. It is finally pointed out that the discipline of macroevolution is notoriously lacking in theoretical constructs of great import and generality. (shrink)
There are very significant conceptual links between theories of social macroevolution and theories of the World System development. It is shown that the growth of the World System complexity and integrity can be traced through a system of phase transitions of macroevolution. The first set of phase transition is connected with the agrarian, industrial, and information-scientific revolutions (that are interpreted as changes of “production principles”). The second set consists of phase transitions within one production principle. These phase transitions (...) are analyzed on the basis of the World System urbanization dynamics, but they can be traced with respect to the other (cultural, economic, technological, demographic, political, etc.) dimensions of the World System development. (shrink)
Stephen Jay Gould argued that replaying the “tape of life” would result in a radically different evolutionary outcome. Some biologists and philosophers, however, have pointed to convergent evolution as evidence for robust replicability in macroevolution. These authors interpret homoplasy, or the independent origination of similar biological forms, as evidence for the power of natural selection to guide form toward certain morphological attractors, notwithstanding the diversionary tendencies of drift and the constraints of phylogenetic inertia. In this paper, I consider the (...) implications of homoplasy for the debate over the nature of macroevolution. I argue that once the concepts of contingency and convergence are fleshed out, it becomes clear that many instances of homoplasy fail to negate Gould’s overarching thesis, and may in fact support a Gouldian view of life. My argument rests on the distinction between parallelism and convergence, which I defend against a recent challenge from developmental biology. I conclude that despite the difficulties in defining and identifying parallelism, the concept remains useful and relevant to the contingency controversy insofar as it underscores the common developmental origins of iterated evolution. (shrink)
The idea of genetic assimilation, that environmentally induced phenotypes may become genetically fixed and no longer require the original environmental stimulus, has had varied success through time in evolutionary biology research. Proposed by Waddington in the 1940s, it became an area of active empirical research mostly thanks to the efforts of its inventor and his collaborators. It was then attacked as of minor importance during the ‘‘hardening’’ of the neo-Darwinian synthesis and was relegated to a secondary role for decades. Recently, (...) several papers have appeared, mostly independently of each other, to explore the likelihood of genetic assimilation as a biological phenomenon and its potential importance to our understanding of evolution. In this article we briefly trace the history of the concept and then discuss theoretical models that have newly employed genetic assimilation in a variety of contexts. We propose a typical scenario of evolution of genetic assimilation via an intermediate stage of phenotypic plasticity and present potential examples of the same. We also discuss a conceptual map of current and future lines of research aimed at exploring the actual relevance of genetic assimilation for evolutionary biology. (shrink)
Given the numerous parallels between the archaeological and paleontological records, it is not surprising to find a considerable fit between macroevolutionary approaches and methods used in biology – for example, cladistics and clade-diversity measures – and some of those that have long been used in archaeology – for example, seriation. Key, however, is recognizing that this methodological congruence is illusory in terms of how evolution has traditionally been viewed in biology and archaeology. (Published Online November 9 2006).
The review focuses on Huxley’s debt to Richard Goldschmidt and Cyril Darlington. I discuss the conceptions of the genome developed by Goldschmidt and Darlington and their continuing relevance.
Systems Biology and the Modern Synthesis are recent versions of two classical biological paradigms that are known as structuralism and functionalism, or internalism and externalism. According to functionalism (or externalism), living matter is a fundamentally passive entity that owes its organization to external forces (functions that shape organs) or to an external organizing agent (natural selection). Structuralism (or internalism), is the view that living matter is an intrinsically active entity that is capable of organizing itself from within, with purely internal (...) processes that are based on mathematical principles and physical laws. At the molecular level, the basic mechanism of the Modern Synthesis is molecular copying, the process that leads in the short run to heredity and in the long run to natural selection. The basic mechanism of Systems Biology, instead, is self-assembly, the process by which many supramolecular structures are formed by the spontaneous aggregation of their components. In addition to molecular copying and self-assembly, however, molecular biology has uncovered also a third great mechanism at the heart of life. The existence of the genetic code and of many other organic codes in Nature tells us that molecular coding is a biological reality and we need therefore a framework that accounts for it. This framework is Code biology, the study of the codes of life, a new field of research that brings to light an entirely new dimension of the living world and gives us a completely new understanding of the origin and the evolution of life. (shrink)
The ontological dependence of one domain on another is compatible with the explanatory autonomy of the less basic domain. That autonomy results from the fact that the relationship between two domains can be very complex. In this paper I distinguish two different types of complexity, two ways the relationship between domains can fail to be transparent, both of which are relevant to evolutionary biology. Sometimes high level explanations preserve a certain type of causal or counterfactual information which would be lost (...) at the lower level; I argue that this is central to the proper understanding of the adaptationist program. Sometimes high level kinds are multiply realised by lower level kinds: I argue that this is central to the understanding of macroevolution. (shrink)
Hierarchical expansions of the theory of natural selection exist in two distinct bodies of thought in evolutionary biology, the group selection and the species selection traditions. Both traditions share the point of view that the principles of natural selection apply at levels of biological organization above the level of the individual organism. This leads them both to considermultilevel selection situations, where selection is occurring simultaneously at more than one level. Impeding unification of the theoretical approaches of the multilevel selection traditions (...) are the different goals of investigators in the different subdisciplines and the different types of data potentially available for analysis. We identify two alternative approaches to multilevel situations, which we termmultilevel selection [1] andmultilevel selection [2]. Of interest in the former case are the effects of group membership onindividual fitnesses, and in the latter the tendencies for the groups themselves to go extinct or to found new groups (i.e., group fitnesses). We argue that: neither represents the entire multilevel selection process; both are aspects of any multilevel selection situation; and both are legitimate approaches, suitable for answering different questions. Using this formalism, we show that: multilevel selection [2] does not require emergent group properties in order to provide an explanatory mechanism of evolutionary change; multilevel selection [1] is usually more appropriate for neontological group selection studies; and species selection is most fruitfully considered from the point of view of multilevel selection [2]. Finally we argue that the effect hypothesis of macroevolution, requiring, in selection among species, both the absence of group effects on organismic fitness (multilevel selection [1]), and the direct determination of species fitnesses by those of organisms, is untestable with paleontological data. Furthermore, the conditions for the effect hypothesis to hold are extremely restrictive and unlikely to apply to the vast majority of situations encountered in nature. (shrink)
Evolutionary theory (ET) is teeming with probabilities. Probabilities exist at all levels: the level of mutation, the level of microevolution, and the level of macroevolution. This uncontroversial claim raises a number of contentious issues. For example, is the evolutionary process (as opposed to the theory) indeterministic, or is it deterministic? Philosophers of biology have taken different sides on this issue. Millstein (1997) has argued that we are not currently able answer this question, and that even scientific realists ought to (...) remain agnostic concerning the determinism or indeterminism of evolutionary processes. If this argument is correct, it suggests that, whatever we take probabilities in ET to be, they must be consistent with either determinism or indeterminism. This raises some interesting philosophical questions: How should we understand the probabilities used in ET? In other words, what is meant by saying that a certain evolutionary change is more or less probable? Which interpretation of probability is the most appropriate for ET? I argue that the probabilities used in ET are objective in a realist sense, if not in an indeterministic sense. Furthermore, there are a number of interpretations of probability that are objective and would be consistent with ET under determinism or indeterminism. However, I argue that evolutionary probabilities are best understood as propensities of population-level kinds. (shrink)
Modern biology is ambivalent about the notion of evolutionary progress. Although most evolutionists imply in their writings that they still understand large-scale macroevolution as a somewhat progressive process, the use of the term “progress” is increasingly criticized and avoided. The paper shows that this ambivalence has a long history and results mainly from three problems: (1) The term “progress” carries historical, theoretical and social implications which are not congruent with modern knowledge of the course of evolution; (2) An incongruence (...) exists between the notion of progress and Darwin’s theory of selection; (3) It is still not possible to give more than a rudimentary definition of the general patterns that were generated during the macroevolution of organisms. The paper consists of two parts: the first is a historical overview of the roots of the term “progress” in evolutionary biology, the second discusses epistemological, ontological and empirical problems. It is stated that the term has so far served as a metaphor for general patterns generated amongst organisms during evolution. It is proposed that a reformulation is needed to eliminate historically imported implications and that it is necessary to develop a concept for an appropriate empirical description of macroevolutionary patterns. This is the third way between, on the one hand, using the term indiscriminately and, on the other hand, ignoring the general patterns that evolution has produced. (shrink)
In 1937, just as Dobzhansky published the book that later generations would laud as the foundation of the modern synthesis, the American Naturnlist published a symposium on "supraspecific variation in nature and in classification." Alfred C. Kinsey, who later became one of America's most controversial intellectuals for his study of basic behaviors in another sort of WASP,1 led off the symposium with a summary of his extensive work on a family of gall wasps, the Cynipidae. In his article, Kinsey strongly (...) advocated the central theme of the developing synthesis: Evolution at all scales, particularly macroevolution, could be explained by the genetic mechanisms observed in laboratories and local populations. He first complained that some geneticists and naturalists were still impeding a synthesis with their insistence upon causal separation of levels: "Just as some of the geneticists have insisted that the laboratory genetics may explain the nature and origin of Mendelian races, but not of natural species, so others indicate that the qualities of higher categories must be explained on bases other than those involved in species" (1937, p. 208). He then defended the central postulate. (shrink)
A number of authors have pointed to “convergent evolution” as evidence for the central role of natural selection in shaping predictable trajectories of macroevolution. However, there are numerous conceptual and empirical difficulties that arise in broadly appealing to the frequency of homoplasy as evidence for a non-contingently constrained adaptational design space. Most important is the need to distinguish between convergent (externally constrained) and parallel (internally constrained) evolution, and to consider how the respective frequencies of these significantly different sources of (...) homoplasy affect a strong adaptationist view of life. In this paper, I critically evaluate Simon Conway Morris’s use of the homoplasy literature to support his argument for a non-contingent, counterfactually stable account of macroevolutionary pattern. In so doing, I offer a conception of parallelism which avoids the charge that it differs from convergence merely in degree and not in kind. I argue that although organisms sharing a homoplastic trait will also share varying degrees of homology, it is the underlying developmental homology with respect to the generators directly causally responsible for the homoplastic event that defines parallel evolution and non-arbitrarily distinguishes it from convergence. The notion of “screening-off” is used to distinguish the proximal generators of a homoplastic trait from its more distal genetic causes (such as a master control gene). (shrink)
This paper develops a critical response to John Beatty’s recent (2006) engagement with Stephen Jay Gould’s claim that evolutionary history is contingent. Beatty identifies two senses of contingency in Gould’s work: an unpredictability sense and a causal dependence sense. He denies that Gould associates contingency with stochastic phenomena, such as drift. In reply to Beatty, this paper develops two main claims. The first is an interpretive claim: Gould really thinks of contingency has having to do with stochastic effects at the (...) level of macroevolution, and in particular with unbiased species sorting. This notion of contingency as macro-level stochasticity incorporates both the causal dependence and the unpredictability senses of contingency. The second claim is more substantive: Recent attempts by other scientists to put Gould’s claim to the test fail to engage with the hypothesis that species sorting sometimes resembles a lottery. Gould’s claim that random sorting is a significant macroevolutionary phenomenon remains an intriguing and largely untested live hypothesis about evolution. (shrink)
The allegedly alternative theories of Phyletic Gradualism and Punctuated Equilibria are examined as regards the nature of their differences. The explanatory value of both models is determined by establishing their actual connection with reality. It is concluded that they are to be considered complementary rather than mutually exclusive at all levels of infraspecific, specific, and supraspecific evolution. So, in order to be described comprehensively, the pathways of evolution require at least two distinct models, each based on a discrete range of (...) real phenomena. [Phyletic Gradualism; Punctuated Equilibria; evolutionary theories; divergence models; additive speciation; microevolution; macroevolution; anagenesis.]. (shrink)
We have demonstrated, using the Cantor dust method, that the statistical distribution of appearance and disappearance of rodents species (Arvicolid rodent radiation in Europe) follows power laws strengthening the evidence for a fractal structure set. Self-similar laws have been used as model for the description of a huge number of biological systems. With Nottale we have shown that log-periodic behaviors of acceleration or deceleration can be applied to branching macroevolution, to the time sequences of major evolutionary leaps (global life (...) tree, sauropod and theropod dinosaurs postural structures, North American fossil equids, rodents, primates and echinoderms clades and human ontogeny). The Scale-Relativity Theory has others biological applications from linear with fractal behavior to non-linear and from classical mechanics to quantum mechanics. (shrink)
The distribution of organisms in morphologic space is clumpy. Cats are like felids, dogs are like canids and snails are (mostly) like gastropods. But cats are not like dogs and snails are not like clams. This clumpy distribution of morphology has long posed one of the greatest challenges to evolutionary biologists. Does it represent the extinction and disappearance of a oncecontinuous distribution of morphologies, clades perched on the summits of persistent selective peaks ala Sewell Wright, or a primary signature of (...) the evolutionary processes? And if the latter, what processes are responsible for generating it? Although often couched in discussions of the origin of higher taxa, such taxa are but proxies for this clumpy distribution, and ultimately the latter is the critical issue for macroevolution and for Stephen Jay Gould’s opus. Underneath all the controversies over whether species constitute individuals, whether speciation serves to divide intra-specific adaptation driven by natural selection from a set of inter- and supra-specific evolutionary processes, and over the impact of catastrophic mass extinctions on evolutionary trends, the fundamental issue is simply one of clumpiness (or, if you prefer, the inhomogeneous distribution of morphologies). Iurii Filipchenko, a Russian geneticist and the mentor of Theodosius Dobzhansky, introduced the term macroevolution in 1927 because he believed that the origin of the characters associated with higher taxa (those beyond the species level) required a different process of evolution. Filipchenko believed macroevolution was driven by cytoplasmic inheritance, but his general argument was consistent with other saltationists and macro-mutationists of the time, including the paleontologist Henry Fairfield Osborne and the geneticist Richard Goldschmidt. These evolutionary biologists shared the.. (shrink)
Weak links, in the form of inadequacies in both reasoning and supporting evidence, exist at several critical steps in the derivation of an hierarchical concept of evolution from punctuated equilibria. Punctuation itself is predicated on a distorted reading of phyletic change as phyletic gradualism, and of allopatric speciation as the instantaneous formation of unchanging typological taxa. The concept of punctuation is further confounded by the indescriminate employment of the same term to denote both a causal explanation for evolutionary change and (...) an outcome of substantiated evolutionary processes. Even when the intended usage for the term is specified, each denotation of punctuation entails respective drawbacks. As a causal explanation, punctuation clearly belongs to the class of quantum theories with all their attendant impedimenta, including special salsatory non-adaptive mechanisms of evolutionary change. Redefinition of punctuation as a pattern of morphologic change reduces it to one possible outcome of known microevolutioanry processes, thus obviating any need for an hierarchical explanation of macroevolution. While vacillation between usages has preserved the term in the literature, the end result of this obfuscation has been a circle of faulty reasoning in which the pattern of punctuation is invoked as its own proof. Widespread confusion concerning what constitutes an adequate test of punctuation is directly attributable to imprecision in both the original and revised formulations of the concept.The argument for species-level selection is based on the typological and philosphically flawed premise of species as individuals, and further requires the hypothesis of heritable emergent properties, for which empirical evidence is lacking. (shrink)
Striedter's accessible concept-based book is strong on the macroevolution of brains and the developmental principles that underlie how brains evolve on that scale. In the absence of greater attention to microevolution, natural selection, and sexual selection, however, it is incomplete and not fully modern on the evolution side. Greater biological integration is needed.
It is commonly accepted by those who consider macroevolution as a process decoupled from microevolution that its apparent jerkiness (and, hence, incompatibility with principles of population genetics) results from the structural complexity of epigenetic systems, since all complex cybernetic systems are expected to behave discontinuously. To analyse the validity of this assumption, the process of self-improvement has been analysed in a complex cybernetic system by means of computer simulations. It turns out that the investigated system tends to develop by (...) accumulation of as small structural changes as possible, while larger changes are likely to result in the collapse of the system rather than in its persistence or improvement. This implies that cybernetic considerations alone cannot justify the claim that the very nature of epigenetic systems induces evolution by discrete steps rather than by gradual accumulation of small changes. (shrink)
The architects of punctuated equilibrium and species selection as well as more recent workers (Vrba) have narrowed the original formulation of species selection and made it dependent upon so-called emergent characters. One criticism of this narrow version is the dearth of emergent characters with a consequent diminution in the robustness of species selection as an important evolutionary process. We argue that monomorphic species characters may at times be the focus of selection and that under these circumstances selection at the organism (...) level is by-passed due to the absence of critical variance. Selection therefore shifts to the species level where variability reemerges in a clade. The absence of critical variance among organisms prevents effect macroevolution from operating. If species-wide properties are important in macroevolutionary processes, as we contend, systematists should pay more attention to their elucidation. (shrink)
The recent discovery of a phenomenon of craniofacial growth, called craniofacial contraction, throws a new light on the process of hominization. The main interest of this discovery lies in a growth principle combining the different craniofacial units, that is to say, the neurocranium (neural skull), the chondrocranium (basal skull) and the splanchnocranium (visceral archs including the mandible). Until recent years, these different parts were considered as neighbouring element without any morphogenic or morphodynamic connection. But now, we know that the (...) morphogenesis of the base of the skull governs that of the face. This basicranial morphogenesis is the occipital flexion. It generates morphogenic correlations with the face since embryogenesis. The ontogenic pathway of this phenomenon is the craniofacial contraction. It concerns embryonic dynamics connected with the spatial development of the embryonic neural system, the neural tube. These morphodynamics are common to each primate species, but they are differenciated by the amplitude of the embryonic contraction. We ask ourself the question: is hominization of the neurocephalic embryogenesis, that is the craniofacial contraction, plausible over a very long period, with gradual and chaotic evolutionary pathways, or, on the contrary, is the complexity of such an embryonic phenomenon, a limiting factor generating determined and predictible ontogenic thresholds? The study of extant and fossil primate skulls demonstrates that species are organized around 6 levels of embryonic contraction, which, starting from 60 millions years, evolve from the less to the most contracted skull. Among each ontogenic level, living and fossil species develop from the same embryonic system but between both levels, the embryos suddenly are reorganized. Therefore, I have defined an evolutive ontogenic unity, that is the fundamental ontogenesia. The cephalic pole has a fundamental ontogenesis, meaning that, beyond the diversities, we can see the same contraction in many living and extinct species. The ontogenic diversities are the result of the microevolution and are not predictible. In such a perspective, the ontogenic morphodynamics evolve with chaotic trajectories. But, between two embryonic levels, or two fundamental ontogeneses, evolutionary modalities are different. Eventually, from 60 millions years to XXth century, we observe the same phenomenon than during human ontogenesis; hominization of the cephalic pole is a craniofacial contraction. The evolutive pathway is stable, whatever the number of thresholds, the cranial shape changes but the ontogenic trajectory is preserved. This is a macroevolution because the embryonic system is reorganized. The logics of the phenomenon are an increasing dynamization, the human ontogenesis is the more unstable and the longer morphodynamics to stabilize the craniofacial contraction. To conclude, hominization is an iteration of an ontogenic process when embryos reach successive dynamic thresholds. The attractors are neither static, periodic, nor chaotic because the successive ontogenic trajectories are themselves in a stable evolutive trajectory, and the results with increasing contraction, complexified neocortical tissues and cephalocaudal reorganization are predictible. During hominization, irreversibility and innovations do not emerge with chaotic determinism, but with harmonic determinism in association with the correlations established between the embryonic tissues. When the system is destabilized, the embryonic systems do not forget the previous ontogenic pattern, on the contrary, they develop the pattern with new dynamical conditions. This sort of phenomenon is not described in the sciences of complexity. In the present case, we are in front of many millions years and the necessity to propose new concepts such as a new familly of attractors, namely the harmonic attractors. (shrink)
A method of phylogenetic reconstruction as proposed by a number of scientists of the Senckenberg Research Institute is discussed. The method is based on functional-morphological studies, the evolutionary adaptation principle of Bock and Von Wahlert (1965) and so-called model reconstruction. It is argued in this paper that direction of the adaptation process cannot be determined because of lack of knowledge about particular selective forces and that theories of model reconstruction are not open to contradiction in the sense of Popperian falsification. (...) Although it has been claimed that the method provides the only valid directional argument for morphoclines in cladistic studies, it remains unclear how to proceed when morphoclines show contradictory polarities. Moreover, it is doubtful whether polarities of morphoclines can be determined independently of phylogenetic hypotheses, and also whether the use of multistate morphoclines is methodologically valid. By relying on a particular evolutionary theory, i.e. the neo-Darwinian theory, and consequently assigning natural selection as the major agent of directional progress, the Senckenburg method of phylogenetic reconstruction restricts itself to microevolutionary change and, therefore, cannot be used when other hypotheses on the evolutionary process appear to explain the speciation process more plausibly, i.e. hypotheses on macroevolution. Furthermore, it is an unproved statement that evolution always proceeds according to the principle of economy. (shrink)
This paper locates the contributions of Kauffman and Ayala to this symposium in the context of recent discussions of the adequacy of the Modern Synthesis. The neglect of morphology and development described by Kauffman is understandable in view of the belief that selection is the most powerful evolutionary force. His idea that properties of order may be explained by nonselective mechanisms is also examined. The paper subsequently takes up Ayala's criticism of S.J. Gould's view that macroevolution is a process (...) "decoupled" from microevolution. It is argued that the idea of species selection makes Gould's antireductionism ontological in character; this contrasts with Ayala's contention that the decoupling is merely epistemological. (shrink)
