Punctuated Equilibrium: A Model for Administrative Evolution

(Excerpt) In 1972, paleontologists Niles Eldredge and Stephen Jay Gould published a paper that challenged the conventional understanding of the nature and rate of biological evolution. Addressing the absence of support in the fossil record for the accepted model of species change, the scholars observed that significant genetic development within a single species did not appear to follow the kind of gradual path that Charles Darwin had postulated. Instead, they concluded that the great majority of species appear with geological abruptness in the fossil record and then persist in stasis until their extinction. They observed that species evolution is much more often the product of dramatic quantum shifts over relatively short periods of time, than the kind of gradualism envisioned by Darwin. Eldredge and Gould referred to the evolutionary structure produced by this phenomenon as a punctuated equilibrium —long periods of relative stasis ( equilibrium ) interrupted and re-defined ( punctuated ) by rare but dramatic instances of evolutionary change. They referred to the relatively brief (in geological terms) periods where the normal stasis in species development is interrupted by dramatic species developments as unresolvable geological moments. This theory, more fully developed in Gould\u27s later work, was controversial from its inception, but nonetheless, has revolutionized the study of biological evolution, and remains a central topic of debate to this day. In their synthesis of the public discourse concerning the punctuated equilibrium theory, editors Albert Somit and Steven Peterson argued that the model, [b]y providing a different metaphor for explaining social phenomena . . . may assist us in better understanding human behavior in all of its manifestations. Aware of similar assessments of the efficacy of his theory, Gould did not question the widespread invocation or the extensive utility of the metaphorical linkage, but confessed to being more interested in exploring ways in which the theory might supply truly causal insights about other scales and styles of change. One field outside the natural sciences where causal insights can be gleaned from the basic logic of the punctuated equilibrium theory is the study of administrative regulation. Specifically, the theory provides a compelling template for an analysis of the historical development of administrative and regulatory structures in the United States. Political scientists have already relied on the punctuated equilibrium model to explain the volatile pace of policy innovation, particularly in the environmental area, the nature of American constitutional development, and other aspects of political and governmental change. Some legal scholars have noted the apt analogies that can be drawn between Eldredge and Gould\u27s theory and analysis of the evolution of regulatory regimes in the area of securities regulation and other fields

Cultural adaptations: Is it conceptually coherent to apply natural selection to cultural evolution?

Critics of Darwinian approaches to the study of the evolution of human and social behavior often express their dissent claiming that cultural evolution is Lamarckian. By this they mean two things. First, that contrary to natural selection, in Lamarckian mechanisms of use and disuse plus the inheritance of acquired traits, the modifications in an organism arise as a solution to the environmental problem at hand, i.e., variation is not blind; and second, that the acquired trait is transmitted to the offspring by imitation or learning. In this paper I will reconstruct informally the theory of natural selection as it was used by Darwin in order to show that the fact that cultural evolution has these Lamarckian features does not imply that it cannot evolve by natural selection. The appeal to Darwin´s original writings has two advantages. On the one hand, the way he applies the theory makes it more transparent than in contemporary applications which are its fundamental concepts and structure. On the other, Darwin holds that Lamarckian mechanisms can be causally responsible for variations on which natural selection operates, thus showing that it is possible to hold a theory of natural selection that is not incompatible with these alleged Lamarckian features of cultural evolution.Los críticos de los enfoques que intentan estudiar la evolución conductual humana y social con enfoques darwinianos suelen describir tal rechazo con la afirmación: "La evolución cultural es lamarckiana". con esto se refieren, por un lado, al hecho de que, supuestamente a diferencia de la selección natural, en los mecanismos lamarckianos de uso y desuso más la herencia de caracteres adquiridos, la modificación en el rasgo del organismo en cuestión surge como solución al problema ambiental en juego, la variación no es ciega, y por el otro, que el rasgo adquirido se transmite a la descendencia. Así, los rasgos culturales se proponen para solucionar ciertos problemas ambientales y son transmitidos a la descendencia por imitación o aprendizaje. En este trabajo se reconstruirá informalmente la teoría de la selección natural tal como era utilizada por Darwin con el objetivo de mostrar que el hecho de que la evolución cultural tenga estas características lamarckianas no implica que no puede evolucionar por selección natural. La apelación a los escritos originales de Darwin tiene dos beneficios. Por un lado, la forma en que aplica la teoría resulta más transparente que en las aplicaciones actuales cuáles son los conceptos fundamentales de la teoría y cómo su estructura. Por el otro, Darwin sostiene que los mecanismos lamarckianos pueden ser causantes de la variación sobre la cual la selección natural funciona, mostrando que es posible sostener una teoría de la selección natural que no se incompatible con estos supuestos rasgos lamarckianos de la evolución cultural.Fil: Ginnobili, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; Argentina. Universidad Nacional de Quilmes; Argentin

Complex systems and the history of the English language

Complexity theory (Mitchell 2009, Kretzschmar 2009) is something that historical linguists not only can use but should use in order to improve the relationship between the speech we observe in historical settings and the generalizations we make from it. Complex systems, as described in physics, ecology, and many other sciences, are made up of massive numbers of components interacting with one another, and this results in self-organization and emergent order. For speech, the “components” of a complex system are all of the possible variant realizations of linguistic features as they are deployed by human agents, speakers and writers. The order that emerges in speech is simply the fact that our use of words and other linguistic features is significantly clustered in the spatial and social and textual groups in which we actually communicate. Order emerges from such systems by means of self-organization, but the order that arises from speech is not the same as what linguists study under the rubric of linguistic structure. In both texts and regional/social groups, the frequency distribution of features occurs as the same pattern: an asymptotic hyperbolic curve (or “A-curve”). Formal linguistic systems, grammars, are thus not the direct result of the complex system, and historical linguists must use complexity to mediate between the language production observed in the community and the grammars we describe. The history of the English language does not proceed as regularly as like clockwork, and an understanding of complex systems helps us to see why and how, and suggests what we can do about it. First, the scaling property of complex systems tells us that there are no representative speakers, and so our observation of any small group of speakers is unlikely to represent any group at a larger scale—and limited evidence is the necessary condition of many of our historical studies. The fact that underlying complex distributions follow the 80/20 rule, i.e. 80% of the word tokens in a data set will be instances of only 20% of the word types, while the other 80% of the word types will amount to only 20% of the tokens, gives us an effective tool for estimating the status of historical states of the language. Such a frequency-based technique is opposed to the typological “fit” technique that relies on a few texts that can be reliably located in space, and which may not account for the crosscutting effects of text type, another dimension in which the 80/20 rule applies. Besides issues of sampling, the frequency-based approach also affects how we can think about change. The A-curve immediately translates to the S-curve now used to describe linguistic change, and explains that “change” cannot reasonably be considered to be a qualitative shift. Instead, we can use to model of “punctuated equilibrium” from evolutionary biology (e.g., see Gould and Eldredge 1993), which suggests that multiple changes occur simultaneously and compete rather than the older idea of “phyletic gradualism” in evolution that corresponds to the traditional method of historical linguistics. The Great Vowel Shift, for example, is a useful overall generalization, but complex systems and punctuated equilibrium explain why we should not expect it ever to be “complete” or to appear in the same form in different places. These applications of complexity can help us to understand and interpret our existing studies better, and suggest how new studies in the history of the English language can be made more valid and reliable

Making the most of clade selection

Clade selection is unpopular with philosophers who otherwise accept multilevel selection theory. Clades cannot reproduce, and reproduction is widely thought necessary for evolution by natural selection, especially of complex adaptations. Using microbial evolutionary processes as heuristics, I argue contrariwise, that (1) clade growth (proliferation of contained species) substitutes for clade reproduction in the evolution of complex adaptation, (2) clade-level properties favoring persistence – species richness, dispersal, divergence, and possibly intraclade cooperation – are not collapsible into species-level traits, (3) such properties can be maintained by selection on clades, and (4) clade selection extends the explanatory power of the theory of evolution

Defining a Discipline: George Gaylord Simpson and the Invention of Modern Paleontology

Kearney studies how the paleontologist George Gaylord Simpson worked to define his own field of evolutionary paleontology

Biological Individuals

The impressive variation amongst biological individuals generates many complexities in addressing the simple-sounding question what is a biological individual? A distinction between evolutionary and physiological individuals is useful in thinking about biological individuals, as is attention to the kinds of groups, such as superorganisms and species, that have sometimes been thought of as biological individuals. More fully understanding the conceptual space that biological individuals occupy also involves considering a range of other concepts, such as life, reproduction, and agency. There has been a focus in some recent discussions by both philosophers and biologists on how evolutionary individuals are created and regulated, as well as continuing work on the evolution of individuality

Stephen Jay Gould and McLean v. Arkansas: Scientific Expertise and the Nature of Science in American Culture 1980–1985

Stephen Jay Gould was a Harvard evolutionary biologist who became a prominent media figure and commentator on evolution through the 1970s–1990s. In 1981 Gould was called as an expert witness on behalf of the plaintiffs in the court case McLean v. Arkansas. The lawsuit filed against the state claimed that a state law which mandated the teaching of creation science in Arkansas public schools was unconstitutional because it violated the Establishment Clause of the US Constitution. Therefore it was crucial for the plaintiffs to establish that creation science was not really \u27science\u27 but in fact a religious belief. Gould\u27s testimony along with other scientists, theologians and philosophers helped the plaintiffs win the case, which set a precedent for banning the teaching of creation science in public schools across the country