At the end of a thoughtful article on the future of nuclear war, Wiesner and York concluded that: "Both sides in the arms race are... confronted by the dilemma of steadily increasing military power and steadily decreasing national security. It is our considered professional judgment that this dilemma has no technical solution. If the great powers continue to look for solutions in the area of science and technology only, the result will be to worsen the situation.".

They are correct that punctuated equilibria apply to sexually reproducing organisms and that morphological evolutionary change is regarded as largely (if not exclusively) correlated with speciation events. However, they err in suggesting that we attribute stasis strictly to "developmental constraints," which represent only one of a set of possible mechanisms that we have suggested for the causes of stasis. Others include habitat tracking and the internal structure of species themselves [for example, (2)].

n one of the numerous movie versions of A Christmas Carol , Ebenezer Scrooge, mounting the steps to visit his dying partner, Jacob Marley, encounters a dignified gentleman sitting on a landing. "Are you the doctor?" Scrooge inquires. "No," replies the man, "I'm the undertaker; ours is a very competitive business." The cutthrought world of intellectuals must rank a close second, and few events attract more notice than a proclamation that popular ideas have died. Darwin's theory of natural selection has (...) been a perennial candidate for burial. (shrink)

Darwin's theory of evolution by natural selection provided the first, and only, causal-mechanistic account of the existence of adaptations in nature. As such, it provided the first, and only, scientific alternative to the “argument from design”. That alone would account for its philosophical significance. But the theory also raises other philosophical questions not encountered in the study of the theories of physics. Unfortunately the concept of natural selection is intimately intertwined with the other basic concepts of evolutionary theory—such as the (...) concepts of fitness and adaptation —that are themselves philosophically controversial. Fortunately we can make considerable headway in getting clear on natural selection without solving all of those outstanding problems. (shrink)

Ecological fitness has been suggested to provide a unifying definition of fitness. However, a metric for this notion of fitness was in most cases unavailable except by proxy with differential reproductive success. In this article, I show how differential persistence of lineages can be used as a way to assess ecological fitness. This view is inspired by a better understanding of the evolution of some clonal plants, colonial organisms, and ecosystems. Differential persistence shows the limitation of an ensemblist noncausal understanding (...) of evolution. Causal explanations are necessary to understand the evolution by natural selection of these biological systems. †To contact the author write to: Department of Philosophy, University of Montreal, P.O. Box 6128, Station Centre‐Ville, Montreal, Quebec, H3C 3J7 Canada; e‐mail: [email protected]. (shrink)

The diversity, complexity and adaptation of the biological realm is evident. Until Darwin, the best explanation for these three features of the biological was the conclusion of the “argument from design.” Darwin's theory of natural selection provides an explanation of all three of these features of the biological realm without adverting to some mysterious designing entity. But this explanation's success turns on the meaning of its central explanatory concept, ‘fitness’. Moreover, since Darwinian theory provides the resources for a purely causal (...) account of teleology, wherever it is manifested, its reliance on the concept of ‘fitness’ makes it imperative that conceptual problems threatening the explanatory legitimacy of this notion be solved. (shrink)

The diversity, complexity and adaptation of the biological realm is evident. Until Darwin, the best explanation for these three features of the biological was the conclusion of the “argument from design.” Darwin's theory of natural selection provides an explanation of all three of these features of the biological realm without adverting to some mysterious designing entity. But this explanation's success turns on the meaning of its central explanatory concept, ‘fitness’. Moreover, since Darwinian theory provides the resources for a purely causal (...) account of teleology, wherever it is manifested, its reliance on the concept of ‘fitness’ makes it imperative that conceptual problems threatening the explanatory legitimacy of this notion be solved. (shrink)

The concept of fitness began its career in biology long before evolutionary theory was mathematized. Fitness was used to describe an organism’s vigor, or the degree to which organisms “fit” into their environments. An organism’s success in avoiding predators and in building a nest obviously contribute to its fitness and to the fitness of its offspring, but the peacock’s gaudy tail seemed to be in an entirely different line of work. Fitness, as a term in ordinary language (as in “physical (...) fitness”) and in its original biological meaning, applied to the survival of an organism and its offspring, not to sheer reproductive output (Paul ////; Cronin 1991). Darwin’s separation of natural from sexual selection may sound odd from a modern perspective, but it made sense from this earlier point of view. (shrink)