Robert N. Brandon, Concepts and Methods in Evolutionary Biology (Cambridge: Cambridge University Press, 1996)
Brandon considers the proper philosophy of biology to be what he calls “mechanistic” as opposed to “holism” or “reductionism”. In essay number one, Brandon introduces what has become known as the propensity interpretation of fitness, or what he calls “adaptedness”. Brandon notes that most, if not all philosophy of biology today, accepts the basic writings of the propensity do regarding fitness. He has a number two, Randy contends that a mechanistic, selection based etiological account of “teleology” in biology is the correct method of explaining apparent teleology in biology.
CHAPTER 1: “adaptation in evolutionary theory”, three–29.
Definitions of things are thought to be either descriptive or steep…. Descriptive definitions merely described the meaning of terms already in usage, whereas stimulative definitions actually assigned, by stipulation, special meaning to a term, which could mean newly coined or simply co-opted (four). I, BRADFORD, hope to––in my dissertation––develop and extend stimulative usages of the terms employed therein, NOTE.
Brandon focuses on intraspecific, intraenvironmental selection in this paper––that is, natural selection with reference to individual organisms and not regarding that of populations. Brandon list three conditios/attributes that are critical components of the Darwinian theory of evolution:
#1: variation: there must be significant variation in morphological, physiological, and behavioral traits among members of a species.
#2: heredity: some traits are heritable so that individuals resemble their relations more than they resemble unrelated individuals, and in particular, offspring resemble parents.
#3: differential fitness: different variants leave different numbers of offspring in immediate or remote generations (five–six).
* For an excellent resource regarding the reception of Darwin’s theory, see David Hull 1973.
The theory of evolution by chance, so to speak, often called non-Darwinian evolution, or better: neutrality theory, is discussed well in King and Jukes 1969.
Neutrality theory supposes that certain alternative alleles are functionally equivalent, as they code for the same amino acids, and yes are selectively neutral (remember: there are 64 codons, but only 20 amino acids, so there is some redundancy in the coding).
Darwin’s “struggle for existence” in his natural selection theory, in its broadest sense refers to the individual struggle with his environment and with other individuals, resulting in certain traits rendering some organisms better fit/adapted to its environment than conspecifics with certain other traits (nine).
According to Brandon, the relational concept of adaptedness (that is, Brandon stone for fitness) is the funnel all of illusionary theory (11).
END of chapter 1.
CHAPTER 2: “biological teleology: questions and explanations”, 30–45.
According to Brandon, “how” and “why” are––at least in English––fairly reliable indicators of questions calling for explanations and “what” is a fairly decent indicator of questions not calling for explanation (31).
Brandon distinguishes between two types of evolutionary theories in this essay: one) functional biology; and two) evolutionary biology (a distinction first made by Ernst Mayr 1961). Meyer, 1961, notes that the “ever repeated question” of the functional biologist is “how?”, Whereas evolutionary biologist differs in both method and problem of interest, and hence ask, “why?”.
One set of question seeks what Meyer calls “proximate” causes, whereas the other set of questions 60 evolutionary or “ultimate” causes of the phenomena (cross-reference Ernst Mayr, 1961). According to Brandon, Ernst Mayr’s distinction marks the fundamental division of biology (33). However, Brandon’s present paper focuses on the division within the evolutionary theories, that is, a division between theological and nonteleological evolutionary theories (33).
According to Brandon, “what–for” questions are apparently teleological, and can be characterized also by “why?” and “how come?” (33). Conceptions of geology and biology, according to Brandon, have a “checkered” history, yet they haven’t died because of naturalists have felt that some sort of answers to teleological questions are necessary for a full understanding of biological phenomenon. According to Brandon, most biologists and philosophers of biology agreed that Darwinian answers to “what–four” questions are legitimate. Brandon acknowledges that there is still considerable controversy regarding terminology among biologists and philosophers of biology, particularly regarding whether or not the word to analogy––with all of his Aristotelian connotations––should be used at all, or if we should drop that term for something like “teleonomy” Brandon goes on to claim that Ernst Mayr himself would object to the “what–four” terminology that Brandon himself uses (footnote 9, page 43).
Brandon claims that some biological questions cannot be satisfactorily answered without appeal to the evolutionary processes that produce the items in question (34). Teleological language, according to Brandon, has received inconclusive scrutiny from biologists. He says that it is in fact the failure–or careless–to fail to make a distinction between the products of physical (that is non-teleological) and biological (that is teleological) evolution (34).
Brandon uses “physical” evolution is a catchall phrase referring to chemical, geological, stellar, small-scale, and large-scale evolution. Brandon characterizes physical evolution as the “survival of the stable”, whereas what he terms biological evolution refers to genetically evolving organisms that have variation and differential survival; Brandon focuses herein on biological not physical evolution (34).
Typically, according to Brandon, natural selection takes on the character has because of limitations on environmental resources, a phenomenon that Darwin referred to as “struggle for existence” (cross-reference page 35).
In biological evolution, the amplification of the effect of natural selection takes place in two steps: one) a severe limitation on environmental resources can generate a massive difference between reproductive success and failure, due merely to a small biological difference in species; two) due to the multiplicative nature of reproduction, defect but in small veritable differences in fitness can accelerate the rate of evolution over a number generations (35).
According to Brandon, the proper objects of “what-for” questions are “adaptations” (page 36). Brandon contends that biologists have made a mistake––far too frequently––of defining natural selection simply as different reproduction, but this is necessarily wrong but calls on that definition, one cannot distinguish evolution by natural selection and evolution by chance (that is, for example, random drift) (page 36). According to Brandon, natural selection should be defined as differential reproduction which is due to adaptive superiority of those organisms leaving more offspring (37).
Natural selection acts directly on phenotypes, not genotypes or genes, so this means that fitness is an organismic property, not a genetic property. However, it is not useful, according to Brandon, to talk about whole phenotypes as adapatations (page 37).
Some authors––for example Roose 1971, Nagel 1977, and months in 1971––argue that a trade is an adaptation if it is beneficial to its possessors.
According to Brandon, if the generally accepted theory of speciation is correct, then random drift in small populations (that is the founder effect) has had tremendous evolutionary effect over time. In fact, major differences among species are largely due to chance, and natural selection simply fine tunes these given differences to fit local environments (38). Note, BRADFORD, pleiotropic genes.
Adapatations or phenotypic traits that have evolved as a direct result of natural selection (40). When a biologist asked “what dashboard” questions, he postulates that is an adaptation, and then tries to discover it’s “adaptive significance” (or its “function”), which is what it was selected for (41). Upon seeing a trait, it is best to observe it in the modern setting to see how it interacts with the rest of the phenotype, and after that, one can reverse extrapolate into the past to derive a plausible sonority of force derivation, that is, the manner in which the trait may have evolved due to its positive effects on his possessor; if one is doing with an extinct organism, the process is not much different, but there is more reconstruction to do.
Put abstractly, a “what for? Asked of adaptation capital a is answered by signing the effects of past-instances of A (or precursors of A) and showing how these effects increase the adaptedness of A’s possessors (or the possessors of A’s precursors) and so led to the evolution of A” (41). According to Brandon, in view of this fact, the sense in which what–four questions and their answers are teleological canal be clarified: in essence, trait A’s existence is explained in terms of what A does; more fully, A’s existence is explained in terms of effects of past instances of A; but not just any effects––one slice only those effects that are relevant to the fitness of possessors of A (41).
According to Brandon, what–four questions demand teleological explanations as answers; moreover, what may be called neo-Darwinian theory of adaptation or the theory of evolution by natural selection is teleological in that it answers what-for questions, or is evolution by chance/random drift (à la Gould) is not teleological (41–42).
According to Brandon, the theory of adaptation is the best developed, and perhaps the only developed to the logical scientific theory (42). It seems to me, BRADFORD, the Brandon would explicitly support identifying the adaptation dependent theory of natural selection, then, as teleological. The reason that Brandon uses the term “today logical” instead of, say, “teleonomy” is because he thinks adaptation explanation’s doing fact satisfactorily answer teleological questions (42).
As an example of his proposed adaptation explanations, Brandon refers to how some species of birds regulate their clutch size––that is, the number of eggs laid––which seems to be counterintuitive to the view that one should procreate as much as is possible. One explanation of this phenomenon is that they do it for the good of the species as a whole, a view that was popular until recently; however, an alternative––and preferable––explanation is what Brandon refers to as adaptation–explanation which states that there is an optimal plot size for birds in a given population, and laying either more or less than this optimum results in fewer viable loss bring in the next-generation, which has been experimentally confirmed (cross reference Lack, 1954). Thus, birds regulate their clutch size further “own” good and by doing so, their fitness is increased. This is a clear example of how certain phenomenon in the world “cry it out” for geological explanations, for without them our understanding would be incomplete (42).
For good example of how physical evolution led to, or evolved into, biological evolution, see Dawkins 1976, chapter 2.
For a definition and discussion of relative adaptedness and natural selection, see Brandon 1978.
Brandon posits an interesting counterfactual in his endnotes to this chapter: if Aristotle had been convinced of the truth of Darwinian evolutionary theory, then you would have found such explanations totally adequate as answers of two teleological questions (footnote 25, page 45).
CHAPTER 3: a structural description of evolutionary theory, 46–57.
One should not supposed that there is a uniquely correct structural description of evolutionary theory, and one should also not suppose that giving a structural description of evolutionary theory is essentially uncovering what is implicit in biological work (46).
Brandon states that the terminology of “evolutionary theory” is often used in an ambiguous way to in fact cover a whole cluster of interrelated theories in evolutionary biology, including theories of speciation, population genetics, and evolutionary ecology; but Brandon distinctly uses the terminology to refer to the theory of natural selection that sees 46).
The Darwinian theory of evolution posits a particular mechanism of evolution, namely the difference reproduction of heritable variation (46–47). Natural selection, then, is the name of the explanatory mechanism of dolmen in evolution (47), the mechanism of which is composed of three parts: one) variation; two) heritability; and three) differential reproduction. The focus of the Darwinian theory of evolution is “differential reproduction” not the other two, though they are important (47).
Brandon’s chapter herein is devoted to explicating the role of natural selection and evolution is (48). Brandon claims that the principle of natural selection is an explanatory principle; further, he claims that differential fitness/adaptedness explains differential reproduction (48). So then, adaptedness explains reproductive success. The notion of different reproductive success is equivalent to differential “fitness” (48). Natural selection explains differential fitness, according to Brandon (48). For the explanatory relation, Brandon uses the word adaptedness (48). According to Brandon, however, adaptedness is not fitness per se, but is related to fitness––or reproductive success––in much the same way that solubility is related to dissolving (49). Brandon treats adaptedness, in this chapter, as a probabilistic disposition, or a propensity toward something (50).
In Brandon (1978), he presents the core of evolutionary theory as the principle of natural selection, appraisal itself without empirical content; at the periphery of the theory lie instantiations of the principle which are in fear cool biological statements that are specific to particular populations in particular environments (52).
Branding contends that although the principle of natural selection has no empirical biological content it self, the presuppositions of its applicability are empirical, the statement of which forms the empirical biological core of evolutionary theory; Brandon sees two basic claims: one) biological entities are chance setups with respect to reproduction; and two) there are cases where biological entities in a given environment differ in their adaptedness to that environment (53). Regarding claim number one, the term “chance set ups” is Ian hackings (1965, page 13), and he notes that the proverbial trial is the entity’s life itself. Regarding claim number two, some entities differ in their expected fitness values; note the differences in fitness neither imply or implied by differences in adaptedness––that is, expected fitness values (53). On the propensity interpretation of probability, and expected that this value is the dispositional property (53).
As a result of claims number one and two above, branding contends that adaptedness “is to a degree heritable, or equivalently, the causal bases of adaptedness values are to a degree heritable” (56).
CHAPTER 4: levels of selection, 58–65:
in this chapter, Brandon distinguishes between “fitness” and “adaptedness” in that fitness is the actual reproductive success and adaptedness is the expected reproductive success (58).
Brandon contends that natural selection is the differential reproduction of biological entities which is due to the differential adaptedness of those entities to a common environment (cross-reference Brandon 1978, and 1981). Brandon contends, then, that group selection is a difference reproduction of biological groups which is due to the differential adaptedness of those groups to a common environment (61).
CHAPTER 8: the levels of selection: a hierarchy of interactors, 124–143:
evolution by natural selection requires both limited the variation and the underlying genetic variation. The interaction of the phenotype with the environment causes differential reproduction, and thereby leads to a differential replication of genes, which, through ontogeny, leads to a new tentative distribution ad infinitum (cross-reference page 125).
So then, evolution by natural selection is a two-step process, with step one involving the replication of structure, instead to involving some interaction with the environment so that replication is differential; the entities functioning in the second step are typically called phenotypes, although David L Hull (1980, page 318) suggest the term “interactor” which he defines as the entity that directly interacts as a cohesive whole with this environment in such a way that replication is differential close scratch that.
According to Brandon, the theory of evolution by natural selection is the only theory we have got that can explain the origins and the maintenance of adaptations. Contrary to previous assertions in biology and philosophy of biology, Brandon does not think it to be the case that all selection must be beneficial to organism, NOTE.
CHAPTER 11: reductionism versus holism versus mechanism, 179–204.
Philip Kitcher (1984) notes “the history of biology is marked by continuing opposition between reductionist and anti-reductionists. Reductionism thrives on exploiting the charge that it provides the only alternatives to the mushy incompressibility of vitalism. Anti-reductionist reply that their opponents have ignored the organismic complexity of nature” (1984, 369).
In this chapter, Brandon argues that the above-mentioned long-standing disagreement is based on a confusion between reductionism and mechanism. He thus argues that the opposition between reductionism and holism is a false choice, and neither of these options should be endorsed. Brandon hopes to show, further, that contemporary biology is, and in fact should be, largely mechanistic (179–180). Brandon supports the causal/mechanical model of exclamation, and according to it, to explain some phenomenon one needs to show how it was causally produced, that is, to uncover the causal mechanism that produced it. According to this view that Brandon agrees with, there is a tight linkage between one’s ontological view and one’s view of proper explanation (cross-reference Wesley Salmon 1984, 1989). Francis crick (1994, 277-78) defines reductionism as the “idea that it is possible, at least in principle, to explain the phenomenon in terms of less complicated constituents…[and is the] main method of explanation used by the exact sciences”.
In the classical Defense of reductionistic evolutionary biology, G.C.Williams (1966) argues that all evolution can be understood in terms of forces acting at the level of individual genes. Francis crick (not 94) thinks the stopping point for biologists is the level of atomic chemistry.
To understand the rise of holism and 20 is entered biology, according to Brandon, one must look to Descartes, who thought there was a fundamental difference between humans and other animals––as in addition to being machines, humans also had souls (or minds) (183). Within biology challenges were raised a Cartesian dualism from the beginning, but it was Charles Darwin who dealt the decisive deathblow: the theory of evolution by common descent made it highly implausible that man––and only man!––Have a soul; and as a result of Darwin’s theory, Cartesian dualism was no longer scientifically plausible after 1859. Indeed, the mutual incompatibility between the two presents what Laudan (1977) calls a conceptual problem, a conceptual problem that gave rise to the philosophical controversies of the 1920s and 1930s that led to the articulation of 20th-century holism (184).
J.C.Smuts and J.S.Haldane (father of J.B.S. Haldane, the geneticist) were two of the leading figures in the rise of holism in the 1920s. In his book Holism and Evolution (1926), Smuts coined the term “holism”. Haldane promoted a few similar to smuts, and after reading holism and evolution, he adopted smuts usage of the term holism to describe his own views (184).
NOTE Bradford: I need to research JC smuts and JBS Haldane further, as they promote ideas that are seemingly correlative of the emergence theory.
Smuts stressed that the whole is more than the sum of its parts, but not something added to those parts (counter vitalism), writing: “a whole is not a tertium quid over and above the parts which compose it; it is these parts in their intimate union and the new reactions and functions which result from that union” (smuts, 1926, page 122).
According to Brandon, the primary object of holism and evolution was to explain how evolution can be creative, that is how power levels of whole (for example, life) can emerge from lower levels (for example, matter). Like Haldane, smuts argued that the synthesis supports in the wholes changes those parts so that they no longer function as they would in isolation (185). Holists claim that the parts of wholes are interconnected in such a way that they cannot be studied in isolation––at least not if one wants to know how they behave in the whole (page 186).
Strong reductionism is at least as guilty of imposing a priori metaphysics on science as is holism, according to Brandon (189). Brandon in fact says that in biology, especially in evolutionary biology, he cannot think of a single example of someone holding to a strong methodological reductionists position, although he does acknowledge that Williams (1966) and Dawkins (1976) do come rather close to it.
With reductionism is much more plausible, according to Brandon (189). As an ontological thesis, this idea seems to presuppose that causation in a world always works bottom-up (regarding hierarchical levels; page 189). However, causation biology sings rarely to exclusively follow the bottom of which reductionistic model (189). According to Brandon, the ambiguity and openness of this proposed mechanistic thesis as opposed to either pure holism or pure reductionism is a virtue (192–193). He identifies the following as examples of mechanisms in nature: one) mutations; two) drift; three) migration; four) selection; and five) population structures (193). He contends that mechanism plays a normative role in evolutionary biology (196), and that in fact it should. Brandon argues that an “ideally complete adaptation” explanation has five components: one) evidence that selection has occurred on the relevant traits; two) ecological explanation of that selection (ecological as in global); three) an account of the underlying genetics of the traits (that is, they are heritable); four) information on population structure (for example, gene flow and heterogeneity); and five) phylogenetic information on trait polarity (that is, what traits are evolutionarily primitive and which are derived) (197).
END of review of book; see bibliography for further reference.in Evolutionary Biology (Brandon)