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Emanuele Serrelli - Pitfalls and Strengths of Adaptation in Biology Education

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Conference talk
Serrelli E (2011). Pitfalls and strengths of adaptation in biology education: how can philosophy of science help. 4th Sydney-Tilburg conference on the philosophy of science “The authority of science”, Sydney (Australia), 8-10 April.

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Emanuele Serrelli - Pitfalls and Strengths of Adaptation in Biology Education

  1. 1. Pitfalls and strengths of adaptation in biologyeducation: How can philosophy of science helpEmanuele Serrelli“Riccardo Massa” Department of Human SciencesUniversity of Milano Bicocca, Italy 1
  2. 2. Education Authority Nature Of Science (e.g. Bell et al. 2001) SCIENCEAIM: a particularphilosophically-informed educationalfocus that goes in the of biologydirection ofemphasizing, Philosophyincreasing, and of sciencemaintaining theauthority of science. H P S 2
  3. 3. OUTLINE• Why and how HPS studies are called into play in biology education (ex. “laboratory”). NOS-HPS alliance• Some bits of analysis of adaptation in philosophy of biology• Back to biology education: Worries rised by conceptual analysis (including those about the authority of science) and HPS answers currently adopted• Underestimated roles for philosophy of science: skills for scientific definition• Conclusion 3
  4. 4. (c) Photos by Franca Lasagna, 2009McComas WF, ed. (2006). Investigating evolutionary biology in thelaboratory. National Association of Biology Teachers (NABT), Kendall-Hunt. 4
  5. 5. McComas WF, ed. (2006). Investigating evolutionary biology in thelaboratory. National Association of Biology Teachers (NABT), Kendall-Hunt. 5
  6. 6. • McComas (2006) showed how HPS is useful for structuring the labs.• For example, the collection relied on a large body of analyses in philosophy of biology, providing the logical structure (fundamental logics and concepts) of the Darwin-Wallace model of natural selection as a series of interdependent assertions that work together but can be isolated and understood as individual components. The two most important: descent with modification (furthermore divided in ten scientific assertions) and natural selection (furthermore divided in five). Examples: differential survival, adaptation, convergence- divergence, common descent, principles and difficulties of systematics and biological classification.6
  7. 7. • Plus, labs are said to portray the nature of science. • students construct new meaningful concepts and generate “if...and...then...therefore” arguments and hypothetico-deductive inferences, managing “ideas that work extremely well at explaining the natural world in naturalistic terms we can understand, making accurate predictions, and guiding further empirical research” (Clough, p. 72) • laboratory “learning cycles” teach the students that “debate, rethinking, and a cycle of verification are important elements of the scientific endeavor and, as such, are inherent in healthy scientific discourse” (McComas, p. 21).7
  8. 8. • So, labs realize the most fundamental claims of NOS as a field of study: • «Students have to become scientific, not just learn science» (e.g. Matthews 1994, p. 25; but well before, Dewey 1916).• Laboratories are described as inspired to HPS studies, and conversely as a context in which it is possible (and important) for students to discuss and understand HPS (e.g. how natural selection was discovered, or what’s to be intended by “scientific law”).8
  9. 9. • Constructivism revised: concepts are necessary in science education (as they are in science, after all). • Most constructivists recognize that there is a public, symbolic, created world of science and mathematics that children have to be introduced to, and whose concepts they have to internalize. They recognize further that children are not going to discover this world, its concepts and their relationships, merely by private inquiry [...]. This recognition is a major departure from individualist [AND INDUCTIVIST] constructivism where students create their own knowledge claims [Matthews MR (1994). Science teaching. The role of history and philosophy of science. Routledge, p. 155].• Even in student-led learning methods, teachers are are not going to avoid giving concepts and definitions.9
  10. 10. • Points of incidence for POS on science education: • a general view of science [e.g. as an active, circular, and self-corrective process] • the modularization of overarching theoretical structures [e.g. to allow for laboratories] • the refining of concepts and definitions• «The intricacies of biological terminology, reflecting the complexity of organisms themselves, are a ready source of semantic confusion» (Ghiselin 1966).10
  11. 11. • Adaptation is a finalistic term• It was inherited and co-opted by Darwin • We see these beautiful co-adaptations most plainly in the woodpecker and missletoe; and only a little less plainly in the humblest parasite which clings to the hairs of a quadruped or feathers of a bird; in the structure of the beetle which dives through the water; in the plumed seed which is wafted by the gentlest breeze; in short, we see beautiful adaptations everywhere and in every part of the organic world [Darwin 1859, Chap. III Struggle for existence, pp. 60-61].• Adaptation is an observable state of things. It can also be referred to particular traits (hence the plural form: adaptations).11
  12. 12. • In addition to the state, Darwin’s book marked the appearance of a natural process as a cause of observed adaptation • […] it could be shown how the innumerable species inhabiting this world have been modified, so as to acquire that perfection of structure and coadaptation which most justly excites our admiration (Darwin 1859, Introduction, pag. 3).• Hence the verbal form, with NS as the subject: • Natural selection [...] will adapt the structure of each individual for the benefit of the community; if each in consequence profits by the selected change (Darwin C., (1859), Chap. IV natural Selection, pag.82).12
  13. 13. • Retained finalism• State / process ambiguity• Active (NS, organisms) / passive (organisms) form • Induced “personization”13
  14. 14. • Martin M (1972), Concepts of science education. A philosophical analysis. Glenview-London: Scott, Foresman & Co.• Darwin might be doing an ANALYTIC RATIONAL RECONSTRUCTION • A rational reconstruction is to be evaluated [...] in terms of its ability to improve upon standard usages for scientific purposes. Depending on the inadequacies of standard usage for scientific purposes, a rational reconstruction will depart more or less from a reportive definition (p. 79).14
  15. 15. • Retained finalism• State / process ambiguity• Active (NS, organisms) / passive (organisms) form • Induced “personization”• Adaptation splits: • species: processual meaning is added • individual: “more or less adapted” (to become fitness) • character (trait)• Not perfect15
  16. 16. • Ghiselin (1966)• “Adaptation” is «used for several different concepts» (p. 148) but «useful in discussing many types of relationships» (p. 153) => retained.• The state/process ambiguity leads to «misuse, nonsense and paradox». «“An animal is adapted” suggests that an animal has adapted».• Trouble purifying the state and organism meaning (with “fitness” as a benchmark word).16
  17. 17. • Blurred and unstable delimitation: • When someone says that species x is better adapted to its environment than species y, he means something like this: if his evaluation of the conditions is correct, then the probability that x will survive is greater than the probability that y will survive. (149) • When we say that an organism becomes more adapted to its environment, we mean that it becomes so modified that the likelihood of becoming extinct in that environment is decreased (149).17
  18. 18. • Probabilistic nature of this state called adaptation: • it is a big mistake to consider adaptation an intrinsic property, or an actual condition, of the relation between organism and environment • crude and unphilosophical empiricists • «we have no right to assume that there have ever existed nonadapted or ill-adapted organisms, for these would not have been viable. Even the most simply organized living things are ideally adapted to their specific environment. Types in which the new adaptation to a changed environment has not been sufficiently successful have obviously died out». • nominalistic metaphysicians • «probabilistic entities are not real»18
  19. 19. • Environment has to be intended in statistical terms as well: • «By environment we do not mean only those parts of the universe with which an organism is interacting, but we refer to the class of entities with which it is likely to interact» (150).• In conclusion: • «When one conceives of both “adaptation” and the “environment” as statistical, population concepts, the sophistical nature of certain arguments becomes obvious» (150).19
  20. 20. • George C. Williams (1966), Adaptation and natural selection • to avoid «serious errors» in evolutionary biology we should restrict the use of the word adaptation to traits whose genetic basis is demonstrably due to functional selection • «The only adaptations that clearly exist express themselves in genetically defined individuals and have only one ultimate goal, the maximal perpetuation of the genes responsible for the visible adaptive mechanism» (Idem, pag. 252). • We ought to «take the theory of natural selection in its simpliest and most austere form, the differential survival of alternative alleles, and use it in an uncompromising fashion whenever a problem of adaptation arises» (Idem, pag. 270).20
  21. 21. • Gould & Vrba (1982) • They share the structure/function/ effect problem • They can make no use of William’s population genetics definition of the process • Adaptation at a larger scale (vs. extrapolation), as “tinkering”: «Novelties come from previously unseen association of old material. To create is to recombine» (Francois Jacob, “Evolution and tinkering”, 1977)21
  22. 22. • Retained finalism• State / process ambiguity• Active (NS, organisms) / passive (organisms) form • Induced “personization”• Adaptation splits: • species: processual meaning is added • individual: “more or less adapted” (to become fitness) • character (trait)• Not perfect• Effect/function/structure interplay• Continuous transformation vs. recombination• Disciplinary definitions• PLUS gene in relation to phenotype (Lewontin, Rose & Kamin 1984), organism-environment boundary (Oyama 2000; Oyama, Griffiths & Gray 2001; Pigliucci & Muller 2010).• ...22
  23. 23. • Philosophers may be perfectly comfortable with this situation • Ghiselin’s extreme position: «It is utterly irrelevant that improper usage, intentional or otherwise, may give rise to absurdities» (p. 153). • Many problems are «mere pseudo- problems to those fully aware of the dangers» (p. 147).• But is it irrelevant for biology education? Philosophy reliable guide to scientific concepts for scientific understanding?• Also the problem of the perceived authority of science?23
  24. 24. • Historical way out? • Only when students understand how science functions and how scientific knowledge is generated can they truly appreciate, understand and value science itself […]. One potentially fruitful approach in sharing important elements of the nature of science may be found in the use of history of science in order to provide instruction in how science functions (Kampourakis & McComas 2010, pp. 638-9).• History should: contextualize + explain + improve appraisal of the nature of science + of the value of science24
  25. 25. • In “Epistemology and the teaching of science” (Nadeau & Désautels 1984) the aim of HPS in education was to “dispel the myths” about science Myth Pedagogical action scientism naive realism neutralization blissful empiricism attenuation credulous experimentalism elimination blind idealism denunciation excessive rationalism eradication 25
  26. 26. • Today the list of myths is updated (McComas 1998, 2006, 2008).• However, exposing the historical reasons for the logical and terminological tragedy of adaptation answers many myths, but doesn’t necessarily offer a trustful happy end.• To be fair, stories do partly answer the question “where does the authority of science come from?”, by showing the “hard work” of biology, but philosophy of science has other cards to play.26
  27. 27. Martin’s (1972) argument on scientific definitions• All science educators and textbooks define terms and use definitions• And, yes, «science teachers have the responsibility of conveying the precise meaning of scientific terms in actual scientific practice» (p. 92); on the other hand, «it is far better that the students either receive or discover definitions that they can understand, even if these definitions are far from accurate» (p. 93).• “Defining activity” (p. 76) is an actual, integral part of scientific practice (as the example of adaptation shows). 27
  28. 28. Martin’s (1972) argument on scientific definitions• «Usually there is no special emphasis on developing the skill of defining in the training of scientists [...]. As in any activity, skill is best achieved through systematic practice under the guiding hand of a teacher who has already mastered the skill. It is to be hoped that such systematic training will become part of science education» (p. 94, my emphasis). «As the science student matures, the science teacher can not only covey the meaning of scientific terms via definitions to the student, but also teach the student how to define scientific terms and evaluate definitions» (p. 93, my emph.).• Some methodological ways to educate such a skill in the classroom: the use of “stipulative definitions” (p. 93), explicit discussions on definition in biological science before studying particular definitions (p. 90), and exercise reciprocal criticism (p. 93). 28
  29. 29. Martin’s (1972) argument on scientific definitions• Martin does a useful taxonomy of definitions, but the point is that this is probably an essential matter for philosophy of science: What does it mean to define, what kinds of definitions there are... Multiple meanings and meaning change emerge as constitutive to science.• Yes, there probably will be internal HPS disagreements but there is a reasonable consensus on some topics, and maybe novel synergies or tradeoffs may emerge if a responsibility towards science education is adopted. 29
  30. 30. Conclusion (or: a particular philosophically-informed educational focus)• The authority of science comes from features like “scientific definitions” (clarity, univocity...) but perhaps more from the related skills, like those involved in the “defining activity”. These skills can probably be learned (although normally they do not receive the proper attention in the curriculum), and philosophy of science can have here a further, important access point. My supposition is that the perspective of learning scientific skills in science education may support the authority of science.• Frederick Aicken, The nature of science (1984): • ...there is nothing new in a drift towards the irrational, it is reassuring that the work of scientists continues to move stubbornly in the opposite direction. Science seeks to create order from disorder, to find some rational meaning in the apparently meaningless, to oppose the natural tendency towards chaos [...]. It is the skill of makinf use of the knowledge, not the knowledge itself, which matters (pp. 121, 139). 30