Book+Summery+and+Analysis+of+Refiguring+Life+by+Evelyn+Fox+Keller

//Refiguring Life: Metaphors of Twentieth-Century Biology// by Evelyn Fox Keller This book is an examination of how language, metaphor and technology have shaped the history of genetics, and the question of what role language plays in science. However, in her own words, Keller admits that “not all metaphors are equally useful or… equally captivating. The effectiveness of a metaphor…depends on shared social conventions and, perhaps especially, on the authority conventionally granted to those who use it.” Just as it also depends on what metaphors are already conventionally used and on the technology available at that time. The book is divided into three sections which address, firstly, language and science, namely the discourse of gene action and the gene as seen by Erwin Schrodinger, as “law-code and executive power -…architect’s plan and builder’s craft – in one.” The second part, titled //Molecules, Messages, and Memory: Life and the Second Law//, traces the history of metaphors from Maxwell’s “Demon” to “code-script” introduced by Schrodinger to try to understand and to answer the question of what gives genes their power. The last section is devoted to the changing metaphor of the cell and the organism as a machine and a computer – or a multiple input-multiple output transducer. The first section begins with a brief historical account of the history of genetics beginning with Mendel, who was rediscovered in 1900, which led to crucial changes in biology. “…in 1902 Mendelian ‘factors’ were tied to chromosomal structures; the term //genetics// was coined in 1905 and //gene// in 1909. In 1915 T.H. Morgan published //The Mechanism of Mendelian Heredity//; in 1916 the first genetics journal was founded…” This change led to the emergence of two new disciplines of biology – genetics and embryology – in which the study of transmission (the chromosome) became the focus of genetics, and development (the role of the cytoplasm) became the domain of embryology. The geneticists of Morgan’s school of thought assumed that the gene must lie at the heart of development – meaning that the gene is the primary agent of development – and so the cytoplasm was a passive substance almost entirely under the influence of gene action. But most importantly, the geneticists of Morgan’s school – the first generation of geneticists – “did more that develop the techniques and practice of genetics as a rival to embryology; they also forged a way of talking about genes – about their role and meaning in reproduction, growth, and development.” In my opinion, this ability to //talk// about their field of study – to have defined vocabulary – and to have the ability to communicate it, not just to the people in genetics but to others, was the reason for the popularity of genetics and the decline in popularity of embryology until the mid 20th century. It did not matter the no one really knew exactly what genes did or even what they were at that time, because those first generation geneticists “provided a conceptual framework that was critically important for the future course of biological research.” This framework provided the structure of discourse, questioning, valid experimenting and acceptable answers to some American geneticists who did begin to study development in the 1930s and further on, serving more than biological related functions, but “cognitive and political functions” as well. In 1940 George Beadle and Arthur Tatum proposed an explanation that answered the question that had puzzled geneticists decades earlier – how do genes produce their effects? Their model came to be known as the “one gene-one enzyme” hypothesis. This new hypothesis served to refocus developmental genetics as the biochemistry of gene action. Then in 1953 J.D. Watson and Francis Crick identified DNA as //the// genetic material, and provided the answer to how genes reproduce themselves (hydrogen bonding) and how they make enzymes (nucleic acid sequences). Finally, geneticists had the answer to all their questions. “DNA carries the ‘genetical information’ (or program), and the genes ‘produce their effects’ by providing the ‘instructions’ for protein synthesis. DNA makes RNA, RNA makes proteins, and proteins make us.” This model exists even today in most textbooks and was a supremely important realization for biology and for all the fields of science in general. However, there is a catch. DNA cannot ‘reproduce’ without proteins, but proteins are made by other proteins and hence there is an appearance of infinite regress. However, “we inherit not only genes made of DNA but an intricate structure of cellular machinery made up of proteins.” (as quoted from Richard Lewontin) This caused a shift to the discipline of embryology as a near equal to genetics because now the cytoplasm (especially that from the egg in development) is very near to the genome as the center of control. So why did embryology lag behind genetics? I would answer that it was because embryology lacked a discourse and sufficient metaphors to defend their position against that of genetics, and that the technologies available were not sufficient to do many experiments in development at that time, //and// that there was a reluctance to go into that field due to lack of popularity that resulted from the language used by geneticists that downplayed the importance of the cytoplasm in development. How science is talked about is almost more important and more influential than the actual scientific experiments! Hailed as the father of quantum mechanics, Erwin Schrodinger was also instrumental to the field of biology for his notion of the chromosome as “code-script”. “It is these chromosomes…that contain in some kind if code-script the entire pattern of the individual’s future development and of its functioning in the mature state.” However, it was the introduction of the 2nd Law of Thermodynamics that began the series of metaphors seeking to explain the thing which gives genes their power, and the question of what life is. The story starts with William Thomson (later Lord Kelvin) in his 1851 paper, “//On the Dynamical Theory of Heat//” in which he offers two possibilities for the exemption of living organisms from the 2nd Law: either heat “in the animal frame acts so as to produce mechanical effect, from some of the heat” or “the will of the animal can make these currents produce mechanical effect”. Later, Thompson concluded that if it was the will of the animal that kept it from decay, than the rest of the universe would eventually have to have an ending. Hermann Helmholtz, in coining the term //thermal death//, also warned that the universe is heading towards a state in which the temperature will be too low to permit life to exist. About fifty years later Ernest Rutherford stated, “Science offers no escape from the conclusion of Kelvin and Helmholtz that the sun must ultimately grow cold and this earth become a dead planet moving through the intense cold of empty space.” Then, in a letter to P.G. Tait in 1867, James Clerk Maxwell offered a possible solution – a being that could reverse the natural tendency towards decay. “Conceive a finite being who knows the paths and velocities of all the molecules by simple inspection but who can do no work except open and close a hole…then permits only fast molecules to pass from the cooler vessel into the warmer one, blocking the slower molecules… [Such that] ‘the hot system has got hotter and the cold colder and yet no work has been done, only the intelligence of a very observant and neat-fingered being as been employed’.” (Aka a Demon and later known as “Maxwell’s Demon”) Now of all the explanations that could be conceived, this is the most ridiculous. A being that is able to block a hole in some system that reverses the inevitability of thermal death is not answering the question but only making it more complex by //introducing another factor// (a ‘finite being’) into the equation. Maxwell’s Demon endured until the 1929 paper by Leo Szilard which effectively killed Maxwell’s Demon because it showed “that for a ‘biological system,’ the model of which was a piston operating in a one-dimensional gas, the Demon would in fact have to perform work in the process of measurement, thereby saving the second law.” The disagreements between vitalism (which its members insisted on a radical opposition between living processes and the second law) and mechanism (which denied the existence of any problem) hinged on whether the local accumulation of order was in violation of the second law or the only relevant question dealt with the global production of entropy. Schrodinger had a solution to this problem of how an organism avoids decay. “By eating, drinking, breathing and (in the case of plants) assimilating”. Therefore an organism does not violate the second law because it continually draws negative entropy from its environment. Schrodinger also solved the problem of multicellularity by rephrasing the question to one of communication, and offered two analogies (one military and one political). “…in every cell is to be found a representative (be it a soldier or a local government station) of the same code-script, the same ‘law-code and executive power,’ empowered by its progenitor to guide, control, and execute the construction and maintenance of the body under its immediate charge.” This metaphor of the DNA sequence in each cell can be seen as imperative to biology and persistent because of its usefulness. With the introduction of the computer, the meaning of many terms “- of //message//, of //information//, of //organization//, indeed of //organism// – have, over the last few decades, been transformed. Several new disciplines such as information theory, cybernetics, systems analysis, operations research, and computer science (and more recently the merging of biology and computer science to yield bioinformatics) have been created, along with a new conceptual vocabulary for dealing with them. Many of the qualities of the computer were borrowed and imported into biology, using “systems’ as a metaphor for organisms. During this period, the first definition of a system in modern technology was used by the U.S. Air Force, which used the definition of systems according to Webster as “a structure composed of distinct parts so constituted that the functioning of the parts and their relation to one another is governed by their relation to the whole.” It was then concluded that the Air Defense System is therefore an organism, an organism being defined as possessing “sensory components, communication facilities, data analyzing devices, centers of judgment, directors of action and effectors, or executing agencies.” Then in 1958 Francis Crick formulated what is known as the Central Dogma of molecular biology (another discipline influenced by the development of the computer): unidirectional causality. A “…linear structure of causal influence, from the central office of DNA to the outlying subsidiaries of the protein factory,” in which the term “information” was liberated from its cybernetic term and used in its colloquial meaning to describe genetic information contained in the nucleic acid sequences of DNA. Using this model of linear causality, it would be impossible for information to flow from proteins to nucleic acid. A counter example could be said to be the operon model of gene regulation in prokaryotes (where 3 enzymes are regulated as a single unit) discovered by Monod and Francois Jacob in 1961 which relies on a feedback from the system for regulation. This led to the conclusion that genes alone cannot be solely responsible to explain embryogenesis, and thus the entire organism must in some way be involved. This question has led to the study of developmental biology, which has become one of the prime research areas of biology, especially with the advent of new technologies the created new opportunities for cloning and sequencing (like PCR or polymerase chain reaction used to amplify short stretches of DNA sequences) that created an even tighter connection between biology and the information sciences. This merging led to another new metaphor that “among biologists [the computer] became widely accepted as a suitable model for the cell (or organism).” In conclusion, this book described the history of biology as it changed through time due to changing metaphors and emerging technologies. It also illustrated the importance of language and how it can break or make a new field of science based solely on how the science is talked about and the models that it uses. And it discusses the merging of biology with computers to create a new model for an organism – a computer or machine. And one asks, what does this mean for the future of biology and of humanity? This is a book that needs to be read several times because each time evokes a slightly different interpretation. It is a quick read, but by no means an easy one. While reading I made some connections to my classes this semester. In my biology class we discussed the characteristics of life – with potential answers including the capacity to reproduce, the ability to metabolize, an ability to grow and a response to stimuli. Another definition of life that I thought was even better came from this book and was Schrodinger’s answer. //The power of a living system to stave off death is what makes is living; not its capacity to reproduce, metabolize, etc but its ability to avoid decay.// Tying this into the //What is this science essay?// – Science is not just comprised of the experiments that are being done, but includes how the science is talked about. (This includes books and articles and specific vocabulary, and now includes press conferences and television shows.)