International Society for History, Philosophy, and Social Studies of Biology

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MONDAY, JULY 6  /  09:00 - 10:30  /  DS-R520
Organized session / standard talks
New perspectives on biological information

Brett Calcott** (Arizona State University, United States); Karola Stotz (Macquarie University, Australia)

The topic of biological information continues to captivate philosophers of biology. The aim of these two sessions is to showcase new research in this area, specifically (though not necessarily limited to) research on genes and gene action. In the view of many philosophers, crucial advances have recently been made in our general understanding of sign use and of causation. How can these theoretical advances be exploited to deepen our understanding of information and its causal and functional role in biological systems?

What makes causal relationships in biology "informational" relationships?

Karola Stotz (Macquarie University, Australia)

James Woodward has remarked that, “biologists tend to think of structures as carrying information when they are involved in causally specific relationships” (2010, 314). My collaborators and I agree, and think this needs documenting and explaining by analyzing key examples of biologists distinguishing information from non-information. One example is Crick’s use of the idea of information to state the Central Dogma and sequence hypothesis. Crick believed that three factors were involved in protein synthesis, “the flow of energy, the flow of matter, and the flow of information” (1958, 144). I will elucidate the epistemic payoff of introducing information in this context. Another example is the distinction sometimes drawn in developmental biology between ‘instructive’ and ‘permissive’ causes (Gilbert 2003). I will show how the distinction between informational and other causal processes does real explanatory work and how it flows naturally from the pre-existing concept of information. Previous attempts to do this have focused on the analogy between aspects of biology and signaling systems. I argue that the analogy between biological information and human signaling points to an objective property of causal structure, and that it is this structure that justifies picking out some causal processes as informational. The work presented constitutes an explication of the idea of information, which maintains intellectual continuity with a vernacular concept but is prepared to depart from the original concept when this serves the goal of understanding the distinctive nature of living systems.

Biological specificity and biological information

Arnaud Pocheville (University of Sydney, Australia)

In recent years a number of information theorists have constructed information theoretic measures of causal influence. In earlier work my collaborators and I have constructed such a measure designed to give a quantitative account of causal specificity. Here I give an overview of these measures and show how this apparatus can be used to analyse the linear or ‘informational’ specificity between nucleic acids and their products, and also the specificity of regulatory RNAs. A different set of information theoretic tools have been used by biologists to analyse the stereochemical specificity between biomolecules. I examine the relationship between these two projects. Amongst other connections, these two information-theoretic approaches to specificity are related by the fact that stereochemical specificity can be encoded and transmitted as linear specificity.

Crick information: In genomes and elsewhere

Paul Griffiths (Sydney University, Australia)

Francis Crick’s “sequence hypothesis” proposed “that the specificity of a piece of nucleic acid is expressed solely by the sequence of its bases, and that this sequence is a (simple) code” (1958, 152). Crick was right. However, most gene products are not fully specified in this way. Instead, the specificity for a product is distributed between the original coding sequence, cis- regulatory sequences and trans-acting factors that bind to those regulatory sequences and to one another. In earlier work my collaborators and I have proposed an information-theoretic measure of specificity. I apply this measure to the sources of the ‘distributed specificity’ for a gene product. This work gives a precise meaning to Francis Crick’s insight that coding sequence contain the ‘information’ that specifies their products, reveals that information in precisely the same sense can be found in gene regulatory mechanisms, and lets us trace some of the information contributed by those mechanisms back to its sources in environmental drivers of gene expression.