Defining function under ENCODEs 80% marker In biology, there are two main concepts of function: the selected effect and causal role concepts of function. The selected effect concept is historical and evolutionary (Millikan 1989; Neander 1991). Accordingly, for a trait, T, to have a proper biological function, F, it is necessary and (almost) sufficient that the following two conditions hold: 1) T originated as a reproduction (a copy or a copy of a copy) of some prior trait that performed F (or some function similar to F) in the past, and 2) T exists because of F (Millikan 1989). In other words, the selected effect function of a trait is the effect for which it was selected, or by which it is maintained. In contrast, the causal role concept is ahistorical and nonevolutionary (Cummins 1975; Amundson and Lauder 1994). That is, for a trait, Q, to have a causal role function, G, it is necessary and sufficient that Q performs G. The ENCODE argument goes like this: 1) DNA segments that function in a particular biological process (e.g., regulating transcription) tend to display a certain property (e.g., transcription factors bind to them). 2) A DNA segment displays the same property. 3) Therefore, the DNA segment is functional. Notice that ENCODE have not delivered a distinct classification here, however, it is clear of which definition, function, is relating. Or is it? At first glance, you would be drawn towards the selected effect definition because such function as noted in example (transcription regulation) suggest this is a reproduced process that has been handed down from parent to offspring. And indeed, this is surely the case, However, it has long been understood that the regulation of transcription is a driving force behind complexity (Sacha A. F. T. van Hijum. Marnix H. Medema and Oscar P. Kuipers - Mechanisms and Evolution of Control Logic in Prokaryotic Transcriptional Regulation) The definition for function as used by ENCODE fits with both selected effect and causal role the correct definition used for function according to (Millikan 1989; Neander 1991) and (Cummins 1975; Amundson and Lauder 1994). Meaning the 80% margin provided suits both evolutionary concepts of inheritance but also the concept of specified complexity ( William A. Dembski - The Design Inference: Eliminating Chance through Small Probabilities (1998) What about chance? Well, what about it? Whenever explaining an event, we must choose from three competing modes of explanation. These are regularity, chance, and design... To attribute an event to design is to say that it cannot reasonably be referred to either regularity or chance. ― William A. Dembski, (The Design Inference: Eliminating Chance Through Small Probabilities) And so it comes down to the definition used to explain biochemical activity. ENCODE used both selected effect and causal role to explain of what is happening within that 80% of the genome. Both the selected effect and causal role both conform to design parallels as both prohibit Darwinian random evolutionary interjections, as both infer strict regularity and performance as would be expected behind a designed system. https://youtube/watch?v=_bjKH43pRB0
Posted on: Wed, 24 Dec 2014 19:36:41 +0000
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