It's funny you should ask that. We use the Orchard. Testing the Orchard Model and the NCSE's Claims of "Nested Patterns" Supporting a "Tree of Life" - Evolution News & Views
Use it for what, specifically? What research are creationists doing based on this model?
Michael Behe's Blog - Uncommon Descent - Part 2
In the paper Bridgham et al (2009) continue their earlier work on steroid hormone receptor evolution. Previously they had constructed in the laboratory a protein which they inferred to be the ancestral sequence of two modern hormone receptors abbreviated GR and MR (Bridgham et al 2006). They then showed that if they changed two amino acid residues in the inferred ancestral receptor protein into ones which occur in GR, they could change its binding specificity somewhat in the direction of modern GRs specificity. (All the work was done on molecules in the laboratory. No measurements were made of the selective value of the changes in real organisms in nature. Thus any relevance to actual biology is speculative.) They surmised that a gene duplication plus sequence diversification could have given rise to MR and GR. As I wrote in a comment at the time ( CSC - Michael Behe On The Theory of Irreducible Complexity ), that was interesting work, and the conclusion was reasonable, but the result was exceedingly modest and well within the boundaries that an intelligent design proponent like myself would ascribe to Darwinian processes. After all, the starting point was a protein which binds several steroid hormones, and the ending point was a slightly different protein that binds the same steroid hormones with slightly different strengths. How hard could that be?
Well, it turns out that Darwinian evolution can have a lot of trouble accomplishing even that simple task, or at least its opposite. In the new paper the authors try the reverse experiment. They begin with the more modern hormone receptor (which is more restrictive in the steroids it binds) and ask whether a Darwinian process could get the ancestral activity back (which is more permissive). Their answer is no, it couldnt. They show that a handful of amino acid residues in the more recent receptor would first have to be changed before it could act as the ancestral form is supposed to have done, and that is very unlikely to occur. In other words, the new starting point is also a protein which binds a steroid hormone, and the new desired ending point is also a slightly different protein that binds steroid hormones. How hard could that be? But it turns out that Darwinian processes cant reach it, because several amino acids would have to be altered before the target activity kicked in.
So what research are IDers doing to show how this steroid receptor really came about?
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