R
rossum
Guest
Irreducibly complex systems can, and do, evolve. You are correct in that direct evolution of an IC system driven by natural selection is not possible but that does allow evolution of IC systems by indirect routes such as scaffolding or adaptation from another function. It also allows IC systems to arise by neutral mechanisms.I see the logic in irreducible complexity. This is where the rubber meets the road. There is no driver for adaptation when you see complex functions that can only work together but are independent.
For a complete, mutation by mutation, example of the evolution of an IC system see the Line of Descent from Lenski’s paper.
For the evolution of IC systems by a subset of available neutral mechanisms see Behe and Snoke’s paper (yes, that Behe). If even Behe thinks that IC systems can evolve then you might want to reconsider your position.
No, the functions may have existed for some other purpose. Your hands have many purposes, one of then can be to fan your face by moving air about on a hot day. Bats have taken this minor purpose - moving air - and turned their hands into a pair of wings for flight. Evolution can adapt mechanisms used for one purpose to serve a different purpose.The logical conclusion given the evolutionary model is that the functions must have always existed together.
Behe’s original statement was “IC cannot evolve”. This has now changed into “IC is unlikely to evolve” and the discussion has moved on to exactly how unlikely. If you are sticking to the old version then you are not in agreement with Behe himself who has, correctly, changed his position because of the evidence.
rossum