Irreducible Complexity - Moving the Goalposts Again
Carl Zimmer summarizes some new research on the evolution of hormone receptors. For the specifics, just read Zimmer’s article (and his follow-up today)
But in general, the work shows how a so-called irreducibly complex system could have evolved. Hormone receptors are specifically matched to particular hormones. One without the other doesn’t do any good. This is the type of system that the ID’ers have trumpeted as irreducibly complex.
Yesterday, Michael Behe responded that:
a two-component hormone-receptor pair was too simple to be considered irreducibly complex. He said such a system would require at least three pieces and perform some specific function to fit his notion of irreducibly complex.
So, confronted with evidence that a hormone receptor system could have evolved, Behe argues that 2 components are not enough, 3 are required. Hormone receptors are not necessarily irreducibly complex.
Is that what ID’rs were saying last month? You gotta love Google.
from Was Darwin Right? -
Biological systems, from individual cells to whole ecosystems, abound with irreducible complexity. Below are some examples. …
Cells and receptors. Although the results are usually far more mundane than sex crazed wasps (see above), chemical signalling is essential for all biological processes. Living cells have numerous receptor molecules on their surfaces which are turned on and off by chemical signals sent out by other cells, or in the case of the wasp, another living organism. Quite often the interaction between one chemical signal and receptor is merely one step in a multi-step process that involves other types of physical and chemical reactions.
An effective signalling mechanism needs the signal, the receptor and the response mechanism to all to be present and functioning at the same time before it is functional. If any of these are missing the system is useless.
from Life’s Molecular Machines:
This is a hormone molecule. It is partially soluble in water and partially soluble in lipids, so it can slither through the membrane; that’s how hormones get into your body. Other molecules never even get into your body, but they send a signal through the membrane using a protein machine called a receptor. …
What you see here in pink is the receptor for this hormone. Every hormone has a receptor, and they go right together, just like coffee and cream. You can see that when that hormone binds to its receptor, the receptor takes good care of it, …
Just like the hormone and the hormone receptor bound like a lock and a key, so also these proteins bind together in order to fit into a particular three dimensional shape. …
First we’ll talk about some important definitions that will help us as we try to decide whether these machines are by chance or by design. …
Life requires molecular machines; life always has had molecular machines; therefore, I believe that life’s molecular machines originated by design.
I saved the screenshots. Maybe I’ll check back in next month.
She See Synapses in the Sea Sponges
Behe Disproves Irreducible Complexity
Moving the goalposts at the Weekly Standard
Intelligent Designation
Waiting for Confederate Yankee to Apologize