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Geez, talk about seeing the glass half empty. Demonstrate evolution of multicellularity in a test tube and it gets nitpicked.

The cell clusters also were 10% less fit (that's quite an amount) than the beginning cells in the absence of the sedimentation selection.

And the cell clusters were 34% more fit (that's a bigger amount) than the beginning cells in the presence of the sedimentation selection.

What Behe needs to understand is that this is how selection works. One expects that the selected phenotype will have higher fitness in the new environment than in the old. There is no expectation for the selected phenotype to retain its fitness level for the old environment. For example, an animal moves from the tropics to the arctic. It adapts overtime by increasing fur, expanding fat layer, and losing sweat glands. It now has higher fitness in the arctic, but has reduced fitness in the tropics.

…the results can be regarded as the loss of two pre-existing abilities: 1) the loss of the ability to separate from the mother cell during cell division; and 2) the loss of control of apoptosis.

This glosses over a lot of stuff. The cell clusters were found to show size regulation. They grew to a certain size, but no larger. That max size could be adjusted by altering the sedimentation selection. So the cells aren't just dividing randomly and forming larger and larger clusters. There is a higher level of regulation going on here that you and Behe either ignore or don't understand.

Now consider this, though all the cells were capable of reproduction, the cluster reproduced only after it reached a minimum size. It appears that these clusters have a juvenile phase when they behave as if reproductively immature. Again, a higher level of regulatory complexity not seen in the individual cells.

As for apoptosis, much seems to have escaped Behe's attention (that's a shocker). First, there was evidence of size regulation of apoptosis, larger clusters correlated with higher rates of apoptosis. Experiments were done to show that largeness does not cause higher apoptosis, rather the conditions that selected for large size also selected for higher apoptosis rate. The two co-evolved.

Now what is interesting about that is that in the large clusters, only a small subset of cells undergo apoptosis. This causes a large cluster to break up into smaller clusters, essentially a form of propagation that increases the reproductive population. So somehow, in the larger cluster there is a division of labor, with some cells reproducing and others undergoing programmed death. The result is a cell cluster that has adapted itself to a new environment, even though individual cells may actually have become less fit. Such altruism!

This would be just one more example of evolution by loss of pre-existing systems

Not quite. The pre-existing systems aren't lost. They have been modified such that they now generate increased complexity and new functionality. One now has multicellularity, juvenile/adult development, size-regulated growth and reproduction, and within-cluster division of labor.

I didn't and don't plan to read your Behe link (life is too short for the same old same old). But if your excerpts accurately summarize his critique then he is either a fool or dishonest (again a shocker).

The apparently insurmountable problem for Darwinism is to build new systems.

It only seems that way. The actual problem is an inability of IDists to objectively read and understand the science they are criticizing.
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