Sal explains to Rebekah why most mutations are not good by taking the illustration of the potassium Ion Channel. "not good" means functionally damaging or of no functional effect at best.
Ion channels illustrate the absurdity of evolution by slow incremental steps for the evolution of major protein families that require many parts to exist at the same time.
This is an UNEDITED version (63 minutes) of the edited version (30 minutes) that was aired on the Examining Evolution channel hosted by Rebekah Davis that can be found here:
Many thanks to Rebekah Davis for helping make this video possible.
[
ERRATA: This is Sal. The difference in sizes between plain vanilla K-channel and voltage-gated K-channel was a mistake on my part. However compare the size of a K-channel polypeptide of about 500 residues to a Na-channel to about 2000, and there is a huge difference. That would be a better example than the mistaken one I gave. Apologies.
]
[Thumbnail is a Richardson Ribbon rendering of a voltage-gated potassium ion channel]
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