Signers of the Dissent List have signed the list because it is their professional opinion that the evidence is lacking for the claims for the ability of random mutations and natural selection to account for the complexity of life. Period. Nothing more, and nothing less.
He then asks:
It's their professional opinion? Based on what, exactly?
What basis does Douglas Keil, who is listed as having a PhD in "Plasma Physics" have for forming a professional opinion on evolutionary biology? How about Jeanne Drisko, "Clinical Assistant Professor of Alternative Medicine" at the University of Kansas School of Medicine? Or Aaron Miller, who has a PhD in physics? Or mathematician Gary Dilts? Or "research meteorologist" John Brown? Or Baylor physical chemist John Burba? or Why on earth would I think that any of those people is in any way, shape, or form competent to form a professional opinion on a topic that falls outside their claimed area of professional expertise?
This is a persistent problem for creationists of all sorts. The grandfather of the recent creationism movement, Henry Morris, was a hydraulic engineer with no training whatever in biology.