William Aird/X
Jul 26, 2025, 18:32
From Jawless Fish to Mammals: Clotting Cascade Origins
Dr. William Aird, Professor of Medicine at Harvard Medical School, has posted on X:
“Origins of the Clotting Cascade: Divine Intervention or Natural Selection?
Ok, ok it is a rhetorical question, but an entertaining one, nonetheless.
Some creationists argue that the clotting cascade is irreducibly complex, too intricate to have evolved step by step.”

This phylogenetic progression illustrates that what some deem “irreducibly complex” actually arose through incremental protein additions—each conferring a selective advantage in controlling bleeding and maintaining vascular integrity.
Find more on Hemostasis Today.
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