> But its taken from a fish not a block of wood?.<
Well, blocks of wood don’t have EPA.
Even statements like “derived from fish oil”, while correct in a literal sense, are misleading because the implication is that the magic is rooted in fish. It’s not.
Algae, a foundation of the fish food chain is the source of the PUFA’s found in fish oil. Fish is a concentrator for PUFA’s and commercial practices to collect, extract, and concentrate them from fish are the most economical at this time.
Possible future use of algae bioreactors has been discussed here.