---"This one had the beginnings of upper arm, forearm and wrist joints on it's pectoral fins. That's the significant difference.
Embedded in the fin of Tiktaalik are bones that compare to the upper arm, forearm and primitive parts of the hand of land-living animals.
"Most of the major joints of the fin are functional in this fish," Shubin said. "The shoulder, elbow and even parts of the wrist are already there and working in ways similar to the earliest land-living animals."---
Wow. This is a great find! Now we know how animals went from living on land to living in the seas! Their forearms, shoulders, and wrists eventually gave way to fins!
A great discovery!
By taking that one sentence out of context, I can see how one could arrive at this conclusion. But, the rest of the article makes it clear that, with this fish, at least, it happened the other way around.
Now, whales on the other hand, did adapt from living on land to living in the sea. (See: Living whales found with hindlimbs)