Limb Development and Our “Inner Fish”

Science Daily has a story on research delineating the relationship between us and fish.  The work, which examined some cartilaginous fish, as well as the three surviving lungfish species, was led by Peter Currie of the Australian Regenerative Medicine Institute at Monash University. The story notes:

"We examined the way the different fish species generated the muscles of their pelvic fins, which are the evolutionary forerunners of the hind limbs," said Professor Currie, a developmental biologist. Currie and his team genetically engineered the fish to trace the migration of precursor muscle cells in early developmental stages as the animal's body took shape. These cells in the engineered fish were made to emit a red or green light, allowing the team to track the development of specific muscle groups. They found that the bony fish had a different mechanism of pelvic fin muscle formation from that of the cartilaginous fish, a mechanism that was a stepping stone to the evolution of tetrapod physiology. "Humans are just modified fish," said Professor Currie. "The genome of fish is not vastly different from our own. We have shown that the mechanism of pelvic muscle formation in bony fish is transitional between that in sharks and in our tetrapod ancestors."

The paper is in the online journal PLoS and can be found here.  Another piece of the puzzle.  So...is it worse that we share common ancestry with chimpanzees or with fish?