From “Lungfish Provides Insight to Life On Land: ‘Humans Are Just Modified Fish’” ScienceDaily (October 7, 2011), we learn:
“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.
Neat experiment, demonstrating the generally held position that bony fish are closer to tetrapods. But note the conclusion:
“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.”
Yeah, that explains mermaids.
We’re waiting for the paper that uses this data to show why guys are more likely to be attracted to mermaids than sharks.