Many aspects of their anatomy and physiology are actually very similar, said Dennis Scarnecchia, professor of fishery resources at the University of Idaho. Both species have scaleless skin, spiral valve intestines and cartilaginous endoskeletons.
Although it seems unlikely that two species would have so much in common after spending ages evolving independently, 184 million years isnt actually that long for these fish.
These living fossil fishes have extremely slow evolutionary rates, so what might seem like a long time to us isnt quite as long of a time to them, Dr. David said.
Although Dr. Mozsár and his colleagues plan to continue caring for the hybrids they created, they have no plans to make more. The researchers suspect that sturddlefish, like ligers, mules and so many other human-made hybrids, are sterile, so they have no value for caviar production. The creation of more sturddlefish could also imperil wild fish populations.
Nevertheless, the sturddlefish has captured the imaginations of scientists around the world.
I think its pretty cool that these living fossils can still surprise us, Dr. David said.