- Sharks and humans share a distant relative that possessed a sixth sense.
- This shark-like relative of humans and sharks could detect electrical fields under water.
- The lineage that led to humans lost this ability a long time ago, but sharks and other fish retained the skill.
The common ancestor of sharks and humans -- and all jawed animals with a backbone for that matter -- possessed a sixth sense: the ability to detect electrical fields under water.
The anatomical tools for this ability, called electroreceptors and electrosensory ampullary organs, arose from the same cell population in both cartilaginous fishes (such as sharks and skates) and bony fishes (such as sturgeons and paddlefish) along with some salamanders, concludes the study, published in the journal Development.
Humans, even aquatic wonders like swimmer Michael Phelps, unfortunately lost this sixth sense a long time ago.
"There are absolutely no remnants of electrosensory ampullary organs in humans," lead author Andrew Gillis told Discovery News. "In fact, human embryos no longer possess the embryonic structures that give rise to the ampullary organs of our fishy ancestors. ... So we (meaning our overall ancestral line) have not possessed the ability to detect electric fields underw ater using ampullary organs for a very long time."