by Mark Brown
http://www.wired.com/wiredscience/2011/10/vertebrate-lineage/
Just about every vertebrate on Earth descended from an ancient ancestor with a sixth sense. the sixth sense being the ability to detect electrical fields in water. Evolutionary biologists from Cornell University have found that over time lobe-finned fishes still have electrorception. Birds and mammals have lost their electrosense and the lateral line. Sounds like it would've came in handy, if we still had it.