Neanderthals
SCIENTISTS RECENTLY DISCOVERED, FOR INSTANCE, A FOUR-WALLED STRUCTURE BUILT OUT OF ROCK BY NEANDERTHALS DEEP WITHIN A CAVE.
THE ABILITY TO CREATE SUCH A STRUCTURE, WHICH MAY HAVE HAD SYMBOLIC IMPORTANCE, IN THE PITCH BLACK CAVE REVEALS THE NEANDERTHALS HAD MASTERED THE ABILITY TO USE TORCHES AND TO COORDINATE THEIR ACTIVITIES, PERHAPS VERBALLY.