anthropologist joao zilhao believes the evidence offers a glimpse into the neanderthal mind. now, he is reexamining finds from a neanderthal site in spain excavated in the '80s. zilhao: this is a fragment of a naturally pointed horse bone and when we looked at the tip of the bone under the microscope we found that there was lots of reddish dots. narrator: although so faded they are hard to see the chemical analysis proves the spots are the red pigment hematite. and there is more. zilhao: this shell is from the mediterranean oyster and you can see adhering to the inner side of the shell a remnant of a pigment which is black and reflective. narrator: zilhao has found a pencil-like sliver of bone with a red mineral at its tip, and a shell stained with a shiny pigment alongside other fragments of colored minerals. it adds up to a significant collection, or so zilhao believes. you know, they look like just shells collected off the beach but the amount of information they contain is tremendous. narrator: putting all the pieces of the puzzle together zilhao is convinced he is looking