It's not often you find a small pebble that can change our understanding of history and ourselves as a species. Yet according to an article published in the August 2019 edition of the Journal of Archaeological Sciences, a small oblong pebble—roughly palm sized in length— was found near Rome that "could have significant implications for the reconstruction of the cognitive and mathematical ability of Homo sapiens in prehistoric times."
According to the article, this small pebble is actually the oldest lunar calendar ever found. The pebble has small engravings that researchers say were made over a long period of time, with a variety of different cutting tools, and bear all the features of a lunar calendar. According to the article, the artifact may have been made around the end of the Pleistocene era, also known as the Paleolithic era in archaeology or the last ice age. According to a statement from the Sapienza University of Rome:
"It fits the definition of 'notational artifact' and is thus one of the very few known specimens of its kind in the world’s Paleolithic archaeological record. "
The pebble was found on Monte Alto in the Alban Hills south of Rome, Italy. It has three columns of engravings that researchers believe were used to store data. It was the particular arrangement and number of notches engraved in the stone that interested the researchers. The notches are cut perpendicularly along three edges of the pebble, in groups of seven, nine or ten (it's really old, give them a break), and eleven. The notches are symmetrically spaced and take up all available space. According to the study's author, Flavio Altamura of Sapienza University:
The study reveals that the notches were made over time using more than one kind of sharp cutting stone tool, as if they had been used for counting and calculating, or to store some kind of information over a period of time.”
That the number of engravings matches the exact number of days in a lunar month is evidence that it was a small, hand-held calendar.
However, the pebble seems to have been used for more functions than just a lunar calendar. The pebble was also used as a "retoucher-hammerstone", a tool to chip at and modify other stone tools. It was also used as a pestle to grind pigments including red ochre. Analysis of the stone shows that it was carved from limestone dozens of kilometers away from where it was found. This suggests that the stone was carried for quite some time before it was either lost or discarded on Monte Alto.
Things keep getting older, and this is just another example of how long we've been the species that we are. A small pebble that functions as a pigment pestle, hammer to make other tools, and a calendar, it's like a stone-age combination of a Swiss army knife and a smart phone, with more practical functionality than either.