The world’s oldest known figurative artwork to date has been discovered in a cave in Indonesia: an image of a reddish, warty pig.
Painted using red ochre pigment, the animal appears to be watching a fight between two other warty pigs.
Explorers were confident the image, which is in profile and filled in with irregular patterns of painted lines, was of a warty pig, because of its spiky head crests and facial warts.
In a study published on Wednesday in the journal Science Advances, archaeologists working at the site on the island of Sulawesi calculated the drawing was at least 45,500 years old.
It is thought to be the oldest surviving image of an animal and sheds new light on the early story of humanity.
Previously, the oldest known cave art was of abstract symbols thought to have first appeared in Europe 40,000 years ago but these Indonesian discoveries challenge that.
Rock art made in limestone caves can sometimes be dated by measuring the radioactive decay of elements like uranium within calcium carbonate deposits, sometime called cave popcorn, that form naturally on the cave surface.
Analysis of a small cave popcorn found on the rear foot of the pig indicates it was painted before 45,500 years ago and could actually be much older.
That makes this warty pig more ancient than other types of prehistoric art found in Europe such as the “Lion-man”, a figurine of a lion-headed human, and a “Venus figurine” carved from mammoth ivory, both found in Germany and thought to be around 40,000 years old.
It’s also more ancient than a recent find on another Southeast Asian island: an image of cattle found in a cave in Borneo.
The team expects future research in eastern Indonesia will lead to the discovery of much older rock art and other archaeological evidence, dating back at least 65,000 years.
Study author and Indonesian rock art expert Adhi Agus Oktaviana said, “We have found and documented many rock art images in Sulawesi that still await scientific dating. We expect the early rock art of this island to yield even more significant discoveries.”
Warty pigs are still common in Indonesia and the descendants of the one in the cave have long since been domesticated.