Thanks to archeology, we know amazing details of the human past, but there is one aspect of this ancient and accredited discipline that is still in the shadows: the study of the animal past through stone tools and other objects that bear its imprint.
The main difficulty is that the materials used by animals to modify their environment , such as leaves, sticks and twigs, are perishable, they disappear without leaving a trace . An exception is the crab-eating macaque ( Macaca fascicularis ), an Asian ape that uses hard and durable stone tools to open shells, crab shells, and nuts.
As reported in the Journal of Human Evolution , a group of experts from the University of Oxford, led by Michael Haslam, have chosen this species to carry out pioneering work in “simian archeology” on the Thai island of Piak Niam Yai . And the excavations have borne fruit: ten stone tools that were unequivocally manufactured by crab-eating macaques 65 years ago . The dating has been carried out by calculating the age of the shells –organic remnants– that were found in the same strip of sediments.
The human inhabitants of the area already knew that the monkeys used these tools at least 120 years ago, but scientists are confident that, by going deeper into the site, they will find older pieces and will be able to discern when and how this ability arose among the apes . Chimpanzees, for example, are believed to have been doing this for 4,000 years. “We are in the year zero of primate archeology,” Haslam announced.
Photo: crab macaque. Credit: Midori / Wikipedia
