From Victoria Gill (BBC, 22 July 2011), we learn: “Mandrill monkey makes ‘pedicuring’ tool”:
Scientists from Durham University, UK, filmed the mandrill stripping a twig and using the resulting tool to clean under its toenails.
“A crude “pedicure” carried out by a mandrill at Chester Zoo suggests the monkeys are capable of more advanced tool use than previously thought.”
Good to know. But what about bird tool use? If (corvid) birds are better than monkeys, how should our views of evolution change?