Countless musicians would love a lesson from Red Hot Chili Peppers bass supremo Flea, but Koko the gorilla became the RHCP man's surprise pupil as he visited the primate at the Gorilla Foundation in Woodside, California.
"This is just the greatest thing that could ever happen. This is the day that I will never forget in my life," Flea says in a video posted on the Red Hot Chili Peppers' YouTube.
In the clip, Flea watches on as Koko perfects a few strumming and muting techniques on Flea's new Fender Jazz Bass, while inspecting its Shell Pink finish and tweaking its control knobs.
"One of Koko's favourite musicians, Flea from the Red Hot Chili Peppers, came to visit," the Gorilla Foundation wrote on their website.
"Koko was thrilled by the mellow sounds and a jamming session followed with Koko strumming on Flea's bass!
"Watch for more news on future collaborations between the two."
Koko is famous for learning 1,000 signs and understanding around 2,000 spoken English words - expect 'slap', 'pop' and 'funk' to appear in her lexicon soon.
Flea was visiting Koko to raise funds for the Gorilla Foundation.