Thrivin' From A Riff, recorded November 26, 1945, is an early version of what would become known as Anthropology, one of the defining rhythm changes contrafacts of the bebop era. Performed by Charlie Parker's Reboppers at a brisk 227 BPM in B-flat with a 32-bar AABA form based on I Got Rhythm changes, the track features Miles Davis opening with a one-chorus trumpet solo, followed by Parker's commanding two-chorus alto saxophone improvisation, and a one-chorus piano solo from Sadik Hakim. Parker's playing here is characteristically brilliant, with sweeping eighth-note lines that move through the chord changes with a fluency that set the standard for all who followed. Davis, still finding his voice alongside Parker, plays with a cautious but musical approach. This recording is part of the legendary November 1945 Savoy session and captures the tune before it acquired its more famous title. As one of the most frequently performed rhythm changes vehicles in jazz, the composition's significance to the bebop repertoire is difficult to overstate.