Final answer:
The harmony in the chorus of 'Big Yellow Taxi' features a mix of major and minor chords, creating a bittersweet harmony that accentuates the song's message about environmental and social loss.
Step-by-step explanation:
The harmony in the chorus of Big Yellow Taxi by Joni Mitchell is characterized by a simple yet playful structure that underscores the song's environmental and social message. The song's chorus features a combination of major and minor chords creating a bittersweet sonic texture that mirrors the lyrical juxtaposition of loss and nostalgia. The harmony is typically bright and catchy, which reinforces the sing-along quality while simultaneously carrying an undertone of poignant commentary on modern progress and its ecological cost. The effective use of harmony in both creating memorability and enhancing the song's themes is a testament to Mitchell's skill as a songwriter.