McCartney wrote the song after seeing two monkeys copulating in the street while on retreat in Rishikesh, India with the Maharishi Mahesh Yogi. He marvelled in the simplicity of this natural scenario when compared to the emotional turmoil of human relationships. He later said:
''A male [monkey] just hopped on the back of this female and gave her one, as they say in the vernacular. Within two or three seconds he hopped off again and looked around as if to say, ‘It wasn't me,’ and she looked around as if there'd been some mild disturbance ... And I thought ... that's how simple the act of procreation is ... We have horrendous problems with it, and yet animals don't.''
Lennon was unhappy that McCartney recorded the song without him. In his 1980 interview with Playboy, he said:
Playboy: "Why Don't We Do It In The Road?"
Lennon: That's Paul. He even recorded it by himself in another room. That's how it was getting in those days. We came in and he'd made the whole record. Him drumming. Him playing the piano. Him singing. But he couldn't—he couldn't—maybe he couldn't make the break from the Beatles. I don't know what it was, you know. I enjoyed the track. Still, I can't speak for George, but I was always hurt when Paul would knock something off without involving us. But that's just the way it was then.
Playboy: You never just knocked off a track by yourself?
Lennon: That was mine Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.