What is the rhythm of this Herbie Hancock song, and why is it so weird?

1. What was Herbie Hancock's biggest hit?
2. What style of jazz is Watermelon Man?
3. Why is watermelon man called Watermelon Man?

What was Herbie Hancock's biggest hit?

Hancock's best-known compositions include "Cantaloupe Island", "Watermelon Man", "Maiden Voyage" and "Chameleon", all of which are jazz standards. During the 1980s, he enjoyed a hit single with the electronic instrumental "Rockit", a collaboration with bassist/producer Bill Laswell.
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What style of jazz is Watermelon Man?

"Watermelon Man" is a jazz standard written by Herbie Hancock for his debut album, Takin' Off (1962). Hancock's first version was released as a grooving hard bop record, and featured improvisations by Freddie Hubbard and Dexter Gordon. A single reached the Top 100 of the pop chart.

Why is watermelon man called Watermelon Man?

The title of the song and its theme are based on the horsedrawn carts sold watermelons in Hancock's native Chicago. He says that the melodies are based on the sound of the horse hooves on the cobblestones and the ladies calling out, “Hey, watermelon man.”