Singer-songwriter David Bowie was a multi-talented, multi-faceted legend who served as a fashion icon, pushed musical boundaries and challenged ideas about gender. With a career that spanned more than five decades, Bowie's lasting legacy will endure for many years to come.

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Though Bowie was in the spotlight for most of his life, there are a few lesser known facts about him.

Here are seven things you might not have known:

1. He had anisocoria.

Bowie had anisocoria, or two eyes with unequally sized pupils. He developed the condition in his left eye after he and a friend got into a fight over a girl when they were 14. The altercation left him with a dilated pupil. He underwent two eye surgeries after the conflict, but his left pupil remained permanently open. Many people believe Bowie had two different colored eyes, but both of his eyes were blue. The enlarged pupil simply gave the effect of a different color.

2. He was born Robert David Jones.

Bowie changed his stage name to David Bowie in 1965 after failed attempts at success with the professional name Davy Jones. The switch was also fueled by an attempt to distinguish himself from Davy Jones of the American rock band The Monkees. It's said he chose the last name Bowie after the popularized knife.

"(It is) the ultimate American knife," Bowie said. "It is the medium for a conglomerate of statements and illusions."

Others said the last name was "sharp" and "cutting edge."

3. He had many alter egos.  

 The most popular of Bowie's alter egos was Ziggy Stardust, a glittery and flamboyant character that emerged in 1972. He was also known as Aladdin Sane and the Thin White Duke.

4. He released his last album on his birthday.

"Blackstar" was released on his 69th birthday, just two days before his death. The album includes seven songs and has been well received by critics. Producer Tony Visconti described the album as Bowie's "parting gift."

5. One of his most prized possession was a picture of Little Richard.

In 1998, Bowie told Vanity Fair his most prized possessions were, "a photograph held together by cellophane tape of Little Richard that (he) bought in 1958 and a pressed and dried chrysanthemum picked on (his) honeymoon in Kyoto."

6. He had a tattoo on his left calf.

The tattoo depicts a man riding a dolphin. A frog rests on the man's left hand. The tattoo also includes a Japanese translation of the serenity prayer.

"(It's) a confirmation of the love I feel for my wife and my knowledge of the power of life itself," Bowie said of the tattoo.

7. He died of liver cancer.

He had been diagnosed with the illness 18 months prior.

"Bowie was still writing on his deathbed," said Belgian theater director Ivo van Hove, who worked with the singer on the  Off-Broadway musical "Lazarus." "I saw a man fighting. He fought like a lion and kept working like a lion through it all."