Introducing.... Themes

As usual, no Google and post the answers in the comments.

1. What Black Sabbath hit shares its name with a comic-book hero?
2. The element Fe gives what bodily fluid its characteristic red color?
3. What is the Rh factor (also known as positive or negative) in blood named after?
4. What is the primary, and most obvious, anatomical difference between monkeys and apes?
5. Name one of the two writers who popularized the idea of “The Long Tail”.
6. In Jewish mythology, what is the name for a mindless automaton made out of clay?

The answers to last week’s:

1. Who was the first openly gay person to host the Oscars? Ellen DeGeneres.
2. What is the connection between Moby Dick (the whale) and Moby (the DJ and musician)? Moby, the musician, was born Richard Melville Hall; Richard Herman Melville, who wrote Moby-Dick, is Moby’s great-grand-uncle.
3. Who was the song “Hey Jude” written for? Julian Lennon, John Lennon’s first son.
4. Where was the first meeting of the United Nations held? San Francisco.
5. Why was the invention of movable type abandoned in its country of origin? Movable type was invented in China in the 10th or 11th century. It never caught on and was eventually abandoned because the vast number of Chinese characters made using type impractical.
6. Where is the Encyclopaedia Britannica headquartered? Chicago, Illinois. Though it has Scottish origins, the encyclopedia has been published in the United States since 1901.