What's the Kennection? #58

Welcome to Kennections, a weekly quiz created by Jeopardy! champion/co-host Ken Jennings. Here's how to play: All five answers to the questions below have something in common. Can you figure it out? (Note: We've given you a hint by showing you how many letters are contained within the answer, but this quiz is not interactive.)

1.  Philosopher Thomas Hobbes was the first to write about a final piece of what substance breaking a horse’s back?

— — — — —

2.  Roger Zelazny wrote ten “Chronicles” about what fantasy world ruled by nine princes?  

— — — — —

3.  Back when it was a British colony, the African nation of Ghana was named for what valuable export?

— — — —

4.  What fruit was the original garnish for a martini, before green olives became more common?

— — — — —

5.  What bird is named for the southernmost islands in Spain, where it originates?

— — — — — —

ANSWERS ----->