Hmm...Minnie and Pepper were afraid of all humans except me (although they were born indoors and reared as pets). Graybelle, the overgrown Manx who was mistaken for a bobcat, was afraid of heights. Mackerel, the only adult male cat I've kept, was not afraid of much--he chased a huge wild "coy-dog"--but he was afraid of vets (he was feral until he was three months old). Mackerel, his sister Polly, and his niece Mogwai seemed to *like* dogs, but his niece Grayzel was afraid of dogs. My current cats, his great- and great-grand-nieces? I only wish I could get them to be afraid, or at least healthily wary, of being stepped on. They're a team, and although each seems to have a specialized role, I've not noticed them being afraid of anything...not even vets!
And now I'll sign off for the night and go home and feed them.