Misc: What does an ichthyologist study?

Questions

any of a group of composite organisms made up of a fungus and an alga living in symbiotic association (symbiosis)?

what race's runners refer to the noisy section along wellesley college as the 'screech tunnel'?

alcoholic beverage produced by fermenting the juice of grapes?

who recorded 'you're so vain'?

who played victoria barkley on the tv show, 'the big valley'?