In 1979, Alien came out and Sigourney was in it with a bunch a guys. Nobody at that time expected the woman to be the hero, so that was a tradition that started.
“My hat was pulled down and this girl said 'Are you really him?' I whispered 'Yeah, I'm really him.' She screamed, 'Mom! Dad! It's Heath Ledger!”
“I've always wondered what it would be like if somebody from outer space landed with three heads. Then all of a sudden everybody else wouldn't look so bad, huh? Well, OK you're a little different from me but, hey, ya got one head.”