If high-tech gaydar equipment existed, you probably wouldn't need it. People can pick up on male sexual orientation based solely on how men pronounce the letters a, e, i, o, and u, reports US News. Researchers at Ohio State University conducted a study to see whether strangers could tell if males were gay or straight just by hearing them pronounce single-syllable words such as "food" and "sell." Participants got it right 75% of the time once they heard a vowel.
OSU asked seven homosexual and seven heterosexual males to speak for the experiment, and although respondents couldn't guess sexuality from the first consonant in words, vowels were a dead giveaway. "This is a phenomenon that occurs every day," says the study lead. "We are constantly speaking with people we don't know on our phones, and just from this conversation, we might be able to identify personal characteristics about that person, such as their gender, age, race, or sexual orientation."