Almost everybody has heard or believes that oysters are an aphrodisiac, but nobody seems to know why. Wired looked back at the study done by Italian scientists who cracked open some mollusks and discovered an amino acid that, when given to lab rats, increased their testosterone and progesterone. Those higher hormone levels don’t necessarily mean the rats felt especially sexy, but the connection makes sense. Most interestingly though, it wasn’t oysters in which they found this amino acid, it was mussels. So on your next date, maybe skip the oysters and order moule frites instead.