Oysters have been around for approximately 15 million years. An oyster becomes an adult when it turns one year old and can live as long as 20 years. Oysters can change their sex. In fact, they will often do it more than once. Scientists exploring a cave in South Africa report evidence of shellfish dinners enjoyed by humans who lived 164,000 years ago. Anthropologists say the find could point to one of the earliest examples of modern behavior.
Oysters are high in zinc. While this mineral is important for health, consuming too much can be harmful. Though zinc toxicity is most often associated with supplements, eating too many oysters too frequently can lead to negative health effects, such as reduced levels of the minerals copper and iron that zinc competes with for absorption.