Amino acids are the building blocks of proteins, and they can be used to learn about the diet and environment of ancient people. Scientists can extract amino acids from archaeological remains, such as shells, and use them to reconstruct the diet of the people who lived in that area at that time.

For example, a study of amino acids in shells from the Bronze Age in Denmark showed that the people who lived there ate a diet rich in fish and shellfish. This suggests that the people who lived in Denmark at that time were heavily reliant on the sea for food.

Another study of amino acids in shells from the Bronze Age in Greece showed that the people who lived there ate a diet rich in plants. This suggests that the people who lived in Greece at that time were more reliant on agriculture than on fishing and hunting.

The study of amino acids in shells can provide us with valuable information about the diet and environment of ancient people. This information can help us to understand how these people lived and how their diet and environment changed over time.