Who were the people of ancient India that collected trash and skinned animals?

The people who collected trash and skinned animals were the Pariahs. They were also known as the untouchables or dalit. They skinned animals and handled dead bodies. When the Pariahs traveled they tapped two sticks together so the people in higher castes could hear them coming and have time to move away. Most ancient Indians believed that being near the Dalit was harmful so they were forced to live apart from other ancient Indians. The Dalit lived very dirty lives and didn't belong to a varna.