In November of 1621, so the story goes, the Wapanoags shared a harvest feast with the English colonists of the Plymouth Plantation in what is now the state of Massachusetts.  That event, now etched in our collective minds as the first Thanksgiving, has come under increased scrutiny in recent years.  Was that a peaceful sharing of bounty and gratitude, or the prelude to displacement, territorial landgrabs, and the destruction of an indigenous culture?  As a result of the expansion of European settlement, many indigenous traditions, including the very agriculture that produced much of the food eaten at that first Thanksgiving, have vanished.  Christina Gish Hill is an anthropologist at Iowa State University, and she is part of a team of researchers that are trying to restore traditional Native American agriculture to the people who once practiced it.