Last week, something strange arrived at the Cape Wildlife Center. Not one turtle, not two turtles—something in between. A tiny two-headed turtle weighing less than a nickel ended up at the Cape Cod facility.The bicephalic (two-headed) reptile is a diamondback terrapin (Malaclemys terrapin), aquatic turtles found in brackish waters along the United States’ Atlantic and Gulf coasts. Diamondback terrapins are classified as Threatened by the Massachusetts Endangered Species Act, and thei