Rare Two-Headed Baby Turtle Discovered on Cape Cod
The diamondback terrapin hatchling with bicephaly is being monitored at the Cape Wildlife Center.
A rare two-headed baby turtle, a diamondback terrapin hatchling, was found at a protected nesting site on Cape Cod in Massachusetts last month and is being cared for at the Cape Wildlife Center.
The hatchling exhibits bicephaly, a condition where an animal is born with two heads on a single body. This developmental anomaly is believed to stem from the incomplete splitting of a single embryo during the formation of identical twins. The tiny turtle weighs approximately the same as a nickel.
The Cape Wildlife Center, in conjunction with the Mass Audubon Wellfleet Bay Wildlife Sanctuary, is closely monitoring the hatchling's appetite, growth, and behavior. The center noted that encountering bicephalic cases is infrequent, with only two others observed in the past five years, deeming this particular case “especially rare.”
Zak Mertz, CEO of New England Wildlife Centers, stated that while such cases have been encountered before, each provides an opportunity to study the animals' anatomy and physiology. He explained that bicephaly is thought to be influenced by a combination of genetic and epigenetic factors. Potential contributing elements include the turtles' long lifespan, their tendency to return to specific nesting sites, and a limited gene pool due to their conservation status.
Environmental factors such as incubation temperature and humidity, nesting site characteristics, or parental exposure to certain elements could also play a role, Mertz added.
While rare, bicephaly has been observed in other species, including a two-headed porpoise and a two-headed dolphin. Studies on duplicated turtles indicate that they often exhibit significant abnormalities in their craniofacial structure and spine. These turtles typically are smaller than their counterparts and face survival challenges due to their unique anatomy.
Researchers believe that studying these rare instances offers valuable insights into the overall health of the diamondback terrapin species and its habitat. Diamondback terrapins inhabit brackish marshlands along the Atlantic and Gulf coasts of the U.S. and are classified as threatened under the Massachusetts Endangered Species Act.