A team of conservationists monitoring sea turtle hatchlings in South Carolina recently stumbled upon a rare oddity. They were assessing the contents of a loggerhead turtle nest when, to their surprise, they found a little hatchling with two heads. They charmingly named the critter Squirt and Crush after Nemo’s reptilian pals.
Sea Turtle Patrol works to protect turtles on Hilton Head Island but aims to keep everything natural for the animals. Therefore, they did not collect the bicephalic hatchling to rear in captivity and instead released it into the sea. The baby turtle was struggling to crawl due to its abnormally shaped shell and it’s unclear how well it will cope in the ocean as the survival rate of healthy hatchlings is low.
“Sea turtle patrol follows rules set by the State Department of Natural Resources which calls for us to protect the nests and turtles but to also allow as natural a process as possible,” the turtle’s discoverer, Jayme Davidson Lopko, wrote in a Facebook post. “We do not take hatchlings off the beach to raise or rehabilitate. This little guy is on his own just like his brothers and sisters that came from the nest and like they have been doing for millions of years.
“Good luck and safe travels special guy!”
While having two heads is extremely rare, it is a little more common in reptiles than other animals. In fact, Davidson Lopko notes that in her 15 years of monitoring nests she has found a couple of two-headed hatchlings (including Squirt and Crush). In addition to turtles, bicephaly has also been reported in lizards and snakes. Reptiles are more likely to be bicephalic because they produce a large number of offspring and because most reptiles lay eggs. These eggs are exposed to environmental conditions that might affect the development of the embryo inside.
Bicephaly can result from both genetic and environmental anomalies during an embryo’s development. Sometimes, an embryo splits in two (which is how identical twins form) but does so incompletely. This is what causes conjoined twins in humans although it is incredibly rare for them to have two heads. Meanwhile, sometimes two separate embryos can fuse together but only partially, resulting in the development of a two-headed animal.
It’s unclear what will happen to Squirt and Crush out in the Atlantic but we wish this real-life little mutant turtle luck as it journeys out into the sea. For more two-headed critters, check out the two-headed salamander tadpole of Israel, the bicephalic baby deer found in the US, and Brazil’s slightly creepy two-headed bat.