After more than two years of hiatus to recover from an injury, a rare two-headed snake is back on exhibit at a zoo in Texas, taking the spotlight once again.
The extraordinary snake has two names, one for each head: Pancho and Lefty. It’s now dwelling within a specially designed enclosure at the Cameron Park Zoo in Waco, located in Central Texas between Dallas and Austin.
Pancho and Lefty first arrived at the zoo back in 2016. A woman who lives near Waco spotted the snake in her backyard when it was just a baby—at the time, biologists estimated the eight-inch-long creature to be between six and eight weeks old. The reptile, a Western rat snake (Pantherophis obsoletus), underwent an 18-month quarantine before going on display in 2018.
The snake has a rare condition called bicephaly, which occurs when a single embryo starts to divide into identical twins but fails to separate completely. When this situation arises in humans, it’s known as conjoined twins. Scientists can trace the phenomenon back at least 150 million years, thanks to the discovery of a two-headed reptile fossil in present-day China.
But trying to navigate the world with two heads—and, thus, two brains—is challenging. Because Pancho and Lefty’s body is receiving signals from two command centers, its movements are uncoordinated and awkward. And in February 2021, the snake injured its left neck while trying to move in two different directions at once. Zookeepers removed the snake from public view to give it time to recover.
The wound took more than a year to heal, then veterinarians decided to give the animal an additional year off exhibit to get back to full health.
Now, the snake’s exhibit, located in the zoo’s freshwater aquarium building, does not contain any rocks or branches that its necks could get caught on—just grass. “We are hoping that this design provides enough cover for the snake to feel secure while also being physically safe, so he does not injure his neck again,” the zoo wrote on Facebook.
The snake is now 8 years old and measures two to three feet long, per the Dallas Morning News’ Sarah Bahari. That’s a little on the small side for a rat snake, which typically grow to between three and five feet long, per the University of Georgia’s Savannah River Ecology Laboratory.
When Pancho and Lefty first arrived at the zoo, its left head was the more dominant side and usually consumed most of the creature’s meals, the Waco Tribune-Herald’s Kristin Hoppa reported in 2018. Now, however, the right brain appears to have taken over.
“The right brain is much more dominant and tends to control where they go,” says Maddie Michels-Boyce, senior zookeeper for reptiles and amphibians, to the Dallas Morning News. “The left brain is seemingly just along for the ride.”
Snakes—and other creatures—born with two heads often fail to survive in the wild, as having two brains means the body gets conflicting messages, and sometimes in crucial moments—such as when deciding which direction to flee from a predator. Case in point: In 2020, a family in Florida discovered a two-headed southern black racer snake after their cat dragged the creature into the house through the doggy door.
For snakes, it seems, two heads may not always be better than one.