Rare two-headed snake is surprisingly thriving

When two employees at the East Bay Vivarium in Berkeley, California, pulled a baby snake from the incubator seven months ago, they must have thought they were seeing double. The hatchling was a California kingsnake (Lampropeltis californiae), a white non-venomous snake with black splotches—and two heads. 

The snake is an example of conjoined twins, when two babies are born fused together, sharing a varying degree of organs. In this case, the snake appears  to have one set of functioning organs with a second head that’s “kind of along for the ride,” Johnathan Emberton, owner of the East Bay Vivarium, tells Popular Science. While the extra head is definitely sentient—it breathes, looks around, flicks its tongue, and apparently gets mad if you poke it—it doesn’t eat.

“The dominant head is the only one that’s eaten,” he explains. “The other one shows a little interest [in the food], but really hasn’t even tried to eat.” The team at the vivarium theorizes that the non-dominant head doesn’t control any of the organs, and that its esophagus ends where the two bodies meet. 

While the birth of conjoined twins is unusual, it’s not unheard of. In the past 35 years, the East Bay Vivarium has seen other snakes, as well as tortoises, turtles, and geckos, hatch with two heads. What’s rare about this particular snake is that at seven months old, it’s already lived significantly longer than all the other sets of conjoined twins. 

“It’s very rare that you hatch one at all, and then it’s extremely rare when they live,” Emberton says. With conjoined twins, “you might have two sets of hearts and two sets of lungs and two sets of stomachs, which all are either competing against one another or one needs to support the other.” For this reason, the snake is lucky to have been born with just one main male body. “If it had two sets of functioning organs, we probably wouldn’t be talking today. And it would probably be in an alcohol jar.” 

In fact, the vivarium’s staff only told the world about their special snake back in March, when it had turned six months old. Once the snake reaches its first birthday later this year, the team will start thinking about its potential next home. 

According to Emberton, the snake doesn’t miss a meal and, surprisingly, doesn’t have too many issues shedding. The team calls it Zeke and Angel, in honor of the employees who pulled it out of the incubator, but there is an “an ongoing contention about who’s who,” Emberton laughs. “You’ll have to argue with those two.” 

 

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