ATLANTA—Concerned workers at the National Primate Research Center said Bobo, a 5-year-old chimpanzee participating in a 16-month cocaine study, was observed this week lying to the faces of friends, family, and staff.

"Our goal was to determine how large doses of the stimulant would improve or impair the chimpanzee's ability to perform memory and language tasks," said primatologist Daniel Martin, the project's lead researcher. "What we found was that cocaine not only disrupted Bobo's concentration and recall, but it also caused him to lie, cheat, and emotionally manipulate those around him."

Continued Martin, "Essentially, Bobo has become an asshole."

According to researchers, initial results of the study were promising, with Bobo energetically completing cognition tests in record times.

Within weeks, however, he reportedly began to develop violent mood swings, delusions of grandeur, and other troubling behaviors, such as begging his fellow participants to let him take their place in line so he could score a double dose of the drug he craved.

A researcher chronicles Bobo's descent into thievery and lies.

Witnesses said that once Bobo began taking advantage of the chimps in his life, family and friends further enabled his behavior by always giving him "one last chance."

"How many times can Bobo aggressively lash out at them, become contrite, act sorrowful, and then lash out again before they realize he has a problem?" research assistant Karen Grant said. "His life is spinning out of control, and they need to confront him about it. If they don't, one day they'll find him facedown under the tire swing—dead from an overdose."

By the third week of the study, Bobo had turned to theft to feed his growing habit: The addicted primate was observed stealing bananas from his loved ones, lying about it, and then attempting to conceal his misdeed by actually pretending to help them search for the missing fruit.

"Deceitful behaviors such as theft are highly unusual for primates," Martin said. "But the fact that Bobo approached us that same night and tried to exchange the stolen bananas for more cocaine is what's truly astonishing."

"It's like he's a different Bobo now," he added.

Early in the study, Bobo's elevated mood and excessive chattering made him quite popular among the other chimpanzees. But researchers claimed that his increased irritability, short temper, and absenteeism at the jungle gym did not go unnoticed.

According to laboratory sources, when Martin and his team began injecting Bobo with highly concentrated solutions of cocaine, the chimp took to skipping meals altogether, often covering up for his lack of appetite by signing to friends that he had eaten a big lunch that day and wasn't hungry.

Last February, Bobo reportedly grew so self-deluded that he believed he had become the group's alpha male. In reality, however, his rank in the dominance hierarchy had reached a new low, especially after several cocaine-fueled episodes in which he threatened other males and then made forceful, awkward advances toward uninterested females.

"It was embarrassing," Martin said. "A lot of our researchers have been unable to look at Bobo the same way since."

Chimp sources confirmed that in recent weeks Bobo has stopped hanging out with friends in the control group, who only receive a placebo.

"Fight. Mad. Bobo. Please more juice drink," Pipa, a 6-year-old chimpanzee, told reporters by pressing symbols on a specially designed keyboard. "Pipa scared. Old Bobo. We want back."

Claiming they don't even know who the chimpanzee is anymore, researchers hypothesized that the constant ingestion of cocaine may have taken a physical toll on Bobo, who now staggers around on all fours, grunts nonsensically, and has been spotted trying to groom insects that aren't actually there.

Martin acknowledged that Bobo's cognitive abilities have also suffered, saying that the restless primate no longer shows any interest in finishing his assigned tasks and often does little more than flip off the researchers.

"We definitely didn't teach him to do that," Martin said. "That's totally the cocaine."

As of press time, Bobo was reportedly sprawled out on the floor of the laboratory, begging for more cocaine and offering to give researchers hand jobs in exchange for some.