Several high-profile monkey stories have made headlines in recent years, from lab escapes to controversial brain-implant experiments. If you searched “what happened to the monkeys,” you’re likely looking for one of these events. Here’s what happened in each case.
The South Carolina Monkey Escape
In November 2024, 43 rhesus macaques escaped from the Alpha Genesis Primate Research Center in Yemassee, South Carolina, after a new employee left an enclosure door open. The breakout made national news as residents wondered whether wild monkeys posed a safety risk in their neighborhoods.
Within days, 39 of the 43 monkeys were recaptured. Recovery teams used food lures, including peanut butter and jelly sandwiches and monkey biscuits, to coax the animals back. Veterinarians conducted wellness exams on every recovered primate and reported they were all in excellent health. Police emphasized there was no public health threat, and search efforts continued around the clock for the remaining four.
Neuralink’s Primate Deaths
Elon Musk’s brain-computer interface company, Neuralink, faced intense scrutiny after veterinary records revealed that as many as 12 monkeys used in implant experiments had to be euthanized following severe complications. The documents, originally obtained through a California public records request, described bloody diarrhea, partial paralysis, and brain swelling among the test subjects.
One case involved a monkey identified as “Animal 20.” During a December 2019 surgery designed to test whether an implant was survivable, part of the device broke off during the procedure. Overnight, the monkey scratched at the surgical site, which oozed bloody discharge, and pulled at a connector until it partially dislodged the implant. A follow-up surgery was performed the next day, but fungal and bacterial infections set in. The monkey was euthanized on January 6, 2020.
Perhaps the most disturbing account involved a female monkey called “Animal 15.” Days after her implant surgery, she began pressing her head against the floor, a sign of pain or infection. Staff watched her pick and pull at the implant until it bled. Despite her deteriorating condition, she would lie at the foot of her cage holding hands with her cagemate. Over the following months, she lost coordination and began shaking uncontrollably whenever she saw lab workers. After months of decline, staff euthanized her. A post-mortem examination found bleeding in her brain and portions of her cerebral cortex described as “focally tattered.” Another monkey, Animal 22, was euthanized in March 2020 after a cranial implant came loose.
The Pennsylvania Highway Crash
In January 2022, a truck carrying 100 lab monkeys crashed on a highway in Pennsylvania after colliding with a dump truck. Several cynomolgus macaques escaped from damaged crates at the scene. A bystander who approached the wreckage spoke to the pickup driver, who appeared disoriented, before realizing the cargo was live primates.
By the following day, the CDC confirmed all 100 monkeys had been accounted for. Three were euthanized, though officials did not explain why. The CDC said the euthanasia was carried out humanely following American Veterinary Medical Association guidelines. The truck drivers were not seriously harmed, and a passenger was taken to a medical center for suspected minor injuries.
Florida’s Wild Monkey Colonies
Florida has maintained a free-roaming population of rhesus macaques for decades, centered around Silver Springs State Park. These monkeys are descendants of a small group released near the Silver River, likely by a tour boat operator in the 1930s. By 2015, the population had grown to roughly 175 animals across five groups, and a 2018 study found at least 134 macaques spread across a 20-mile stretch along the Ocklawaha River.
Between 1984 and 2012, the state attempted to control the population by trapping and removing monkeys. About 1,000 were captured and sold to biomedical research facilities during that period. The practice was deeply controversial and eventually stopped. Today, feeding wild monkeys in Florida is illegal. The Florida Fish and Wildlife Conservation Commission defines “feeding” broadly to include placing food or garbage in any way that attracts them. The current population size is unknown.
One concern with wild macaques is B virus, a herpes virus that most captive macaques carry by the time they reach adulthood. Human infection is extremely rare, and most people will never come close enough to a macaque for transmission to be a realistic risk. Still, the CDC advises against approaching or feeding wild monkeys.
The Bigger Picture for Primates
Beyond these individual news events, primates as a group are in serious trouble worldwide. Nearly two-thirds of all known primate species and subspecies, 464 out of 720, are now classified as threatened on the IUCN Red List. Of those, 312 are Endangered or Critically Endangered. Habitat loss, hunting, and live capture are the primary drivers. The scale of decline means that many primate species could disappear within a generation without significant conservation intervention.