The regal African elephant (Loxodonta africana) stands 12 feet tall, weighs upwards of 10,000 pounds, and can live up to 70 years. Its trunk, a wonder of nature, has tens of thousands of muscles. And the social behavior of these animals, especially their family dynamics, is as complicated, subtle, nuanced and as spectacular as any species. People have been fascinated with African and Asian elephants (Elephas maximus) for thousands of years, but we are only just beginning to understand them. And, once in a blue moon, a series of events occurs that sheds light not only elephants themselves, not only on fundamental questions about behavior. One such series of events took place in the Pilanesberg National Reserve in South Africa in the late 1990s.

Source: AndreKlopperShutterstock

In a nutshell, what happened was this: the beautiful and endangered white rhinos there were being killed and no one knew who the killers were. More and more white rhino bodies were turning up and still no answers. Poachers are a constant threat in that area, and the horns of white rhinos are sadly one of their major targets. But the horns were still on the bodies of the rhinos and there was no evidence that poachers were involved.

Slowly, by gathering information at the site of the kills, and more importantly, by collecting meticulous notes on the day-by-day behavior of the animals at Pilanesberg and looking at the data he had gathered during the period prior to the killings, Gus van Dyk, a zoologist at Pilanesberg, became Gus van Dyk the detective, and pieced together what had happened. To his utter shock, the evidence pointed to the killers being elephants. This was virtually unheard of, anywhere. Elephants and rhinos certainly interact with one another in the wild, but it never ends in one of them killing the other—never. But here it had, and many times over many years. Understanding why, van Dyk realized, was just as important, perhaps more important, than fingering the culprits.

Over time, using day-to-day behavioral charts he had compiled on each and every elephant at Pilanesberg, along with a detailed understanding of the science of , van Dyk solved the “why” mystery as well. Not all the elephants at Pilanesberg were guilty. Indeed the killings could be traced to…well, for lack of a better term, a group of male juvenile delinquent elephants. What had happened was this: back in the mid 1980s, a decade before the killings, the number of elephants at Kruger Park—another nature reserve in South Africa—was growing too quickly. The staff at Kruger decided to send about 20 very young elephants, 5- to 8-year-olds, to Pilanesberg to reduce the population there at Kruger. At the time, it was not possible to move adult elephants that distance so only the youngsters, both male and female, were shipped to Pilanesberg.

Ten-plus years had now passed and those young (transplanted) elephants had grown into , in the range of 15 to 18 years of age. About half of them were males. For years, they had roamed around together with no supervision from older males, for there were no male elders to supervise them and keep them under control. Normally male elephants do not go into what is known as musth, becoming reproductively active, secreting huge amounts of ( levels can increase 6,000 percent over pre-musth periods) and searching for mates, until they are in their mid-20s, but the transplanted teenager males were already in musth. Without adult males to keep them in check through the normal behavioral interactions between teenage males and adult males, the fatherless, adult-male-less teens had matured too quickly. The hormone surge of testosterone associated with musth was, apparently, too much to handle at 15 to 18 years of age. This had spilled over into highly aggressive behavior by these teenage males. And that was vented, in part, on their unfortunate white rhino victims.

Van Dyk, in a massive undertaking, arranged to have adult males brought into the Pilanesberg reserve (the technology was available for that by the late 1990s, unlike when the young elephants were first brought to Pilanesberg) and observed the behavioral interactions between these new adult males and the teenage troublemakers. Quickly, the new adults established themselves as dominant to the teenagers. The juveniles went out of musth. Not a single white rhino was harmed after that. Not one.