Though rumored for quite some time, scientists have officially reported the existence of maned female lions and have documented their more typically male behavior.
Geoffrey D. Gilfillan of the University of Sussex in Falmer, UK, and colleagues have observed maned five lionesses at the Moremi Game Reserve in Botswana’s Okavango delta. He and his teammates reported their findings in the African Journal of Ecology.
In males, long manes help attract females (they’re thought to indicate sexual health). Males also tend to mark their territory and roar more frequently. But this small set of Botswanan female lions took on some of these characteristically male behaviors—they even mounted other females. Gilfillan focused on one lion in particular, SaF05, which he’s been observing since 2014.
The team says that these lions’ manes are likely the result of high testosterone levels. Here’s Karl Gruber, reporting for New Scientist:
The idea that testosterone is implicated in the Botswana lionesses is also backed by observations of their reproductive success, says Kathleen Alexander at Virginia Tech in Blacksburg.
“While some of the maned lionesses were observed mating, none of them became pregnant, suggesting they are infertile, a known consequence of high levels of androgens such as testosterone in females,” she says. “The behavioural changes suggest this is likely the case.”
Hunter suspects this explanation applies to the animals studied by Gilfillan and his colleagues. “Given all five known maned females come from the Okavango region, there must be a genetic component in this population underlying the phenomenon,” he says.
Scientists have known for a few years that female lions in this region may carry a genetic disposition to this rare phenomenon, but this is the first time mane development in female lions has been formally documented.
Conservationists monitor such behavioral and biological changes to ensure that species will be able survive—but experts say that while none of these five females have become pregnant, they’re each fully capable of living healthy, long lives. The team doesn’t suspect the trend will become more common, but more research is needed to understand the exact hormonal and genetic factors that may cause these aberrations.
In male lions, mane growth is thought to be influenced by complex puzzle of genetics, temperature, nutritional status, hormones, and even vegetation thickness. As wildlife endocrinology becomes an increasingly important conservation tool, experts might look to cases like the Botswanan maned lioness to evaluate where species differ hormonally and how to minimize any negative effects of those variations on the general population’s well-being.