A Japanese macaque monkey by the name of Yakei overthrew the alpha male in her troops and became the first female alpha in over 70 years on the reserve.

Yakei is 9 years old and leads a colony of 677 monkeys at Takasakiyama Natural Zoological Garden, which was established as a monkey sanctuary in 1952. 

The macaque is often known as the snow monkey and is highly intelligent.

The macaque way is governed by a rigid hierarchy. The higher a monkey's rank, the more access it has to food, mates, and resting places. 

Females inherit ranks behind their mothers and seldom leave the group into which they were born. When males reach puberty, they leave their natal troop and join a new group, where their rank is typically decided by the amount of time they have spent in the troop. However, status is often attained by acts of violence, usually amongst men. 

Yakei defied primatologists' expectations when she beat up her own mother to take first place among her troop's females. While most girls would be satisfied with it, Yakei continued to struggle.

She then assaulted three high-ranking males, then proceeded to overtake Nanchu, a 31-year-old macaque who led the troop for five years.

Mr. Kaigaishi, who studies the behavior of Japanese macaques, said, “She physically attacked and defeated Nanchu, consequently acquiring the highest ranking in the troop."

Reserve workers confirmed Yakei's alpha status when males and females of her troop stepped aside and she ate peanuts provided by workers first.

Kaigaishi described that since then, she has displayed behaviors only typically seen in dominant males, like walking with her tail up and shaking tree branches with her body. 

Although most alphas maintain their dominance for months to over a decade, the mating season may prove challenging for Yakei as the monkeys form paid bonds. 

Katherine Cronin of Lincoln Park Zoo in Chicago says mating season makes the environment in a macaque society more tense and competitive.

Previously, Yakei partnered with Goro, a 15-year-old male ranked sixth in the troop. In 2019, he bit her on the face and her bottom flushed bright red; a sign the reserve says demonstrated her willingness to accept him as a mate. Now that she is officially alpha, Goro appears to no longer be interested in her.

Since then, an 18-year-old Luffy, rated fifth in the troop, has had his attempts to impress Yakei rejected. According to one of the guides, “Luffy likes Yakei, but it appears one-sided."

Her reign may soon be over as Kaigaishi said that Yakei showed a "fear grimace", which may be indicative that Luffy is exerting dominance over Yakei. 

If Yakei's rule persists, experts like Mr. Kaigaishi will have a once-in-a-lifetime opportunity to research how Japanese macaques fare in a female-led community.

According to Kaigaishi, “Japanese macaque society is so dramatic and unpredictable," which is why many love to observe them.