Crested black macaques are remarkable for their extraordinarily large groups, sometimes numbering over a hundred. What truly sets them apart is their unique character, which is deeply connected to their home environment.
These macaques inhabit the rich forests of northern Sulawesi, which lie directly in the path of the monsoon. For months, torrential rains batter the forest. However, it is these very rains that contribute to the development of behaviors in the macaques that are strikingly similar to those in humans.
From a young age, the macaques have much to learn, starting with the basics such as perfecting their climbing techniques. Most importantly, they must learn their social etiquette. For the crested black macaques, lip smacking is a request for a hug and shows a desire for friendship. Blowing kisses and sharing cuddles are not just reserved for close family members; anyone in the troop can join in. These macaques are among the most affectionate monkeys on the planet.
One reason for this high level of affection is the abundance of food brought by the monsoon. With over a hundred varieties of fruit available, there is more than enough to go around. This abundance means they don’t need to fight over food. Instead, they can focus their energy on positive activities such as forming friendships and exploring their forest home.
A discovery often draws them all close, such as a tiny casualty on the forest floor. Their sensitive behavior in such moments can appear touchingly human. The character of the crested black macaques is a direct result of the riches that the monsoon brings, providing them with abundant food and allowing them to enjoy the good things in life.
In the highlands of Ethiopia, groups of mothers and their young gather to form troops of up to 800 monkeys. One of these groups is led by a male gelada named Janada, whose hands are usually busy plucking grass rather than grooming. To maintain social bonds, geladas have become the most vocal of all monkeys. Their gossipy banter can sound to scientists like sentences with words or even names for each other. Most experts agree that this chatter is often used to diffuse tension.
Geladas live in a highly tense environment. Young males form gangs that attempt to steal females from the established family harems. Each harem is guarded by a single male, known as the harem master. These “spare boys” try to lure females away, hoping the harem master won’t notice. The males often flash their teeth at each other and may fight, though it’s usually more about showing off in front of the females.
There is a lot of flirting on both sides, and when an innocent-looking female is tempted to wander away from her guardian, the harem master has to decide what to do. Females often sneak off for secret affairs, which blatantly challenge his authority. When caught, the illicit couple might just sit together. The suitor may use his hand to hide his grimace, likely hoping to avoid trouble.
This kind of social problem, where animals use their brains to control society, is called Machiavellian intelligence. The term comes from a 16th-century courtier who wrote about manipulating political power. Instead of attacking, a male gelada might grab a baby monkey since etiquette dictates that no one attacks someone holding a baby. Mothers quickly scoop up their youngest when danger looms, using them as living shields.
In one encounter, two males face off. The family man backs towards a loyal wife, calling for support. One youngster switches from mother to father, which should calm things down since the father’s protection increases with a youngster attached. However, things can go wrong; if the youngster slips off, the family becomes frantic, and the harem master loses his protection.
In a typical scenario, the bachelor is driven off with help from the mothers. However, the harem master, responsible for guarding the young, knows he’s in trouble if the infant dies. The mothers may withdraw their support, jeopardizing his position.
Humans, like geladas, wrestle with similar social and competitive problems. Our complex social interactions reflect those of these fascinating primates, highlighting our shared nature of being both social and competitive.
