Chimp groups are ruled by a 'high social value' female -- not an 'alpha male'. The males have a hierarchy of their own, but they all take turns fucking the higher value females -- that's why they have massive balls and produce loads of sperm -- to displace that of rivals. They can go up the ranks by successfully mating a high value female.
Orangutans are interesting -- 'dominant males' get the huge facial 'flanges', huge muscle mass, 'cape-like' fur and a massive throat sac. They're some of the most impressive animals on Earth... people talk about silverback gorilla strength, but I've worked with both, and flanged male orangs are so strong that you have to spot-weld nuts on their enclosures, or they just undo them with their fingers – even if you torque them with a scaffold pole on the wrench!
![[Image: Hercules-fullbody1.jpg]](http://http://orangutan.or.id/wp-content/uploads/2012/04/Hercules-fullbody1.jpg)
Not all male orangutans will undergo this second puberty type metamorphosis, and it can be triggered at any age, by the absence of another flanged male.
We had a young male that lived with his Dad, and stayed right around 50kgs, just looked like a rangy female at 12 years-old. Once introduced to a group of females with no other adult male, he grew significant muscle-mass and the secondary sexual characteristics within months.
The flanges seem to act like a megaphone: like when you cup your hands around your mouth to project your voice. Obviously, if you're swinging through the trees, you need both hands, so those flanges do the job of projecting the dominant male's 'long call', which is also aided by the throat sac.
These males are solitary, and the calls of the biggest ones basically suppresses the other males in the area, and tells females which way he's headed – so they can hang out and wait to be mated by him! Then he goes on his merry way.
However, the non-flanged males also get to mate – sort of. They basically act like females until the girls let their guard down, and then employ a 'surprise rape' strategy. They aren't gentle, either!
Interestingly, I worked on a film with an American anthropologist (I can't remember his name) and he gave me this insight, based on his observations over four decades of observing primates in all settings:
In primates that pair monogamously – like Gibbons in the apes and various small monkeys – males and females are hard to tell apart, size-wise and otherwise, visually.
In apes and monkeys where one male takes various female partners, or maintains harems, the male is bigger and carries more muscle mass – is essentially 'weaponised' (I'm British, hence the spelling). The more partners they 'manage' (plates they spin) the bigger the visual dimorphism. Gorillas are a clear example, and Drill Monkeys are the extreme example – they live in 'supergroups' with one massive (four times the size of a female) brightly coloured dominant male with HUGE canine teeth.
Now, we humans are a species of ape. We're also sexually dimorphic – males are meant to be bigger and stronger, right (I'm bigger and stronger than any chick, I guarantee). That implies that, biologically, we are not evolved for monogamy.
By the way – I was one of the guys who shot
this birth footage (BE WARNED it's very graphic) and got to know the particular group of orangutans very well.
The male (Dagu) was 130 kgs (like me) and the same age as me – I was startled by the parallels between us, and as tough as I thought I was, this guy was the natural alpha, personified.
The longer I spent around him, the more impressed with him I was. He used
just enough energy, or dominance, or effort of any kind, to do anything he had to do... and he handled his business with his girls in a way that any guy would envy.
If he had to, he could summon strength at levels you can't imagine (I saw him pinch grip the lip of a FULL fifty gallon drum of water and throw it across a moat that we used a small boat to cross!), but he could delicately peel the skin off a plum. Unreal creatures... I hate that they are so endangered in the wild.
Rick
