Mating and reproduction in gorillas is a thing of curiosity for both wildlife lovers and those that are not. A few lucky people have seen the gorillas mating in Uganda and Rwanda during the gorilla trekking adventures in the jungle, much to their amusement seeing how human-like the gorillas mate. Like humans, gorillas can have face to face sex, with the female lying down on her back and the huge silverback gorilla on top delivering slow strong thrusts! Gorillas also mate by way of the female turning and leaning over with her face to the ground and the male copulating from her behind/back (dog-style).
In fact, mating gorillas is one of the most trending videos about gorillas on social platforms like youtube (seeing how human-like they mate, one cannot help but think that these videos should be flagged as porn or nudity).
But away from satisfying the curiosity (out of perversion or not) of some people, you will find mating and reproduction in gorillas an interesting topic and below you can learn all about it. Gorillas and humans share up to 98% DNA so there are similarities in the mating and reproduction between gorillas and humans.
Male gorillas reach sexual maturity by 10 – 13 years, and females starting ovulating around age 6 but are fully sexually mature by age 10 years when they can conceive.
The silverback gorilla that is the dominant male and leader of the group has the mating rights in the group. He mates with all female gorillas in the group as soon as they reach ovulation.
However other low ranking adult males may also have a chance to mate with a female if she is turned away by the dominant silverback. Also, mature females sired by the dominant male, to avoid inbreeding with the father will choose to mate with other adult males in the same group.
Gorillas avoid inbreeding, so once a young female matures she will leave her father’s family to avoid breeding with him. She will leave her father’s group to join another group in the jungle where she can mate with the silverback there, or else she will stay single in the jungle until she can join a new group. Also, within a group, maturing young females leave their mother’s unit to join other social units in the group; this eliminates any possible breeding between siblings in the few cases where a female gorilla may not mate with the dominant silverback and instead mates with another male in the same group.
Gorillas mostly mate for breeding purposes, but mating for leisure and favor has also been observed in gorillas. The female in most cases starts the mating process. When in estrus and ready to mate she will approach the dominant male and indicate to him she wants to mate by making a long eye contact and a mouth gesture to communicate her need mate to which the male shall oblige. Sometimes the dominant male may not react to the female’s advance, and when this happens the female may give an opportunity to other males in the group to mate with her.
The dominant silverback gorilla can also start the mating. He will approach a female in estrus and make vocalizations or physically pull her over in way that indicates to the female his intention to mate and the female shall submit immediately.
Studies show that actually gorillas can mate with no intention for reproduction. Female gorillas use sex to find favor from the dominant silverback. On the other hand male gorillas have also been observed to mate with females that are not ovulating or not in estrus, drawing the conclusion that they are simply having sex for leisure.
Menstrual cycle of gorillas is similar to humans with a 28-day estrus cycle.
When the female gorilla is impregnated the gestation period is about 255 days. On the other hand the human gestation period is about 265 days on average.
After birth, the mother gorilla will keep full physical contact with her baby for about 4 – 5 months, during which time the baby clings onto the mother’s body all the time. Weaning the baby will start from around one year and by around 30 months the young gorilla are fully weaned and becomes semi-independent spending on half the time with the mother.
The mother gorilla resumes estrus at weaning.
Females resume estrus at weaning so will be ready after mating after fully weaning the young gorilla which is around at age 2 – 3 years. Female gorillas are weaned earlier than the males. The mother may also extend weaning of the male gorilla to improve his chance of becoming the dominant silverback.
The relatively long time for the female gorilla to get to estrus results to a relatively low birth rate among gorillas.
Like in many species in the animal kingdom, male gorillas do not tolerant young gorillas that were sired by another gorilla. So, once a new silverback gorilla becomes the dominant male and leader of the gorilla group he will go out to kill babies that have not been weaned. The new silverback does this to shorten the time for the female gorillas to come into estrus again.
So soon after, the females will be pregnant again with the dominant silverback’s offsprings with his genes.