There are many factors that influence the gorilla’s ethology: habitat, phylogeny, life history, demography, access to food, predatory pressure, social relationships, etc. An aspect as basic as the gorillas wash the fruit may be intimately related to some aspects mentioned above, or not.
A good number of scientists have dedicated part of their lives to studying these primates, how they relate socially, whether or not they have their own culture … The complexity of the gorilla’s ethology is such that, after decades of research, there are still many doubts to resolve.
Do all gorillas eat fruit?
The different populations of gorillas and, therefore, their subspecies, they feed on the different resources available in the area where they live, east or west of the Democratic Republic of the Congo.
Usually, Gorillas are herbivorous animals, although in their different aspects. There are populations of leafy gorillas, that is, they feed mainly on leaves, especially succulent plant leaves. These vegetables form almost 70% of the diet of these gorillas. On the other hand, other gorilla populations are frugivorous and feed mainly on fruits.
Despite this, The diet of the gorillas also changes according to the time of the year, because with the hours of light, rain and temperature, the availability of food varies, although we can summarize that these animals feed on:
Gorillas learn what to eat and what not when they are young, before weaning occurs. Juvenile individuals learn what they can eat playing with the plants around them, always under the watchful eye of the rest of the group. In addition, through observation they mimic the behavior of their elders.
Wash the fruit, innate or learned behavior?
Not only gorillas wash the fruit. All primates do, even other animals that do not belong to this order of mammals. Washing the fruit does not necessarily imply the use of water. Needless to remove the dirt that is above.
At first it was thought that the fact that gorillas wash the fruit was part of the culture of these hominids, that is, it was taught from parents to children.
However, it has been proven that most of the captive gorillas, who had never been with their wild relatives, washed the fruit, even though no relatives had ever taught them. It is true that each animal washed the fruit in a different way and tried to show the rest the best way.
How does gorillas benefit from washing the fruit?
All social animals, and even non-social ones, are groomed. Eliminating dirt from the body and possible parasites is essential to stay healthy and look good. Animals whose appearance is neglected will be less likely to find a partner and, therefore, to reproduce. To look good outside it is important to take care of the interior, and animals know it.
Some species of bears know what plants to eat when they feel sick to the belly. Chimpanzees take a series of vegetables to help eliminate internal parasites, just like other monkeys.
Eating dirty foods can make us sick, so cleaning them causes bacteria and parasites to be eliminated. The fact that gorillas wash the fruit innately may mean that this is recorded in their genome and that those ancestors who performed this action could reproduce with greater success.
The gorilla family is not the only way these primates have to relate: a study discovers that they have very complex friendship relationships. Read more “