In science there are two ways to know what human beings were like before. One consists of looking at the remains of the past, that is, collecting fossils and remains of our ancestors, comparing them and deducing what they must have been like.
The other consists of comparing our behavior with that of the species most closely related to ours, that is, those that are part of the order of primates.
Primatology is a very interesting scientific discipline which, in addition to taking into account the fossil record, focuses its efforts on understanding how our relatives, chimpanzees, bonobos and gorillas, behave to understand why we are the way we are. Let’s look at it further.
What is primatology?
Primatology is the scientific discipline dedicated to studying primates, both through research on their natural behavior and through the fossil record of extinct primate species.
Primates are a taxonomic order that includes plantigrade mammalian animals with five fingers, which end in nails on their extremities and have thumbs that are opposable to the rest on their upper limbs. Within this order the Homo sapiensthat is, our species, is included
As a scientific branch, primatology encompasses knowledge from many disciplines such as biology, anthropology, ecology, psychology, philosophy and many more.
From all these branches he is able to extract knowledge such as how the organs of primates work, what their social behavior is, to what extent they are capable of thinking, if they can acquire human skills such as language…
History of this scientific discipline
Long before modern molecular biology and even before Charles Darwin and his well-known work The origin of species (1856) in which he already indicated his suspicions about the primate origin of Homo sapiens, Carl von Linné (1707-1778) was classifying our species in the same group as the ape lineage
This classification was made based on how similar the species were to each other. She saw that monkeys, chimpanzees and orangutans are very similar to human beings, and for this reason she put them in the same taxon.
Linnaeus lived long before Darwin and his modern evolutionary ideas, but certainly something must have made him think about the fact that he had seen similarities not only between these primates and humans, but also between other species such as dogs and wolves or cats and tigers.
He was a great visionary in this regard because, without having tools such as molecular biology at his disposal, knew how to closely place species such as the chimpanzee and the Homo sapiens which we know share about 98% of the genetic material.
After Darwin and his work and all the scandal that was generated, the scientific society became increasingly aware of the evolutionary closeness between these monkeys and humans. However, despite this knowledge, It was not until the 1920s that interest in living, well-functioning primates began to emerge Until that time, scientific efforts had focused on studying fossil remains of hominids and possible links between early primates and the first Homo sapiens.
The reason why dusty lifeless remains should have been studied rather than gorillas, chimpanzees and other primates that could be seen full of life is surely due to the difficult acceptance of evolutionary facts at the time.
Based on the mentality of the time, the idea of descending from the monkey was something unpleasant, so it must have been more difficult for the proud scientific community to search for answers to what human beings are like by analyzing the behavior of little hairy men who go from branch to branch.
But despite all this The first studies with modern primates as protagonists ended up being carried out At first they focused on the behavior of chimpanzees and how they were able to solve different kinds of problems. Later the observation fell on the baboons, discovering that sex was a fundamental basis of their society and, surely, also of that of Homo sapiens.
At a time when the codes that regulated experimentation were non-existent for experiments with humans, these were unthinkable for animals. This is why more than one scientist without many scruples and trying to see if he could play God, carried out crossbreeding by artificial insemination of higher primates with human beings.
Fortunately, this sin against nature did not give birth, since, despite the similarities between primates, the genetic differences are large enough so that there is no hybridization of any kind.
As time went by, it became clear that It was unwise to study primates solely in aspects such as their biology and psychology in extremely controlled laboratory conditions In order to know how similar they are to human beings, it is necessary to know how they behave, and the only way for them to do so naturally is in their natural habitat.
For this reason, the tendency of primatologists was to abandon the cold animal experimentation rooms to move on to field work in Africa, where the most interesting species of primates are found.
What data do primates offer us?
Regarding biology, there are many things we can learn about ourselves by observing the anatomy of primates and how it has changed throughout the history of evolution. It is here where We can talk in two ways to compare ourselves with them: analogy and homology
Analogy
The analogy helps us to infer the similar functions of the organs and other parts of the body of two or more species, comparing their shape. So, It is through the comparative study of analogy that we can know how extinct species acted or moved in life comparing their fossil remains with the bone structures of animals that still exist.
If a characteristic is observed that has a particular function in a species, it is assumed that the same function was also present in the extinct species, as it was observed that its fossil remains also presented that anatomical characteristic. With all this we can draw conclusions about how an extinct primate behaved by establishing an analogy with a similar current form of life.
Homology
Homology is used to reconstruct family trees of species evolution It involves establishing the relationship we have with a common ancestor based on the similarity of shapes or limbs, how these evolved until we obtained the characteristics that are present today, in this case, in our organism. Between non-human primates and Homo sapiens, several common structures can be found that differentiate us from other orders of mammals.
In primates you can find five fingers on each hand and foot, as well as some characteristic bones in the skeleton, such as the clavicle. The fingers are prehensile, having visible pads and flat nails instead of the claws that we can find in other mammals as are lions, cats or dogs.
As we climb the evolutionary tree we can see that our snouts become smaller, flattened and become the nose and mouth as separate parts.
In addition, we have stereoscopic vision, that is, we have superimposed vision in both eyes, and it is this sense that has been evolving in a very noticeable way, to such a point where smell has been losing importance.
In all primates It can be seen that the brain is a fairly advanced organ compared to other mammals The brain has been undergoing progressive development, especially in some areas such as the cerebral cortex, so important for human beings that it is what basically gives us our intelligence as we understand it.
Another very interesting aspect that other primates share is the gestation period, which is characterized by being long (humans 9 months, chimpanzees 7 months, gorillas 8 months). Furthermore, it has been observed that among primates we tend to give birth during the night.
Important figures
The most prominent figure in primatology is undoubtedly the English primatologist Jane Goodall This scientist, Member of the Order of the British Empire and the French Legion, dedicated herself to studying for more than five decades (she began in 1960) the social ties of chimpanzees in Gombe Stream National Park in Tanzania, contributing with great discoveries.
His determination and conviction that he would be able to observe behaviors that no other researcher had observed before earned him wide recognition. Additionally, Goodall is known for her work on animal welfare.
Another figure is that of Dian Fossey , whose work at Karisoke Research in Rwanda demonstrated that gorillas can habituate to the presence of humans. Fossey learned that female gorillas are sometimes transferred between groups and that gorillas are capable of eating their own feces to recycle nutrients.
The third great figure of primatology is Birute Galdikas, who spent nearly 12 years trying to get a group of orangutans from Borneo, Indonesia, accustomed to his presence. Galdikas used modern statistical techniques to finish his doctoral thesis in 1978 in which he explained the behavior of orangutans and their interactions.