Trends in human evolution that shaped us
Venus figurines in context.
Part 2-1
Modern man has a body whose parts have their origin in the more or less distant past and whose analogies can be traced, to varying degrees, in both closer and more distant ancestors. The same applies to the human psyche.
For example, disappointment from an unfair reward can be observed not only in humans, but also in chimpanzees or dogs. One of our oldest legacies from prehistoric times in our psyche is the sense of being treated fairly.
Cooperation suppresses aggression and develops the brain
Another legacy of prehistory is the ability to cooperate. The potential for cooperation was already present when we diverged from our chimpanzee ancestors.
Two species of the chimpanzee, the common chimpanzee and the bonobo chimpanzee, diverged not long after the divergence of the branch that led to humans. As it turns out, our common ancestor with chimpanzees was anatomically more similar to the bonobo chimpanzee (Pan paniscus) than to the common chimpanzee (Pan troglodytes). It is quite possible that they were more similar psychologically, with the common chimpanzee taking the path of increasing aggression and the bonobo chimpanzee taking the path of decreasing it.
Similarly, the human ancestor (and then the emerging human race) embarked on a path of decreasing aggressiveness and increasing tolerance towards other members of its species, thus leading to the possibilities of more intensive cooperation and closer mutual interaction.
The ability to increasingly cooperate and adapt one's behaviour to benefit the entire group has proven itself in human evolution and has proven to be a good way to face adverse circumstances. Emerging (pre-)human groups that favoured aggression and competition leading to non-cooperation were unsuccessful and died out compared to those that cooperated. This resulted in the selection of genes that reduced aggressiveness. In addition, cooperation proved to be suitable for the ancestors of modern humans to be able to adapt increasingly to different types of environments and, therefore, to more easily survive rapid changes in conditions in the place where they lived and to successfully move to new areas. By reducing aggression and increasing the scope and intensity of cooperation, the brain developed and grew, and with it the intelligence of our ancestors.
Human exceptionality: Two kinds of empathy
Close cooperation led to the development of empathy. We also inherited the ability to empathize from animals, but the mutual proximity of cooperating individuals created very favourable conditions for its development. The spread of empathy was also aided by the fact that the ability to empathetically assess the needs of young children increased their chances of survival, or that an empathetic partner was more desirable than one who did not show empathy.
Humans are the only primates to have developed two types of empathy. The first type of empathy is a reaction to the suffering of another group member, and is manifested by an attempt to comfort the affected person. This type of empathy is inherent to apes as well as, for example, elephants.
I'd like to give an example from the book "Mama's Last Hug" by primatologist Franz de Waal. He writes about how adopted chimpanzee Joni treats his caretaker: "Joni was emotionally disturbed when she started to mimic weeping. He ceased his play immediately and tried to fnd the reason of her cry and he strived to comfort her."
The second type of empathy is not a reaction to suffering, but is manifested by an individual spontaneously helping another if they feel that they can benefit from it in some way. The goal is the well-being of the entire group. Such empathetic behaviour is called other-regarding preferences. This type of empathy cannot be found in any ape, but is found in animals that live in groups characterized by an arrangement called "cooperative breeding". The animals closest to humans in terms of development, in which this type of arrangement occurs, are monkeys from the family of marmosets (Callitrichidae). They are the smallest monkeys and live mainly in the treetops of South and Central America.
Empathy and altruism bring group members closer together
Empathy leads to altruism, i.e. behaviour in which an individual helps others or another individual at their own expense. The whole group benefits from such behaviour. Another type of altruism is reciprocal altruism, which can be expressed as "I will help you today, and you will help me when I need it." This kind of altruism also strengthens cooperation among the entire group because it requires mutual trust and what we might call decency or reliability. An individual who fails to do so will lose credibility in the eyes of all members of the group, with all the consequences that this will have for him/her.
Cooperative breeding in hunter-gatherers
Cooperative breeding means that the young are cared for, to a greater or lesser extent, not only by the parents, but also by other related and unrelated members of the group. They are called "alloparents", co-parents. In professional Czech, the term "alloparental behaviour" is used, and I have also noticed the term "aunt behaviour". Not all caregivers are necessarily adults, "co-parents" also include older or teenage children. This type of care for offspring has also been documented by researchers among contemporary or recent hunter-gatherer groups.
It is believed that alloparental behaviour was already present in Homo erectus, an archaic human dated sometime around 2 million years ago. Some researchers date the origin of alloparental behaviour to an even earlier time.
All in one: cooperative reproduction, altruism, and both types of empathy
It can therefore be said that modern humans, Homo sapiens, and their archaic ancestors, have lived since at least 2 million years ago as hunters and gatherers in groups practicing "cooperative breeding", and were characterized by empathy and altruistic behaviour.
About 2 million years ago, there were cases where an individual affected by illness or injury was able to survive thanks to the care of other members of the group.
This "all in one" led, through extensive collaboration, to a continuous development of the brain that had had no parallel in the animal kingdom on planet Earth until then. Such abilities allowed us to adapt to a variety of natural environments, and venture out into the world.
The whole process took a very long time, of course, and people had to face very difficult natural conditions of the Ice Age, especially in areas further from the equator. Europe was finally permanently settled by modern humans Homo sapiens about 43,000 years ago.
Following part: 2-2 Lifestyle of hunters and gatherers of the Golden Age of Venus Figurines.
Previous part: 1-3 A Brief history of the settlement of Europe and its surroundings.
Literature
Books
1.
Sarah Blaffer Hrdy:
Mother Nature.
The Ballantine Publishing Group, New York, 1999
2.
Frans de Waal:
Mámino poslední objetí. Co nám emoce zvířat prozrazují o nás samotných.
Práh, Praha, 2020
(English original: Mama's Last Hug: Animal Emotions and What They Tell Us about Ourselves. W.W.Norton and Company, 2019)
3.
Brian Hare, Vanessa Woods:
Survival of the Friendliest: Understanding Our Origins and Rediscovering Our Common Humanity
Random House, New York,2020
Articles
1.
F. Range, L. Horn, Z. Viranyi, & L. Huber:
The absence of reward induces inequity aversion in dogs.
Proc. Natl. Acad. Sci. U.S.A. 106 (1) 340-345,
https://doi.org/10.1073/pnas.0810957105 (2009).
https://www.pnas.org/doi/10.1073/pnas.0810957105
2.
Rui Diogo, Julia L. Molnar, Bernard Wood:
Bonobo anatomy reveals stasis and mosaicism in chimpanzee evolution, and supports bonobos as the most appropriate extant model for the common ancestor of chimpanzees and humans.
Scientific Reports 7, 608 (2017). https://doi.org/10.1038/s41598-017-00548-3
https://www.nature.com/articles/s41598-017-00548-3
3.
Hominoid Psychology Reserch Group, Max Planck Institute for Evolutionary Anthropology:
3 Chimps. Chimps and Bonobos.
https://www.eva.mpg.de/3chimps/files/apes.htm
4.
Constantina Theofanopoulou, Alejandro Andirkó, Cedric Boeckx , Erich D. Jarvis:
Oxytocin and vasotocin receptor variation and the evolution of human prosociality.
Comprehensive Psychoneuroendocrinology
Volume 11, August 2022, 100139
https://doi.org/10.1016/j.cpnec.2022.100139
5.
Kaminski J, Stengelin R, Girndt A, Haun D, Liebal K.:
Understanding others' preferences: A comparison across primate species and human societies.
PLoS One. 2024 Jan 17;19(1):e0295221.
doi: 10.1371/journal.pone.0295221.
PMID: 38232055; PMCID: PMC10793897.
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0295221
6.
J.M. Burkart, E. Fehr, C. Efferson, & C.P. van Schaik:
Other-regarding preferences in a non-human primate: Common marmosets provision food altruistically.
Proc. Natl. Acad. Sci. U.S.A. 104 (50) 19762-19766, https://doi.org/10.1073/pnas.0710310104 (2007).
https://www.pnas.org/doi/10.1073/pnas.0710310104
7.
Harris RA, Tardif SD, Vinar T, Wildman DE, Rutherford JN, Rogers J, Worley KC, Aagaard KM.:
Evolutionary genetics and implications of small size and twinning in callitrichine primates.
Proc Natl Acad Sci U S A. 2014 Jan 28;111(4):1467-72.
doi: 10.1073/pnas.1316037111.
Epub 2013 Dec 30. PMID: 24379383; PMCID: PMC3910650.
https://www.pnas.org/doi/10.1073/pnas.1316037111
8.
Miller, Cory T. et al.:
Marmosets: A Neuroscientific Model of Human Social Behavior.
Neuron, Volume 90, Issue 2, 20 April 2016, Pages 219-233
www.cell.com/neuron/fulltext/S0896-6273(16)30007-1
9.
Karin Isler and Carel P. van Schaik:
How Our Ancestors Broke through the Gray Ceiling: Comparative Evidence for Cooperative Breeding in Early Homo.
Current Anthropology , Vol. 53, No. S6, Human Biology and the Origins of Homo (December 2012), pp. S453-S465,
https://www.jstor.org/stable/10.1086/667623
10.
Burkart, J., Allon, O., Amici, F. et al.:
The evolutionary origin of human hyper-cooperation.
Nature Communications 5, 4747 (2014)
Published27 August 2014
DOI https://doi.org/10.1038/ncomms5747
https://www.nature.com/articles/ncomms5747