THE ROLE OF WORK IN THE TRANSITION FROM APES TO
HUMANS
ARIZONA STATE UNIVERSITY
ASM 104 - BONES, STONES, AND HUMAN EVOLUTION
SPRING 2024 - WEEK 1
Introduction:
The 2004 discovery of Homo floresiensis fossils in Liang Bua, Flores, Indonesia,
challenged old Darwinian beliefs. The cranial capacity of floresiensis was only 380-410 cc;
not much different from the australopithecus genus that lived 4-2.5 million years ago. The
same goes for their body size. The difference is that floresiensis lived about 100 to 12 rts
(thousand years ago); crossing lifetimes with Homo sapiens. Floresiensis was also perfectly
bipedal-terrestrial adapted and produced stone tools. Experts agree to classify floresiensis
into the genus homo. The only debate is whether they belonged to a dwarfed Homo sapiens
or a separate species that was on the evolutionary ladder within a very close period to the
existence of Homo sapiens2.
What belief did the discovery of floresiensis challenge? Namely, that the marker of
humanity is not the size of the skull associated with cognitive capacity. Since Darwin in the
nineteenth century Up until the 1970s, evolutionary theorists believed the size of the skull
was the primary marker of humans. In addition, since Darwin there has also been a general
belief that human traits such as anatomy supporting bipedalism, tool production, large brain
capacity, and communication through language emerged simultaneously. In mid-1876, five
years after Charles Darwin's book The Descent of Man, which proposed the theory of
simultaneous evolution, Friedrich Engels wrote an essay entitled The Role of Labor in the
Transition from Ape to Man. It was here that Engels formulated his theory of the course of
human evolution that differed from Darwin's. According to Engels, the belief that the
development of the brain and the cognitive abilities on which it is based is the first driver of
evolution towards humans comes from an idealistic view of evolution1.
Engels did not deny that cognitive capacity and the evolution of the quantity of brain
organs was one of the important features of evolution towards humans. However, these
qualities are only one of the features of the most recently evolved hominin family. Rather
than being a cause, the development of the brain and its cognitive qualities is the result or
effect of ape-to-human evolution, which was preceded by changes in bipedal anatomy and
the liberation of the hands from their weight-bearing function in locomotion. The
capabilities of the modern human brain are the result of the last qualitative change in the
evolution of quantitative changes that took place in the dialectic of hominin relationships
with their natural environment in which work played an important role.
Engels' narrative of the course of human evolution was first laid out in his collection
of writings, The Dialectic of Nature. In the introduction to this work, Engels wrote: "Man
also came into being by differentiation. Not only are they individually differentiated from
one egg to being the most sophisticated organism that nature has ever produced, no, but also
historically "1.
This chapter will review one by one the differentiations that Engels argued occurred
throughout hominin evolution and led to the evolution of our species, Homo sapiens.
Context and Summary of Engels' Theory in the Role of Work :
Modern anthropology developed as a scientific discipline from the merger of two
classic nineteenth-century fields of inquiry, namely "physical anthropology" and
"ethnology". Both had one goal: to explain human origins, similarities and diversity. In the
context of the Age of Enlightenment, anthropology was the European bourgeoisie's means of
understanding itself amidst the optimism of their revolutions that succeeded in politically
subduing the old feudal powers. Physical anthropology was primarily concerned with the
diversity of human physical appearance. At the time, physical anthropology paved the way
for the European bourgeoisie to interpret that they were biologically different from the other
nations they were colonizing. Physical anthropology became a kind of scientific justification
for a kind of racism in the midst of Enlightenment opti- mism, which in Hannah Arendt's
analysis2, was one of the most important ideologies underlying imperialism. The peoples of
Africa, Asia and the Americas were biologically (that is, by nature) considered inferior to
Europeans and therefore legitimate to enslave and colonize.
Anthropology in general and physical anthropology in particular, as sciences born
from the womb of the bourgeois revolution, were strongly influenced by the thought of
Charles Darwin. Darwin's works, especially The Decent of Man published in 1871, further
encouraged the investigation of human origins. Not only his biological evolution, but also
his culture. As a scientific discipline, paleoanthropology, a section of physical anthropology
that deals with the fossil remains of early humans, was still a child in Engels' time1. Not
many fossils were found. The fossils found in 1829 in Belgium, 1848 in Gibraltar and 1856
in Germany were still very limited. Ancient tools and animal fragments were also only
found in 1859 in England and a few places in Europe and Asia2. The significance of these
findings was also not considered until well into the 20th century3. In addition, opposition to
the theory of evolution from the church-backed aristocracy was still strong. In the midst of
the scarcity of material evidence and the many social pressures against the theory of
evolution, Engels wrote his essay. In such a context, it is not surprising that some of the
evidence Engels presented sounds ridiculous to today's paleoanthro- pologists. So, Engels'
theory of human evolution is essentially speculative or at least quasi-historical.
Engels, like Marx, based his theories of man on the view that man and nature are not
two completely separate things. Man and nature are one single, inseparable entity. Man, with
his blood, flesh and brain capacity, belongs to nature and can only be understood in the
context of being in its midst.
Engels' thoughts on anthropology are not numerous. The most famous is of course
The Origin of the Family, Private Property and the State (1884). Similarly, Engels' thoughts
on paleoanthropology only appear in The Role of Work, a little in The Dialectic of Nature,
and at the beginning of a long essay entitled The Early History of the German Nation4.
Like Marx, Engels praised Darwin. For Engels, since Darwin published his works,
human origins could no longer be understood by referring to "the books of the Law of
Moses "1. The discovery of ancient human fossils and tools since the early 19th century
shows that humans have existed on earth far beyond 6000 years ago, the year that
religionists believe was the year of Adam and Eve's creation. Although he admired and
followed Darwin's theorization, Engels' understanding of the course of human evolution was
different. For example, Darwin emphasized the continuity between the development of
biological differentiation of higher primate species to the emergence of humans. Darwin
emphasized quantitative change and understood it in terms of the gradual movement through
which the change to modern man took place. Engels, meanwhile, believed in a qualitative
leap as well, namely the disconnection of cultural evolution from biological evolution.
Engels emphasized the existence of something unique in the development of man as a
species. Indeed, like Darwin, Engels recognized that the higher apes had the basic biological
preconditions for the transition - the development of upright posture, stereoscopic vision, a
long childhood and care by the mother, the development of speech organs, and the
development of a free hand with a thumb opposite to the other fingers. However, Engels
applied a materialist dialectic that explained development in terms of material changes that
transformed higher hominins into qualitatively different species. Qualitative change occurs
when the quantitative change in material processes in homi- nin evolution reaches a
threshold.
Rather than accepting the common view that development The brain being the
primary and earliest step in human evolution, Engels argued that the first step should be to
descend from the trees followed by standing upright and living on the ground by human
ancestors. Standing upright and moving on the earth's surface on two legs (bipedalism-
terrestrialism) freed up the hands and this enhanced the ability of humans to use and make
tools at a later stage of evolution. This change in turn led to changes in the makeup of the
hand so that the hand became not only an "organ of labor" but also a "product of labor".
In human evolution, work is the threshold that separates humans from apes. Work is
rooted in material processes, but then transcends them. In dialectical terms, work is the
negation of nature that has elevated humanity beyond the physical realm, although it does
not necessarily make humanity outside of nature entirely. Work has made man an actively
transforming part of nature and therefore a transforming part of it. Man, Engels explained, is
the only animal that devotes itself to work-a conscious interaction with nature that aims to
transform nature for its benefit, but at the same time transforms man.
Engels' other criticism related to Darwinian biologism which influenced the
emergence of Social Darwinism as the ideology of the European bourgeoisie. Especially its
impact in economics and politics. In The Dialectic of Nature, for example, Engels said that
"Darwin did not know what bitter satire he was inflicting on man, and especially on his
countrymen, when he pointed out that free competition, the struggle for life, which
economists celebrate as the highest historical achievement, is regarded as the normal state of
the animal kingdom "1. Darwin's ideas became the narrator of racism and working-class
oppression. The powerful and the rich are legitimate because they are the most fit to exist;
they are the winners in the natural world of free competition and struggle for life.
Transition to Terrestrial Movement:
In the essay The Role of Labor, Engels states that "when walking on the ground, the
apes begin to neglect the assistance of their hands and adapt themselves rather to standing
upright. This is the decisive step in the transition from ape to man "1. Here, like all
nineteenth-century material, Engels believed humans evolved from apes. The first step in the
evolutionary trajectory towards humans began with habitat differentiation, from living in
trees (arboreal) in the wilderness to living on the ground (terrestrial) in more open
landscapes.
Modern paleoanthropological findings confirm that early hominins appeared at the
end of the Miocene Epoch. Contemporary genetic maps confirm that the hominin lineage
diverged from a common ancestor that descended the chimpanzee lineage some 8 to 5
million years ago2. This genetic analysis data is supported by the latest hominin fossil
findings, namely the species Sahelanthropus tchadensis (estimated to have lived 7-6 AD),
Orrorin tugenensis (lived around 6 AD), and Ardipithecus ramidus (lived between 5.8-4.4
AD). These transitional hominins, which lived from the late Miocene to the early Pliocene,
had mixed physical characteristics between apes and humans with a closer leaning towards
apes. The brain size of sahelanthropus, for example, was only 320-350 cc with primitive,
ape-like dentition although the fangs were smaller. The only thing that makes them
hominins is that the location of the foramen magnum, the hole where the end of the spine is
located in the skull, is more to the center than apes, which is located at the back. This means
they were bipedal. Their habitat was also a mixture of wilderness and open landscapes.
There is no doubt that they are not fully terrestrial. Their habitat and the arrangement of their
forelimbs suggest a mixed arboreal and terrestrial lifestyle3.
In Orrorin tugenensis, the bipedal tendency to live semi-arboreally in forest
environments or around lake or riverine forests is more obvious1. Similarly, the habitat of
Ardipithecus ramidus is more forest with grasslands interspersed with trees2. Bipedalism in
these oldest hominins is arguably still an "intermediate" form of adaptation to walking
upright on two legs. The skeleton of ardipithecus, for example, does not look like that of an
ape, but it is also not quite the same as later hominins.
From these recent findings, it seems that terrestrial life is not yet fully differentiated
from an arboreal lifestyle. Their lifestyle can be said to be semi-arboreal. It was not until
hominin species of the australopithecus genus that lived around 4-2 AD that the
differentiation of terrestrial from arboreal became clear.
The oldest Australopithecus lived between 4.2-2.8 AD. Their habitat is still a mixture
of open forest and scrub. Similarly, the habitat of Australopithecus afarensis and africanus
lived from 3-2.2 AD. There has been no significant increase in brain size in these early
australopithesin species. The afarensis brain, for example, was only about the size of a
chimpanzee brain, between 400-403 cc. Brain size only increased significantly in
Australopithecus gahri, which reached 430-450 cc. Their bipedal adaptations were more
pronounced than those of Miocene hominins. So was their terrestrial lifestyle.
The differentiation of terrestrial lifestyles began to be clearly recorded in the cousin
species of australipithecus, the paranthropes that lived in the late Pliocene to early
Pleistocene Period. They were more bipedal and lived on grasslands. The fully terrestrial
adaptation of paranthro- pus, apart from being indicated by the skeletal arrangement of the
body, is also from the teeth and facial muscles that indicate they are hard plant eaters,
including various types of grasses that live in open fields.
In early hominins, the arboreal lifestyle was still dominant, but in australopithecus
and paranthropus (also kenyanthropus) the terrestrial lifestyle emerged in place of the tree
life. This evidence supports Engels' view that the first step in evolution towards humans was
the differentiation of terrestrial lifestyles from arboreal ones, not brain enlargement. It was
later proven that it was this terrestrial lifestyle that became adaptive for the hominins of the
genus homo that descended later.
What happened to those early hominins that they had to start living at ground level?
Paleoanthro- pologists Boyd and Silk explain that: "Ecologically during the Miocene Epoch,
the Earth's temperature began to drop. This global cooling caused two important changes in
the climate of tropical Africa. First, the overall amount of rainfall falling per year decreased.
Second, rainfall became increasingly seasonal so that there were several months each year
when no rain fell. As the African tropics become drier, the tropical wet wilderness shrinks
and drier forests and grasslands expand "1. With the shrinking of the wilderness, early homi-
nin had to leave the trees more often. The shrinking of the wilderness created new selective
pressures for some apes. Our hominin ancestors in the ape world were forced to live and
forage more at ground level. The function of the hind limbs for climbing began to decline
and a new function for walking on the ground emerged. As they became more accustomed to
living at ground level, their body structure changed accordingly. Living on two legs led to
changes in the structure of the pelvis, toes and soles of the feet. The hips were adjusted to be
able to support the body as well as balance the use of the feet as the foundation for walking.
Bipedalism and Limb Differentiation:
The differentiation of terrestrialism from an arboreal lifestyle in early hominins was
an important laboratory for the emergence of more terrestrial hominins. Hominins that
succeeded in living terrestrially were those that further developed bipedal adaptations.
Bipedal adaptations allowed forelimbs to become freer from the "obligation" of supporting
the body. What is the significance of this differentiation of the forelimbs from the
hindlimbs? For hominins, the differentiation of limbs into hands and feet was a successful
response to major changes in their habitat1.
Engels asserts that limb differentiation allowed "the hands to become free and thus to
further attain greater flexibility and skill "2 leading to the manufacture and use of tools. In
early hominin species up to the appearance of Homo ergaster, the function of the hands for
climbing did not necessarily disappear. It was found that afarensis and its relatives slept in
trees like modern orangutans and chimpanzees do. This suggests that they still used their
hands for climbing on a regular basis. However, since living and sustaining themselves more
on the ground, hand functions were further developed to pick things up from the surface, dig
from the ground, and pick food from short trees on a regular basis. Millions of years of
hands-on experience to develop the hand beyond its climbing function then triggered
developments in the structure of the hand and fingers. The development of strong grasping,
picking and carrying abilities at a later stage enabled the evolution of hominins capable of
using tools. These hand and finger characteristics are also found in other primates, especially
modern apes such as chimpanzees or orangutans. The difference is that the hominin features
are in a unified intact with a bipedal skeletal arrangement. Another difference lies in the
ability of hominin hands and fingers to carry things over considerable distances. Although
apes are also capable of grasping, picking up and carrying, contemporary research shows
they are not capable of carrying over relatively long distances.
The ability of hominin hands to carry along with an evolved bipedal body structure
allowed for more effective tool use. Stone tools have not yet been found at the fossilized
sites of australopus and its cousins, but the first stone tools were only discovered during the
lifetime of hominin species around 2.6 ka. Although no tools were found with the early
hominin fossils, there is a good chance that they also used tools. This can be seen from
comparing their hand structures and the habits of modern apes, especially chimpanzees, who
are known to use tools. The australopithecines' hands show they regularly used tools.
Paleoanthropologists Melissa Panger et al.1 are also convinced that the size and morphology
of early homi- nin brains, which were slightly larger than those of modern apes, as well as
the morphology of their hands allow for tool use at least in those who lived around 3.2
millennia ago. The combination of new knowledge from primatology, phylogenetics and
fossil evidence pushes the tool-use date even further. Panger et al. suggest that early
hominins living between 8 and 5 AD may have used tools. The tools used were not only
crumbly and hard-to-fossilize materials, but also unmodified stone tools. Finds at the
Olduvai site suggest that the use and manufacture of tools dating back to 2.5 c.e. there
presupposes hominin experience over the previous million years of using and then
modifying stone for tools. What is found at Olduvai, according to Panger et al. is the result
of an intensification or spatial reorganization of the tool-related behaviors of earlier
hominins.
Related to tool use, the terrestrial-bipedal lifestyle generated new selective pressures,
namely the need to discover new types of food. Gathering food on the ground following
seasonal changes presupposes the transportation of food from the gathering area to the living
area. As the utilization of these new food types became more effective, it became necessary
to transfer the collected food. The life of early hominins, which still depended on forests or
trees to protect themselves from predators, as well as dependence on new food sources on
the ground, is difficult to imagine without differentiation between collection and
consumption activities. This differentiation would not have been possible without transport
tools as paleoanthropologist Gordon Hewes believes that: "the effective use of new sources
of food requires their removal from certain accessible distances, and only bipedal
locomotion, with arms and hands free for carrying, can achieve the maximum efficiency of
transportation "1. Here Hewes emphasizes the close link between bipedalism and the
ecological changes that eliminated some of the old food sources and brought new potential
food sources to the earth's surface, with a high probability of the emergence of food-
gathering carrying tools in early hominin life. In addition to freer hands, the ability to
transport food by hand may also be related to their smaller and weaker canine teeth. Unlike
other primates, which make extensive use of the mouth for transportation, the structure of
hominin teeth and jaws makes mouth transportation difficult2. Only with changes in
"technological behavior" The ability to carry by hand alone allowed hominins to adapt to
changes in their natural environment1.
With the increasingly common transport of food by hand, together with the possible
use of digging and carrying tools, hand specialization increased in hominin life. This
evolution of hand specialization, at a later stage, allowed hominins to further develop the
ability to use and make tools as Engels believed that: "hand specialization-this has an impact
on [the use of] tools, and tools have a particular impact on human activity, man's
transformative response to nature, [i.e.] production "2.
Homo ergaster or Homo erectus, which first evolved around 1.8 million years ago
from one of the australopithecus populations, is believed to have developed productive labor
through the use of tools. They no longer depended on the trees in the forest as a place to live.
They were already fully terrestrial. In many ergaster and erectus fossil finds, large animal
bones were also found. Although there is no strong evidence of hunting large animals, it is
certain that ergaster, the oldest species of the homo genus that is so similar to us, used stone
tools to cut the meat of large animals. Most likely they obtained the meat and bones of large
animals by scavenging from dead large animals3. In ergaster there is a strong possibility of
differentiation of production from consumption or the emergence of labor.
Some higher apes also use tools. Modern chimpanzees, for example, are known to
make and use tools from twigs or rocks to obtain certain foods. But even the most ancient
homo genus was far more advanced. They didn't just make and use tools. They also made
tools that were used to make other tools. The evolution of hominin hands also enabled the
production of tools and the transportation of tools from one place to another. Modern
chimpanzee hands, on the other hand, did not evolve toward the efficient transportation of
tools, so until recently chimpanzees only used tools where food was found and eaten1. As
hominins were able to make tools that were useful for making other tools, they began to
separate tools from organs. In other words, chimpanzees use tools without differentiation
between tools and organs because they rely on their organs to make tools, while hominins
have differentiation between organs and tools because they also make tools for tool
production. That is why ape tools never evolved despite biological evolution from early apes
to modern apes. In Engels' words, "animals ... also have tools, but only as part of their
bodies "2.
Tool Production and Social Organization:
As the differentiation of tools from organs developed, work emerged as a means for
hominins to explore, devote and utilize energy from nature. The activity of labor has opened
up previously unseen boxes of nature and mere potential. Engels believed that: "the
development of the hand, together with labor, expands man's horizon to new advances. Man
is constantly discovering new, previously unknown properties of natural objects "3.
The development of active and purposeful work or interaction towards changing the
surrounding nature through certain means, in the end led to new inventions that were useful
for human life. One of the most important advances was the creation and use of stone tools
which further "expanded human horizons".
The site of the first stone tool industry was found in the Olduvai Gorge.
Contemporary paleoanthropologists do not fully agree on who, among the hominin species
that contemporaneously lived around 2.5 millennia, first used these stone tools. According to
Boyd and Silk, the owner of the stone tools at Olduvai could have been one of many
australopithecines and their close relatives living at the same time. It could even have
belonged to Homo ergaster, which was left at the site with the bones of australopithesin1.
Although there is no agreement on who the first hominin to use tools was,
paleoanthropologists agree that hominins were already using tools.
Stone tools are found at many hominin discovery sites. The Koobi-Fora site in
Kenya and Olduvai in Tanzania, for example, contain not only fossilized hominin remains,
but also the bones of animals used as food. The sites also characterize a stone tool
manufacturing site as well as a butchery. While it is clear that the stone tools there were also
made there, the site is not at all characterized as a source of raw materials for the tools. This
means that the raw materials for making the tools seem to have existed elsewhere. In fact,
there are several sites about 3 to 4 kilometers away that are thought to be sources of stone
tools2.
More advanced tool use and making appeared first in the life of the oldest homo
species, Homo ergaster. They lived in the early Pleistocene (1.8 c.e. to 900 c.e.) when there
was a general cooling of the Earth's climate. Ergaster is also recorded as a hominin first to
come out of Africa. In 1991 their fossilized tools were found in the Caucasus Mountains of
Georgia with a calculated life span of between 1.8 to 1.1 millennia. Then in 1999 in Dmanisi
fossilized ergaster bones were found that were estimated to live at 1.7 millennia along with
about 1000 fossilized tools1. In addition to significant changes in body structure with a skull
capacity of more than 800 cc, ergasters are also known to use finer tools. Ergaster tools
belong to the 2nd mode Acheulean industry which is more advanced than 1st mode Olduvai
tools. This hand-held axe was most likely used to shred the flesh of large animals and it is
believed that ergaster ate meat although it is uncertain whether it was obtained from hunting
or scavenging carcasses.
In hominins of the genus homo, the use of tools was also accompanied by the ability
to use fire as a means of food processing. There is a small possibility that ergaster utilized
fire2. At some ergaster fossil sites, ashes and burnt bones have been found. However,
paleoanthropology scholars are not sure whether ergaster actively used fire or whether the
fire was left behind by natural causes such as forest fires, lightning, or others3 (Boyd and
Silk, 2003: 346). During the life of Homo erectus, the use of fire became more assertive.
Sinanthropus pekinensis, who lived in the Zhoukoudian cave near Beijing, probably utilized
fire, although most scholars are not sure whether it was productive or passive4. It is only in
Homo neanderthalensis that the productive (making) use of fire emerges clearly5.
Without further evidence, the use, manufacture of stone tools, the use of stone tools,
the use of stone tools, the use of stone tools, and the use of stone tools the use of fire, and
the consumption of large animal meat presupposes the existence of a fire certain forms of
cooperation and social division of labor. At the very least, there is stone collecting, sorting,
preparing, transporting, using, and re-sharpening tools. All these activities are hard to
imagine without cooperation and division of labor, or at least social behaviors. The
consumption of meat from large animals such as antelopes, pigs, horses, elephants, hippos,
rhinos, and so on1 is hard to imagine without cooperation in hunting or at least in
transporting and slaughtering them. Consumption of large animal meat is also hard to
imagine without the sharing of food2.
Cooperation and division of labor within hominin groups based on tool use is also
indicated by their anatomy. Already since the appearance of the homo genus, hominin pelvic
bones developed. The development of the pelvis was related to adaptations to the brain
expansion of the infant relative to the body that had to be conceived and delivered. The
enlargement of the size of the brain organ relative to the size of the body poses problems in
childbearing. Physiologically, this was solved by delaying the development of the child's
brain until after birth. The brain of hominin infants is not complete. Its elements are
incomplete at birth. The brains of homo infants are much less complete at birth than those of
other primates. For example, a chimpanzee baby's brain is 60% complete while a hominin
baby's is only 24%3. This means that compared to other primates, hominin infants take
longer to reach post-natal brain perfection. The longer period of brain refinement means that
hominin infants require a longer period of protection and nurturing to become independent.
In addition, pregnancy and breastfeeding are "time-consuming and energy-intensive
activities for primate females "4. Duration The period of refinement of the child's brain after
birth and the high energy cost of conceiving and giving birth would have been impossible to
imagine without the social mechanisms that provided protection and nurturing. The long
nurturing period and the social organization that supported it was also the only way to allow
time for hominin children to absorb all traditions, especially in introducing food sources and
work skills1.
Hominins of the genus homo, from ergaster to neanderthalensis not only show the
development of brain organ size relative to body size, but also confirm the existence of a
social organization of work in their lives.
Work, Brain and Language:
Engels, in Dialektik der Natur, asserts that:
"in step with the development of the hand came the development of the brain; [then] came
consciousness, first associated with the conditions of production of the separation of
practically useful results, and then, among those who were more highly developed and
evolved than before, the knowledge of the natural laws that governed their lives "2.
The development of the function and effective use of hands has opened up new
horizons of hominin interaction with the surrounding nature. Activities with the hands,
especially in meeting the needs of life, first required coordination as well as the development
of a system of coordination of all the sensory organs. Millions of years of experience led to
changes in the brain organs that control motor movements.
Engels' idea that terrestrial life, bipedalism, and tool use in hominins preceded the
development of the didu-supported by modern paleoanthropology. Washburn and Howell,
for example, assert that: "the large size of certain hominin brains developed relatively later
and that the brain appeared associated with new selective pressures after bipedalism and was
a consequence of tool use "1. Bipedalism and tool use generated new selective pressures.
These pressures then gradually changed the makeup and composition of the hominin brain
as a biological response to these pressures.
With the biological development of the brain as the coordinator of the dialectical
relationship between humans and nature through handwork as well as the utilization of tools
and fire as means of differentiation, the emergence of human language became possible. As
already pointed out in the previous section, the change in body structure for bipedal living
and the emergence of means of production (stone tools and fire) in hominin life have
enhanced cooperation between individuals. Engels emphasized that "the development of
work inevitably helps to bring the members of society closer together through the
multiplication of instances of mutual assistance, of joint activity, and through the obvious
advantages of this joint activity for each individual. In short, human beings are on their way
to the point when they have something to say to each other "2.
Work, or the use of tools as a means of production, is related to brain and language
development in two ways. First, work generates new selective pressures that encourage the
development of certain mental abilities. Second, work further requires an effective and more
complex communication system. This communication system not only requires the
development of the brain quantitatively (enlargement of brain size relative to the body), but
also qualitatively (changes in brain organization and composition).
Hominin brain size increased throughout the Pleistocene, between 2ts and 300,000
years ago1. Hominin brains began to increase significantly in size relative to their body size
at 2 AD with the appearance of Homo habilis (2.5-1.6 AD). Habilis had a brain size 50
percent larger than that of Australopithecus afarensis. The structure and composition of the
habilis brain also developed. One of the regions that developed was Borca; the brain organ
responsible for the movement of the muscles of the mouth, tongue, and throat that are
important for the development of human language2.
Some scientists believe that it was only during the time of ergaster or erectus that
communicative abilities close to human language emerged. Erectus not only had larger
brains than earlier hominins, but also used tools more intensively and their populations were
also geographically dispersed. Wynn argues that erectus' use of tools went hand in hand with
vocalizations and gestures related to the division of labor between individuals and their
division of time and work operations. This means that erectus already had skills that were
very close to modern human language. The brain structure of erectus also shows the
development of their Borca and Wernicke regions, albeit still primitive3.
Coqueugniot and colleagues do not believe human language had emerged by erectus.
In their analysis of fossilized erectus children from Java they concluded that "in H. Erectus
the refinement of the brain in the extra-maternal environment took only a short period of
time. This makes it unlikely that early homo had the same cognitive abilities as modern
humans, and it is It also has the effect that complex spoken language emerged relatively late
in the course of human evolution "1.
Investigations into the skull and brain structure of Homo neanderthalensis and
comparisons with other homo species suggest that it is only in their kind that a language
similar to modern human language may have emerged. At least the neurological
development of neanderthalensis provides physical evidence for the possibility of a
language similar to that of modern humans2.
Despite scholarly disagreement about which hominin species first developed
communicative abilities beyond those of their primate relatives, it is clear that the
development of the brain and (proto-)language came after millions of years of upright
standing, bipedalism, work, and tool production by hominins. This flow is in line with the
evolutionary flow proposed by Engels, who understood that hominins' growing habit of
using tools and the emergence of a distinction between production and consumption that
showed the important role of social labor in hominin life were prerequisites for the
development of brain organs and, subsequently, communication systems through language.
Paleoanthropologist Ben Marwick asserts that the differentiation of production and
consumption allowed primitive elements of human language to emerge. The existence of
specialized sites for raw materials, industry, and game processing that indicate the
movement of raw materials for tool making and food from one place to another gave rise to
new selective pressures3. The differentiation of consumption from production changed the
ability to communicate between hominin individuals, which enabled the emergence of
language at the next evolutionary stage. The increase in long-distance transportation habits
resulted from the ability to gather social and linguistic information environment using
protolanguage. The operation of this network of exchange requires communication skills
between individuals such as the use of symbols, the expression of distinctions of time and
space, the expression of the purposefulness of actions in a social context, and so on, or in
Engels' words, humans finally "have something to say to each other".
As the joint operation of the hand, speech organ and brain increases, "not only
individually but also within society, humans become capable of performing more complex
operations "1. Dialectically, the development of the brain and an effective communication
system led to further developments in man's ability to perceive the experiences of his
surroundings and its challenges and thus the horizons of man's view of his natural
environment. "Along with the development of the brain, the most important means [of
human and natural interaction] also develops-the sense organs. Just as the gradual
development of speech needs to be accompanied by the corresponding refinement of the
sense of hearing, so the development of the brain as a whole is accompanied by the
refinement of all the senses", says Engels2. The refinement of the sense of perception that is
intertwined with the refinement of the brain makes it possible again for man to perceive
things that are not perceived by other animals. Not only food sources, but also techniques
and tools and new forms of social organization opened up from the box of nature, ready for
man to use in his next evolutionary journey.
With increasingly effective tools, hominin energy intake became diverse and
together with tool work became something adaptive to the diversity of food sources and
geographies in which it lived.
Work and Human Symbolic Capacity:
In general, Engels was convinced that increased brain size was not a sign of hominin
advancement on the evolutionary ladder. The paleoanthropo- log generation of the 1970s
and 1980s were still convinced that brain size was a sign toward humans. When they
searched for human ancestors, the only factor they looked for was brain size. They once
rejected Miocene hominins as hominins on the grounds that their brain size was equal to or
even smaller than modern apes. For this reason, scholars at the time believed that Homo
habilis, which had a brain size of 500 cc, belonged to the genus homo. Paleoanthropologists
now agree that habilis is still in the australopithesin genus. If this brain capacity is
associated with symbolic capacity, then the theory of simultaneous evolution proposed by
Darwin and most scholars until the 1970s is wrong. If symbolic capacity is evidenced by the
production of symbols, then in the history of humans on earth that evidence has only
appeared 40 rts. A long way from the time of the first evolution of bipedalism and the
development of the distinctive human hand. Hominin brain capacity was produced by
"anatomical and historical differentiation" since the first human ancestors lived on the
ground 7-6 millennia ago.
If brain size characterizes hominin humanity, then Homo Neanderthalensis was more
human than modern humans because it had a larger brain size. The belief that brain size is
not the most important factor in hominin evolution is also supported by the recent discovery
of Homo floresiensis fossils. Their brain size was not much larger than that of higher apes
and australopithecines, at around 380-410 cc. Their brain size and height were close to those
of australo- pithecus, but scholars believe they belonged to the genus homo, even on a
ladder that places them contemporaneous with Homo sapiens, who lived between 100-12
rts1.
According to contemporary paleoanthropologists, there are no structures in the
human brain that are not also found in the brains of higher primates. Human brain cells are
also not unique. There are no new cells or cell connections in the human brain compared to
the brains of higher apes1. This opinion is supported by Ian Tattersall's conclusion.
According to Tattersall, it is not the physiological development of the brain that is
responsible for the emergence of symbolic thinking in Homo sapiens, but something
cultural2. This supports Engels' idea that work (cultural activity) in hominins gave rise to
new selective pressures when faced with environmental changes, both due to changes in the
earth's climate and due to the geographical dispersal of hominins to different climatic
environments. The natural challenges of hominin dispersal gave rise to new fields of activity
that "had" to be addressed by labor. The area of work expenditure increased quantitatively,
and this affected the performance of the brain as the coordinator of motor activity. The
quantitative increase in the area of work, at a later stage, changes the organization of work
and the development of the brain. As a means of coordinating the senses that drive and are
driven by active engagement with nature, the brain eventually undergoes qualitative changes
that enable the emergence of reflective consciousness and symbolic abilities that are the
basis for the emergence and development of religion, art, and all other superstructural
institutions in Homo sapiens. In the words of biologist Philiph Lieberman, "a gradual
process of anatomical change at some point reaches a sudden functional advantage that will
lead to qualitatively different patterns of behavior in the species "3.
Cover:
From the exposition throughout this paper, it can be concluded that in Engels' theory,
the flow of human evolution from the world of apes was not preceded by the development of
brain size and cognitive abilities. Brain size and cognitive abilities are not the cause, but the
result, of the various biological and social developments and differentiations of hominin
evolution. The evolutionary path to man has gone through various differentiations. These
steps, in Engels' conception, are:
1.
Habitat shifts from arboreal to terrestrial in the context of changes in the natural
environment to which early hominins responded. This change is seen in late Miocene
(7-5 AD) and early Pliocene (5-3 AD) hominins.
2.
The differentiation of hand functions from feet was a prerequisite for upright standing,
bipedalism, tool use and labor. These changes began to appear in australopithecines and
their cousins living in the Pliocene and developed more efficiently in the genus homo in
the Pleistocene (from 2.5 AD).
3.
Differentiation of work tools from body organs. This differentiation allowed the
differentiation of consumption from production and showed the development of work
and cooperation as a typical hominin lifestyle. This feature only appears in the genus
homo.
4.
The geographical differentiation of places of life accompanied by the development of
brain organs and social organization as the basis for the emergence of language. This
feature was only apparent in Homo ergaster and Homo erectus and was further
developed in subsequent homo species.
5.
Further developments in human symbolic abilities, including rational thinking, laid the
foundation for the emergence of superstructural institutions that only appeared in the
last hominin, Homo sapiens.
Engels' contribution to the understanding of hominin evolution was his recognition
of the importance of work in the evolution towards humanity. In the theoretical framework
proposed by anthropologist Eugene Ruyle1, the thermodynamics of the relationship between
humans and nature consists of two streams, namely bioenergy and socioenergy. Bioenergy
includes sources of energy intake for the population such as sunlight, plants, game, and so
on. Socioenergy includes the activities of the population in taking, managing and consuming
energy. Work, in Engels' understanding, is the socioenergy through which hominin
populations interact with nature (including natural aspects such as the body). Together with
social interactions between individuals, work becomes a means of actively taking in and
consuming energy. It is called "socioenergy" because in homi- nin, energy management and
utilization are never separated from actions within the framework of communal life. In
contrast to other forms of ethnoenergy: play, leisure, sex, and so on, work is the motor of
change and development of the population's energy intake and expenditure. The
effectiveness of work not only has a bearing on the reproduction of the population, but also
on its growth, both quantitatively and qualitatively.
As socioenergy, work is not just a technical intermediary of relationships humans
and nature in managing energy acquisition and expenditure. Work is an existential process
without which hominins might not have evolved successfully. Work not only changes
nature, but also changes hominins themselves at the same time. The nature of the
relationship between hominins and nature through work as Engels believed is not
mechanical as in the sociobiological view. Nor is it unidirectional as in the view of the
mechanical materialists. Nor is it something transcendent beyond nature as the idealists
believed. Work is in the dialectic between nature and hominin as one. Any change in the
way hominins Extracting and utilizing energy from nature has always been accompanied by
changes in hominin life itself, including the way it views nature and itself. Once work
became the way humans related to nature, a wide range of possible developments emerged.
That is why the evolution of humans ran far behind that of their ape cousins. While apes and
other animals rely on biologically inherited behaviors and mutations in their adaptation to
nature, humans rely on cultural mutations through work as an existential element. The use of
tools and the outpouring of labor as a form of active interaction with nature led to a
widening of the horizons of action and forms of organization of activities that led to the
development of the brain and language.
Leslie G. Freeman, an American paleoanthropologist, in his book Anthropology
without Informants, states: "from the materialist point of view that is important to
paleoanthropologists, cultural systems are complexes of socially - rather than biologically -
derived patterns of behavior by which some organisms bridge their relationships with their
surroundings, including with other organisms. "1 Freeman's definition of culture fits with
how Engels understood the difference between humans and other animals. For Engels,
humans differ from other animals primarily because of their ability to solve problems
through work and social actions. Humans are problem-solving animals. The first problem
they solve is the most fundamental problem for life, which is securing the survival of the
species as a biological life. Therefore, Engels also saw man as a product of the natural
world, and human evolution as part of natural evolution. However, Engels also emphasized
the special characteristics of human beings in responding to environmental changes that had
occurred in the past both create them and they create them, thus changing nature and
themselves. It is all in a dialectical relationship.
For Engels himself, investigating human origins was not just a scientific matter in order to
understand human social organization and culture. Explaining the origin and course of
human evolution was closely linked to his political views. The questions of what are the
fundamental features that distinguish and separate humans from other animals and what is
the significance of understanding these differences in understanding existing societies and
cultures are closely linked to the question: "How should we organize life together among
members of society and between humans and nature?".
