THE MAIN DRIVING
FORCES AND STAGES OF HUMAN BECOMING AN INTELLIGENT BEING
Humans became intelligent beings through three leaps
resulting from the influence of three main driving forces.
Three Main Driving
Forces
1. Variations (genetic diversity)
2. Natural selection pressure
3. The skeletal transformation triggered by standing upright
seven million years ago, continuing throughout all hominin stages and still
ongoing today
Three Leaps
1. The leap to bipedalism that occurred seven million years
ago
2. The intelligence somersault leap that occurred around two
million years ago
3. The intelligence-threshold leap, in which humans reached
the mental capacity to create tools by attaching a stone to a stick—a type of
object never before produced by nature under natural conditions
The Three Main Driving Forces and Their Functions
1. Variations
Evolutionary scientists say that if natural selection is the
engine of evolution, then variations are its raw material. Every newborn
organism is a variation. In other words, no two organisms on Earth have
identical genomes.
Every individual within a primate (chimpanzee) population
forced to stand on two feet is a variation. Some of these variations possess
genomes more suited to bipedalism, or such genomes will emerge in later generations.
If individuals with genomes predisposed to bipedalism do not arise within this
population, then the population cannot survive as a bipedal species, and no
bipedal primate speciation can occur.
2. Natural Selection Pressure
The main mechanism of general evolution—that is,
speciation—is natural selection pressure. Natural selection consists of the
pressures exerted by geographic location, climate conditions, diseases,
predators, food varieties and methods of obtaining them, and population security.
Collectively, these can be called habitat pressures.
Variations and natural selection pressure are the mechanisms
of general evolution. These two parameters account for the evolution and
speciation of all living organisms other than humans. Human evolution and the
emergence of the human species cannot be explained solely by these two driving
forces.
3. The Skeletal
Transformation Triggered by Standing Upright Seven Million Years Ago,
Continuing Through All Hominin Stages and Still Ongoing Today
Humans are the only mammalian species on Earth that is both
bipedal and vertically bodied. This third driving force is the determining
parameter in humanity’s becoming an intelligent species. The mechanisms and
processes of human evolution have not been adequately explained because this
reality—the skeletal transformation that began seven million years ago and
continues today—has not been recognized.
There are many hypotheses concerning human evolution, but
these hypotheses are often mutually exclusive and far from convincing. Skeletal
transformation has progressed from the toes to the leg bones, pelvis, rib cage,
arm lengths, finger bones, and, for the last two million years (after the
intelligence somersault), facial reduction and skull (brain) enlargement.
The Three Leaps
Produced by the Influence of These Driving Forces
1. The Leap to Bipedalism Seven Million Years Ago
Since I have discussed this in detail in many previous
articles, I will summarize it briefly here. Human bipedalism has traditionally
been attributed to prolonged and widespread life in the savanna. However, this
hypothesis has now largely been abandoned.
My proposal is that a primate population became trapped
somewhere in the Rift Valley due to natural events and environmental changes
and was forced to search for and obtain food in wetland environments. The fact
that hominin fossils are predominantly found in dried lake and river deposits,
and that carbon isotope analyses of fossil tooth enamel indicate a diet rich in
aquatic resources, can be cited as evidence supporting the hypothesis that
upright posture originated in wetlands.
2. The Intelligence Somersault
Leap Around Two Million Years Ago
Once bipedalism became necessary seven million years ago,
gradual torso straightening began over a very long period (approximately five
million years). The driving force behind this straightening was the necessity
of keeping the body's center of gravity within the area of the feet. Otherwise,
a creature unable to locomote optimally could not sustain its life or species.
Indeed, fossil skeletons from every stage of the last seven
million years show this gradual change toward the modern condition.
Around two million years ago, after five million years of
accumulated quantitative torso straightening, the embryo in the womb produced
an adaptive response to this vertical body structure. Everything that occurred
followed the laws of physics. The embryos of all horizontally bodied mammals
develop and are born facing the mother’s abdomen, with their heads toward the
birth canal and with limited freedom of movement.
The human embryo, however, had to orient its head toward the
mother's diaphragm. As a result, it was forced to bear the weight of the
mother's internal organs upon its skull. This led to enlargement and rounding
of the skull. It was this necessity of bearing weight that triggered skull
growth and consequently brain growth.
This proposal could theoretically be tested by implanting a
chimpanzee embryo into the womb of a modern human female whose body has fully
acquired vertical posture through seven million years of torso straightening.
Pure chimpanzees born from human wombs could then be bred with one another for
10–15 generations, with all gestation and births occurring in human wombs. The
results might surprise everyone. One might encounter a hairy chimpanzee with a
smaller face and a larger skull saying “good morning” to you.
An objection is often raised that such an experiment cannot
be performed for ethical reasons. However, the inability to conduct the
experiment does not falsify the hypothesis.
At the Homo habilis stage around two million years ago, a
sudden increase in brain size is observed (from 350 cc to 700 cc). For this
reason, I argue that the intelligence somersault occurred around two million
years ago.
3. The Intelligence-Threshold Leap: Reaching the Mental Capacity to
Create Tools Such as a Stone Attached to a Stick
The intelligence-threshold leap occurred when the brain
growth initiated by the intelligence somersault reached a certain size,
enabling the mental capacity to create tools not naturally found in nature.
The ancestor of the spacecraft that carried modern humans
(the Homo sapiens stage) to the Moon was that first stone attached to a stick.
Beginning with *Sahelanthropus tchadensis*, which stood
upright seven million years ago, the skeletal transformation within hominins
has continued in the same form and at the same rate regardless of the habitat
in which they lived or the geographic adaptations they underwent. The primary
cause of differences in appearance among hominins is skeletal transformation.
Geographic adaptations also contribute to these differences, though they are
not the determining factor.
All hominins have undergone the same skeletal transformation
at the same rate, speed, and manner. Once hominins reached a certain level of
mental capacity, they began moving into different parts of the world. This
mental capacity gave them the ability to imagine what lay beyond a mountain—in
a sense, to “see” beyond it. Animals live according to what they see or
perceive through their senses, whereas hominins additionally possess imagination.
Throughout the seven-million-year process of bipedalism,
hominins exchanged genes both horizontally and vertically, assimilated one
another, and ultimately reached the final hominin stage, *Homo sapiens
sapiens*.
In recent years, genetic sequences obtained from
approximately 40,000-year-old fossils have demonstrated that Neanderthals,
Denisovans, *Homo floresiensis*, and *Homo sapiens* exchanged genes
horizontally—that is, they interbred. Likewise, Chinese scientists have
recently demonstrated vertical gene transfer using sequenced proteins obtained
from 400,000-year-old *Homo erectus* fossil teeth. Vertical gene transfer means
that genes acquired from *Homo erectus* by Denisovans through interbreeding
400,000 years ago were carried forward through generations and transmitted to
the present.
Considering all this, it should be assumed that mechanisms
of horizontal and vertical gene transfer operated throughout the hominin
period. In other words, hominins were not separate species but rather a single
species exhibiting minor phenotypic differences resulting from accumulated
quantitative skeletal changes and geographic adaptations. Every hominin shared
a common skeletal structure that changed simultaneously and in parallel.
The skeletal transformation triggered by standing upright
seven million years ago has continued until today and is still ongoing. This
transformation produces accumulations of quantitative skeletal changes over
long periods. These accumulations of quantitative change lead to qualitative
leaps and transformations. As a result of these quantitative accumulations and
qualitative transformations (leaps), hominins with only slight phenotypic
differences emerge.
In other words, after *Sahelanthropus tchadensis*,
accumulated quantitative skeletal changes produced a qualitative transformation
that gave rise to *Orrorin tugenensis*. The accumulated quantitative skeletal
changes in *Orrorin tugenensis* then produced a qualitative transformation
resulting in *Ardipithecus ramidus*. The accumulated quantitative skeletal
changes in *Ardipithecus ramidus* produced a qualitative transformation
resulting in the australopithecines, and so on. This mechanism continued
throughout all hominin stages.
According to research, these accumulations of quantitative
skeletal changes, which continue even today, are still operating in *Homo
sapiens* and are transforming it toward another hominin form.
In conclusion, hominins are not separate species. Rather,
they are the same species exhibiting phenotypic differences caused primarily by
skeletal transformations that have continued for seven million years, together
with geographic adaptations.