THREE LEAPS IN HUMAN EVOLUTION
Oktay Kaynak
Independent Researcher
Turkey
oktaykaynak@hotmail.com
Bipedalism:
6-7mya as a result of Rift and plateau formation in east Africa, a primate made an adaptive response to that formation. This adaptive response was hunting and gathering food in shallow waters on two legs. This shallow water made a selective pressure on that primate to walk bipedally.
Mental Overturning:
When about 2mya the body erection reached a certain angle, the embryo made an adaptive response to this vertical body posture. The embryo turned upside down. This is the mental overturning that started the growth of the cranium as well as the brain.
Mental Threshold:
After chasing its enemy, the chimp throws the stick and stones. It does not say to itself: ''This stick and stone have served me effectively; I better keep them for another occasion''. But there will be a time and a brain capacity(500-550cc) that such a thought will occur.
Key Words: human evolution, mental overturning, mental threshold, anthropology
INTRODUCTION
Initially the science of Anthropology has intuitively linked the bipedalism of the human species to its intellectual capacity. As the fossils and bones of the Australopithecine started to appear, subsequent work and research continued to support the initial intuitive assumption. The mechanism of evolution for all species can be explained as follows: Small changes in the environment and habitat create selective pressures on the organism, and the organism gives adaptive response to them. As these changes accumulate over a long period of time, speciation happens. This is how science explains the process of evolution. But such an explanation, regarding the evolution of human did not, until now, give satisfactory results.
For the following reasons:
Human are different when compared to other species on earth. But the same process of evolution has been assumed to apply for both human and other species. Accordingly, the human lineage separated from a common ancestor about 6mya, and the mechanisms of natural selection resulted in forming the modern human.
Human are very special and very different. These are the only living being on earth endeavoring in self investigation. Then one can ask if the evolution processes regarding human are specific to this species only, or not. My answer is “yes”. This species had to experience three consecutive and important leaps before becoming modern human.
1- The Leap of Bipedalism
Being bipedal and growth of brain are two fundamental facts in human evolution. For many years, researchers put forward various theses on how these two changes in human evolution have taken place. Theoretical discussions aimed at finding answers for basic questions have highly significant influence in the development of a science. The subject of this article is the causes of being bipedal and brain grow in human evolution. I will comment, in ecological viewpoint, on how being bipedal come forward in human evolution and I will try to disclose growth of human brain in a completely new perspective and through a hypothesis based on embryonic development. My aim is to clear the way by my new perspective for the discussions in the world of paleoanthropology on these subjects.
It is widely known that water was permanently existed in the Rift Valley that has formed in Africa 8-10mya. The reasons of the conclusion that water permanently existed there are the existence of dried lake bottom sediments now and redundancy of fresh water lakes in the region. Carbonated lakes, called “Green Sea” by local population, in gigantic dimensions such as Victoria and Turcana lies nearly throughout the Rift Valley. The main reason of this formation is tectonics separation zones resulted in Rift depression. And tectonic separation zones caused the formation of many volcanoes, underground waters came up earth’s surface, lava and volcano ashes fallen upon the existing equatorial forests. These changes resulted in forest fires. The same tectonic movements caused great earthquakes. These forest fires have to be associated with non-existence of equatorial forests to the east of East African wall. Volcanic movements of important dimensions, flood of hot and cold underground waters, earthquakes and forest fires have changed the environment ecologically and feeding conditions. That our predecessor arboreal primate has survived somehow perhaps in a very specific and small area has to be taken into consideration. The life is processes in which problems such as feed, shelter, reproduction and defence against predators are being solved. The life can be maintained through solving these four problems. The life and generation can be maintained only through these four problems that have arisen in new conditions. Otherwise the life and generation cannot be maintained and the species disappear. Our predecessor primate maintained an arboreal life for a time in a small area somewhere that was not affected by the fire and tried to solve feeding problem with ending of eatable fruit, leaf, branch and peel on trees. It has to be taken into consideration that primates tried to solve the feeding problem in water after volcano ashes covered and burned the surface of terrestrial area. It may be said that primates easily solved feeding problem in waters when one give thought to the long-time water existence at Rift Valley. Primates fed on aquatic plant products walking in the water in upright position and keeping the head over the surface of the water for breathing and spent the nights on semi blasted wood trunks, on a small piece of land or on some other higher places. Most probably the primates at the time met with various aquatic products, crustaceans and the fish. Long tailed Macaques living today along the Ketanbe River to the north of Sumatra Province of Borneo Island of Indonesia can fish barehanded and this is the evidence of the suggestion that they tried to solve their feeding problem in water. This fact was observed by an organization called Nature Conservancy and The Great Ape Trust and has been published.
Primates lived for 4-5my. as semiarboreal –semiaquatic living. Yet, the terms semiarboreal – semiaquatic does not mean that they were amphibious. It may be deducted from these terms that primates spent the nights on lands or at trees, in daytime erecting on two legs in shallow waters foraging or hunting as much aquatic products as possible. That an aquatic period exists in the evolution process of human is advocated particularly by Wood Jones and Sir Alister Hardy. Marine zoologist Hardy finds similarities between human and whale and dolphin in nakedness and existence of subcutaneous fat tissues. And aquatic mammals such as sea cow (sirenia) and eared seal (otariidae) resembles human due to their same characteristics. Namely they are either hairless and their subcutaneous fat tissues are attached to their dermis when they are being skinned. This is the same for human. Subcutaneous fat tissues of human, comes out as attached to the dermis when a human is being skinned. But when land animals skinned subcutaneous fat tissues continues to be attached to the muscular tissues and they do not come out on skinned dermis. Nevertheless this suggestion is not accepted because a clear knowledge about primate aquatic life does not exist. And descriptions about the aquatic life of primates are incorrect because it likened to the life forms of penguins and dolphins. After all, if primates would have solved the feeding problem through swimming or diving as dolphins or penguins they should have had web formation between their toes. Hardy alleges that the head of primate is hairy and body is naked because primates keep the head above the surface of the water when swimming. And I, say that our predecessor primate have solved feeding problem through WALKING in the shallow water but not through SWIMMING and DIVING. My opinion is that the head of primate is hairy due to keeping the head above surface of the water, the body is hairless due to body is in the water surface when hunting.
The evidences of my suggestion are below:
1. 1-Rift Valley is full of both lake sediments and lake bottom sediments
- Australopithecus afarensis suffered rheumatoid arthritis
- The argument that Australopithecus afarensis family of 13 members have suffocated in water
- Our body is hairless and our head is hairy (due to keeping above the surface). Darwin stresses in his The Origin of Species that the thesis put forward by a researcher named Mr. Belt that we limed our hair in order to recover our parasites is wrong because, Darwin continues, many four footed living in tropical countries did not react to the same factor as others did. On the other hand, says Darwin, if we suppose that the thesis that we limed our hair in order to adjust our body temperature to the conditions of tropical region, we cannot explain our hairy head in spite of its permanent openness to the sun beam and this a paradox. Keeping body in the water and head above the surface of the water due to the necessity of breathing can explain the hairless body and hairy head.
- Most of the Australopithecine fossils have found at old dried lake or river sides together with fossils of shallow and deep water living beings such as Hippopotamus and Diatoms. Additionally, that the fossils of the remnants of equatorial forests in the same aged sediments with the same fossils have been found shows us that our predecessor primate lived in equatorial forests. All living beings produced solutions in order to keep the body temperature between certain degrees. These solutions are generally hair and subcutaneous fat tissues. It is widely known that the animals moved from land to the sea such as dolphins and whales replaced the hair they lost with subcutaneous fat tissues in order to balance their body temperature (Mayr,2008). Our subcutaneous fat tissues are the consequence of our life spent in the water for 4-5my.
- Laetoli foot prints found in Tanzania are the foot prints of two Australopithecus walking side by side. Johanson argues that these foot prints are of two Australopithecus walking side by side on the ash layer cooled and softened by the rain water which has fallen on ash layer formed after a volcano fenced out ashes. In my opinion, the lava had to be fresh and cooled for the formation of these foot prints. And this can be happen with water. The argument that these foot prints are on a volcanic material that had fallen on the lake recently has to be taken into account. On the other hand, erecting in water hypothesis told above can be tested:
Let us generate an artificial lake. The dimensions of the lake are sufficient for a chimp colony to easily live in it. The depth of the lake is as deep as forcing the chimp family to erect position, namely, 70-120cm. Shady spots and wood trunks exist on the sides of the lake. Yet, nothing can be found to eat on these wood trunks by chimps. And the material on these shady spots is inorganic and uneatable by the chimps. The lake has to be generated in a tropical area (like Rift Valley) so that chimps can easily live there in winters. The floats put in the lake carries fruits such as banana which are chimp favourites. The fruits are put on proper points that can be easily seen by the chimps. Their favourite fruits will force the chimps to erect on their hind feet and walk towards them. Later, raise frog, crab and fish in the lake and after determining their favourite fish facilitate the meeting between chimps and fishes. If this experiment continues for four or five generations we will observe that the chimps are erected in order to be fed by aquatic products, to survive and reproduce. Additionally, we will observe that the chimps solve their feeding problem keeping their body in the water and their heads above the surface of the water and the beginning of hairlessness on their bodies. (Kaynak2007, 2010, 2011, 2013a, 2015, 2017a, 2017b). The opponents of the thesis of Hardy and others agree with his thesis alleged that the thesis cannot be tested. Yet, I insist that this thesis can be tested and I propose an experiment. Today, a discussion continues on whether the cause of a new species is mutational or recombinational changes in the genetic inheritance or environmental changes. Mechanism of natural selection operates as such.
When the conditions change in a living space of a species that do not allow for it to survive, the variations in the genetic inheritance of the same species that provide adaptation to the new conditions are selected. In other words, individuals among the newborn which carries the positive mutational or recombinational genetic changes that make the adaptation of the species possible to the new conditions are being selected. When new born which carries these inheritable genetic changes do not exist the species in question cannot adapt itself to the new conditions and consequently disappear. The adaptation of a certain species to the new conditions needs two factors. First, the existence of mutational or recombinational inheritable genetic changes proper to the new conditions is necessary for the survival of the species. Second, the natural selection mechanism must operate in way that it selects the proper individuals. A species suitable to the new conditions appears in such a mechanism. Differentiation and separation of our genetic arrays dated 6 -6.5my. back. Barely, it is not easy naturally to calculate how many millions years had to pass in upright position before the bone form change have, become permanent. Upper body forced to become hominid after the lover body became hominid in 4-5my. Upper body compelled to become hominid because only a double carrier skeleton system (same as today’s human) can allow the living being to survive. The centre of gravity of carrier skeleton must be in the soles. The body has to become upright posture, the rib become cylindrical the head must be placed over the body like human of today in order to provide the necessary place for the gravity centre.
2- The Leap of Mental Overturning
Upper body started becoming gradually erected to this end. This upright position and the angle of vertebra femur cannot be discerned in Australopithecus fossils because this angle is destroyed during the fossilization process. And we are two footed for 4-5my. Here the question comes, although we are walking on our two feet why our brains do not grow? This question is being put because the pelvis structure on Australopithecus fossils is ignored. Yet, the pelvis of Australopithecus is at somewhere within in the range of evolution between the pelvis of contemporary human and pelvis of primate. This is because the upper body does not step precisely on the pelvis. Australopithecus’s all bones, from the toe to the ilium bone of the pelvis, resemble contemporary human except the angle of vertebra’s pressing on pelvis and ilium bone of pelvis. Australopithecus’s upper body, vertebra’s structure, skull and the shape of jaw are like primate. In other words, the process of resemblance started with the toe and ended with the jaw and skull. This process started with toe. Scientists have taken this resemblance into consideration and intuitionally found relation between upright position and intelligent living being. Everything started with erect position and everything started with toe.
The position of embryo in the uterus has changed at a certain phase of gradually erecting process of the body. The embryo Australopithecus turned its head towards diaphragm and its body came close to the birth canal after turning a 180° somersault in uterus. Without this somersault, which I call MENTAL OVERTURNING, Australopithecus would have kept its head as turned towards the birth canal. After this mental overturning each prospective mother Australopithecus started to give birth to offspring of which the volume of skull is larger than her. In other words, the offspring’s skull volume is larger than the mother’s. Australopithecus’s growing skull is being observed on the fossils while the other changes cannot be. Because gradual process of body’s erecting, rib’s narrowing and growing cylindrical cannot be discerned.(Kaynak2007, 2011, 2012b, 2013c, 2015 2017b) Different skulls of Australopithecus led some to conclude that there are different Australopithecus species. However, these are not different species. They are Australopithecus generated through body erection and rib narrowing. The most important result of the mental overturning is that offspring started to be born with the face towards one of the legs of the mother (Trevathan,1987). Yet, after the completion of the body erection, offspring started to be born with the face towards back of the mother that is a characteristic of contemporary human. This fact is peculiar to human being. All the other mammals are born as their face turned to the abdomen of the mother. The cause of this important difference is mental overturning. This weakness that starts with birth forces the offspring to semiterrestrial life. The offspring primates cling to the hair of their mothers just after birth. The origins of the fact that human child grasps whatever they are hold out as a reflex have to be connected with the fact that the child of the primate cling to the hair of the mother as a reflex. The child of a primate has to cling to the hair of the mother because she has born on a three and otherwise would fall down and die. 400-450-500….750-800cc skull volumes has been found on the anthropoid fossils. Skull volume starts to correspond to the body erection angle, after body erection process begins and the volume continues to change till the angle of vertebra femur reaches to 180°. One has to pay attention to the fact that the skull volume determines the quantity of brain tissue.
The hands of primate, the predecessor of human, become free with the erect position could produce tools. Consequently, primate is being regarded as intelligent living being. A coordination exist between the front and rear extremities of contemporary chimps. Their hands are free and they use their hands but they are not intelligent living beings. According to another thesis, they are intelligent living beings because they became social after erecting on two feet and can be face to face and developed speaking (Mayr2008). Yet, Darwin stressed that some other living beings can be face to face and had various organs which are able to produce necessary voices for speaking but they cannot speak. Because, for Darwin, the skill has to be developed in order to produce speaking. (Darwin1996,2002)
Human embryo skull develops, takes shape and form in conformity with internal and external vectorial forces that influence on the skull.
These forces may be explained as such:
1-External forces: the gravity, pressure of uterus and amniotic sac, the pressure of abdomen muscles of the mother, the pressure of diaphragm and innards of the mother,
2- Internal forces: the gravity, the resistance of the intra cranial fluids and brain tissues coming into existence.
Today science suggests that human embryo skull develops, takes shape and form in conformity with these vectorial, internal and external forces. Human embryo skull’s development and coming into existence doesn’t take place as a coil sprung (Blechschmidt 1969,1971). My opinion is that the impetus and direction of these vectorial forces have changed as the body gradually erecting. Consequently Australopithecus’s skull volume corresponds to different phases of body perpendicularity angle during the process of becoming erected (Kaynak,1983, 2007, 2010, 2011, 2012a, 2013c, 2017b). The growth of skull volume continued till body’s becoming erected position processes have drowned to an end. The changes observed on the skull form of the child taken out during birth by forceps or by vacuum technique. New born rats’ and rabbits’ one sided cervical muscles and /or chewing muscles or both cervical muscles and chewing muscles cut out for an experiment. The observations are such: While non operated half of the skull of these experiment animals developed normally and specific to the species, in the part of the next skull from which the cervical and chewing muscles cut out the metacarpus is not developed, namely, this part of the skull, in a way, developed in a different form.
%70 of the adult human body is water, more than %90 of the embryo in the uterus is water. The bones can be warped. The bones stretches and they do not be broken. When a pressure exerted in one direction from any angle on the skull of an embryo of four or five months, the skull is expected to be deformed in conformity with the direction of the pressure. Since deformations are not observed on the skull in the uterus it is understood that the embryo is packaged and bundled by the uterus. Human nestling cannot keep her head over the body even just after birth. Yet, thanks to this packaging of the uterus, the embryo can keep the head exactly over the body. When the embryo is of seven months and turn upside down for preparation to the birth, the body, in turn, in a similar way, is being carried and kept over the head. It is this mechanism that causes the human skull’s becoming round, jaw’s becoming small, eyebrow arch’s straightening and growth of skull volume. Human embryo is born without synostosis. The only new born with holes called fonticulus is human. That means human bone and tissue development cannot respond to the human embryo skull development and the growth of the skull process is faster than tissue formation. Similarly, human uterus cannot enlarge and consequently birth contractions stars. In other words, the embryo is born without completing its development. This fact can be observed only in the human uterus and human embryo. All the other mammals are born as completed synostosis, without fonticulus, in a development phase which allows surviving in and resisting against the nature. And basically it must be in this way.
Because, of the fact that the form of the rib transformed from the conical to cylindrical. Consequently abdomen region has narrowed. Human nestling is being put out without completing its development due to this space insufficiency.
We can conclude, as a result all of these, that human uterus is unique among all mammals and produces a unique living being because of its own uniqueness.
Great jaw, protuberant eyebrow arch accompany to small skull at Australopithecus. In other words either great skull or great jaw and protuberant eyebrow arc exist. Both of them cannot be seen on Australopithecus. We, at this point, come to the conclusion that gradually diminishing jaw, straightening eyebrow arch replace with great skull. This result is being produced by the uterus, which gradually adapt itself to the body that is becoming erected. Why the jaw diminishes and the skull grows simultaneously or in parallel with each other? On the other hand could the skull grow when the jaw keeps its greatness? No, the skull would have not be able to grow when the jaw continue to be great. Because this change is generated by uterus, human uterus is as much strained as not to cause the embryo to be run over but to give it a shape it wants to be. Human uterus pushes the embryo backward through pushing on incisors which we see at the extreme point of the primate skull. The nose and chin area come into existence as the result of this pushing backward. This front mandibular projection makes no vital contribution at human species. These are the results of the packaging of uterus. The evolution process does not develop body organs which it does not use in natural circumstances. The evolution, at the most, keeps caducous organs that are left by the predecessor of a certain species. This front mandibular projection do, not exist in any primate. It comes into being through uterus’s push on incisors so that the embryo moves backward.
All the ideas I have put forward here can be tested by an experiment:
We will implant a chimp embryo into a human uterus. We can administer the development of this embryo in human uterus through medicines and medical techniques. One of these techniques is such: take up the cells (specialized for forming the placenta) that are lined up in single file on human zygote of 4-5days. And the cells producing the placenta out of the chimp zygote are burgled and thrown away. The cells that will generate the chimp in it are taken up and put into the cells that will produce the placenta taken up from the human. When this produced mixed zygote implanted into human uterus the transplant rejection is prevented. For this placenta will be a human placenta. When the birth realized in these conditions the nestling’s body will be hairy, hands and feet again like chimp but only the head is rounded and the volume of the head is greater. Among other things, the nose and front mandibular projection will come up and the jaw will become smaller. The pressure made by human uterus from front will transform the jaw shape from U to V shape. Now, the living species we have acquired is Australopithecus. Both the uterus and the embryo in it have been in their evolution process 4-5 million years ago. More and more growth at the skull’s volume has to be expected. For the available uterus has taken its final shape. We will not acquire a skull in an amazing greatness but bigger than chimp’s skull (350cc) in all conditions. (Kaynak1983, 2007, 2010, 2011, 2015, 2017a)
Additionally, chimp’s embryo will complete its development in the human uterus as the head above the body for seven months and in the last two months, turning upside down, the body above the head, the way human newborn does. Chimp newborn will be born as the face not turned to the mother’s abdomen but similar to human newborn, with the face towards mother’s back. Most probably it will born as skull bones without synostosis, in other words with fonticulus, like human newborn.
3- The Leap of Mental Threshold
The present day chimp, with its 350cc brain can tear away a tree branch and attack its enemies with it. It can also pick up a stone and throw it to its enemy. When the predator cheetah approaches Capuchin monkeys of the Brazilian forests, they climb the cliffs and roll down an avalanche of rocks and stones, forcing the cheetah to retreat. These capuchin monkeys can also make use of stones in a sophisticated manner in order to break coconuts. The chimps can also make use of a stone for cracking fruit seeds.
In a way, both primates use the stone as a tool as well as a weapon. Chimps make use of thin twigs for hunting termites and collect honey from beehives. If a chimp with its 350cc brain can do such things, one should wonder what its capabilities would be, if it had a 500cc brain.
After chasing its enemy, the chimp throws the stick and does not say to itself: “This stick has served me effectively; I’d better keep it for another occasion”. If the chimp had a brain of 500cc, would it say: “I better keep this stick and even improve it”. The chimp may not think so with 500cc brain, not even with a 550cc or even a 600cc brain. But there will be a time and a brain capacity that such a thought will occur.
This is the critical point which I have labeled as the Mental Threshold. Once this mental threshold was transcended, the hominid that held a stone in one hand and a stick in the other; had the courage to intrude into the hunting zone of any animal including the worst predator.
When it reached the capacity to influence his prey as well as his predator from a distance with the help of sticks and stones, the hominid departed from the rift in order to colonize the world. After the mental threshold happened the hominid became cognizant of his nakedness, realized his selfness and came to understand that sticks and stones could be used as weapons.
The human mind is the result of the incredible adaptive responds given by the embryo to the vertical body posture.
References:
Blechschmidt, E.(1969) , Differenzierungen im Kinetischen Feld Paraitra dans
Blechschmidt, E.(1971) , Die ersten 3 Wochen nach der Befruchtung.
Darwin, C.(1996) Türlerin Kökeni (The Origin of Species)
Darwin, C.(2002) İnsanın Türeyişi (The Descent of Man)
Kaynak, O.(1983) ''Bir Memeli Embriyonu Diğer Bir Tür Memelinin Rahmine Yerleştirilip Büyütülürse Nasıl Bir Sonuç Alınır?'' Evcil Dergisi
Kaynak, O.(2007) ''Bugünkü Halimize Nasıl Dönüştük?'' Cumhuriyet Bilim ve Teknoloji Dergisi
Kaynak, O.(2010)'' İnsan Evriminde Dik Duruşun ve Beyin Büyümesinin Nasıl Gerçekleştiğine Dair Yeni Bir Hipotez '' IV. Ulusal Biyolojik Antropoloji Sempozyumu Bildiri Özetleri Kitapçığı s:2
Kaynak, O.(2011)''Australopithecus Sediba'nın ''Akıl Taklası Bakış Açısı'' yla Analizi'' Cumhuriyet Bilim ve Teknoloji Dergisi
Kaynak, O.(2012a) ''Neden Dik Yürüme, Büyük Beyin ve Kılsız Beden ? yazısı üzerine eleştirel notlar'' Bilim ve Gelecek Dergisi sayı: 96/ 91
Kaynak, O.(2012b) ''an Analysis of Australopithecus Sediba from a New Viewpoint: Mentis Eversionis'' , 18th Congress of the European Anthropologial Assocition Human Evolution and Absract Booklet s:50
Kaynak, O.(2013a) ''Processes and Mechanisms of Human's Evolution Towards the Intelligent Living Being'' Gordon Research Conferences
Kaynak, O.(2013b) ''Doğal Seçilim İki Ayaklılığı ve Büyük Beyni Seçiyor mu?'' V. Ulusal Biyolojik Antropoloji Sempozyumu Bildiri Özetleri Kitapçığı s:17
Kaynak, O.(2013c)''İnsan Evriminde Üç Sıçrama'' Cumhuriyet Bilim Teknoloji Dergisi s:1391/13
Kaynak, O.(2014) ''The Three Leaps in Human Evolution'' 19. European Anthropological Association Congress, Moskova Üniversitesi Bülteni . SERİ 23 : Antropoloji Yayınevi : Moskova Devlet Üniversitesi ( Moskova ) ISSN : 2074-8132 - №3 . - S. 91
Kaynak, O.(2015) ''Major Transitions in Human Evolution Discussion Meeting'' The Royal Society
Kaynak, O.(2017a) ''The Three Leaps in Human Evolution'' Gordon Research Conferences, Boston, USA
Kaynak, O. (2017b) ''Three Leaps in Human Evolution'' AICSSH & AICMSE 2017 Conference Proceedings Oxford, UK, ISBN: 978-1-911185-38-3
Mayr, E.(2008 ) Biyoloji Budur – Canlı Dünyanın Bilimi (This is Biology – The Science of the Living World)
Trevathan, W. (1987) Human Birth: An Evolutionary Perspective.
