Evolution of Face and Beauty Through TimeChapter 1

An excellent parallel to the concept of evolution is seen in the Indian mythology as the ten incarnations of Lord Vishnu, the sustainer of the universe. The nine incarnations were in the following order. (1) The fish, an aquatic vertebrate. (2) The tortoise, an amphibian. (3) The pig, a mammal. (4) Narasimha, half man and half animal. (5) Vamana, the dwarf man (bushman). (6) Parasurama, the wood cutter having an axe as his armament. (7) Sreerama, the hunter having bow and arrow as his armament. (8) Balarama, the farmer having a plough as his tool, depicting the cultural evolution from a forest dweller to an agriculturalist. (9) Krishna, the glorified lover of all times and a modern statesman. The tenth incarnation is yet to come. He is Kalki the destroyer who comes for the final judgment. Most of the mythologies predict this plight to the human race (Figure 1-1).

Climatic cooling during the late Miocene period (6.0 to 5.3 million years ago) might have triggered speciation of Hominin super family. This period is marked by the speciation of other mammalian families as well. The diversification of humans and chimpanzees took place somewhere during the late Miocene period. This period was marked by climatic changes compounded by simultaneous global cooling and drying trend. However the lack of sufficient fossil records during this period puts a question mark on the veracity of this generally accepted postulate.^5,23

These geological events made the common ancestors of humans and the chimpanzees to split as rain forest dwellers of West Africa and open dry habitat dwellers of East and perhaps North Africa. The former evolved into arboreal modern chimpanzees and the latter to the modern humans.² The period of separation of the humans and the chimpanzees from their common ancestors is debatable. The late hypothesis theory based on molecular studies supports the date of separation as 4 to 5 million years ago. But some recent gene analysis suggests the date as 5 to 6 million years ago. Some authors put it to as 10.5 million years.²⁸

In 1655 Isaac de la Payrere from France discovered stone tools used by primitive men. He claimed that these tools belonged to men who lived before Adam. His findings were condemned and books were burned by the church authorities.2

As the common ancestor of apes and humans climbed down from the tree and started walking on their hind limbs. Their forelimbs became free and took over many of the functions of the jaws, like fighting, carrying, holding, etc. Development of an apposable thumb facilitated tool making, which in turn helped the enhancement of intelligence, and vice versa (Figure 1-2). Though modern humans and apes show stark differences in their posture, structure and morphology, the differences were less with the earliest hominins, and the subtle differences were mainly due to bipedalism (walking upright on two legs) which brought the foramen magnum forward. The pelvis became bowl shaped as it shortened and broadened (Figure 1-3).²² Many factors were responsible for the facial changes. Receding jaws and expanding skulls made anthropologists state that the “Brain case is expanding at the expense of the jaws”. Several environmental, developmental and evolutionary factors played their roles in the changes that have taken place in the physical characteristics of the humans. This Chapter briefly deals with the evolution of the human face and its beauty.

The modern man known scientifically as Homo sapiens sapiens belongs to the larger family ‘Hominidae’. Living humans, all human ancestors and many extinct members of the Australopithecus belong to the ‘Hominidae’ family. Our immediate biological cousins are Cercopithecoidea (old world monkeys and apes) and Pongidae (chimpanzee, gorilla and orangutan). It is generally accepted that we are not the direct descendants of any of the existing monkeys or apes or even the old world monkeys. Instead, we had a common ancestor.

In 1856 a strange skull was discovered in the Neanderthal valley in Germany. The skull belonged to a hominid later named as Homo neanderthelensis. Ernst Heinrich, a German Scientist opined that the skull is half human and half ape. (Though Charles Darwin had completed his voyage of the Beagle, his book ‘Origin of Species’ had not come out at that time. It was published on the 24th of Nov 1859).⁷

In the book ‘The Descent of Man’ Charles Darwin wrote, “We must acknowledge, as it seems to me, that man with all his noble qualities, with sympathy which feels for the most debased, with benevolence which extends not only to other men but to the humblest living creature, with his god like intellect which had penetrated into the movements and constitution of the solar system – with all these exalted powers, man still bears in his bodily frame the indelible stamp of his lowly origin”.⁸ In 1890, a Dutch physician Eugene Dubois opined that the skull got from 4the banks of a river in Java is a link between man and ape. Johansson is credited with the finding of the fossil skeleton of ‘Lucy’ (Australopithecus afarensis) in Ethiopia the upright walking mother of all modern humans. Members of the family Hominidae are the bipedal primates.

Ardipethecus Ramidus (‘Ardi’ means ground or floor, ‘Ramid’ means root) lived about 4.4 million years ago. A piece of the Foramen magnum indicated upright posture. The leg and pelvis indicated a semi-bipedal mode of locomotion. Fossils of these species were discovered by White, et al in 1994. This species is at present considered the ancestor of Australopithecines.³⁷

From Australopithecus the evolution of humans took place at a breakneck speed. Reasons attributed are many:

During the last 2 million years there was co-existence of different species of hominid species.

The striking difference between humans and their closest living relatives (chimpanzees and Gorillas) is in the size of the brain and their lifespan. The brain is larger by a factor of 3 to 4 and the lifespan is larger by a factor of 2. According to Kettard S Kaplan and Arthur J Robson the larger human brain is an investment with initial costs and later rewards.¹⁶

Cranium of modern man is characterized by its globularity and facial retraction. According to Daniel E Lieberman and associates, the developmental changes that led to the modern cranial form were derived from a combination of shifts in cranial base angle, cranial fossa length and width, and facial length.¹⁹

An interesting study has been conducted by WP Rock et al in 2006. They have compared human skulls from the 14th, 16th and 20th centuries. They found that the horizontal measurements in the anterior cranial fossa and the maxillary complex were greater in the modern group. Cranial vault, especially anterior cranial fossa, was significantly higher in modern skull. They concluded that the medieval ancestors had more prominent faces and 5smaller cranial vaults than modern man. The angle SNA (S-Sella, N-Nasion, A-Deepest point of the maxilla in the anterior part below the anterior nasal spine) was lesser in modern man indicating the reduction in the size of the maxilla. The prefrontal area is accepted to be the seat of intelligence. Increased intracranial dimension and high forehead of the modern man are evidences of the increase in brain size over centuries.²⁶ This evidence is good enough to show that evolution is occurring in a much faster pace than generally thought.

Brain size in relation to the basicranial length is an important determinant of the basicranial angulations. Spoor et al (1999) and Liebermann (2000) opined that differences in cranial base angle are more likely to account for facial retraction in modern humans.^20,32

Absolute brain volume has more than tripled from A. afarensis to H. sapiens and the relative brain size has more than doubled.²¹ Despite the lack of fossil proof, biologists of early days who were proponents of evolution, like Lamarck, Thomas Huxley and Charles Darwin, speculated that bipedalism preceded encephalization. Their speculation was proved right later by archeological studies and fossil findings.²⁰ The frontal lobe and cerebrum are supposed to be the seat of intelligence. One of the striking features that delineates Homo sapiens (the wise man) from his ancestors is the prominence of the forehead by its steep rise. The modern human skull looks infantile compared to the Neanderthal skull with the cranium more round and delicate. Comparison of the brains of amphibians, reptiles, birds and mammals shows the increase of the brain size mainly due to the enlargement of the cerebrum (Figure 1-4).

Certain other morphological adaptations occurred along with bipedalism. These include Valgus knee angle, anteriorly placed Foramen Magnum and short, broad, bowl shaped pelvis.⁴ As the jaw size reduced the masticatory muscles also reduced in size. For the ape the jaw is broadest at the canine area. But in man it is broadest at the condyle region. This is because the skull has expanded in lieu of the enlarged brain, pushing the glenoid fossa laterally (Figure 1-5).^5,18

During the embryonic development the mandible develops as two halves which got joined in the midline. This area is subjected to great strain owing to the powerful muscles of the apes and the pre-humans. To contain the stress at the inner side of the anterior part of the jaw a shelf of bone called the ‘Simian shelf’ developed. In humans the muscle size reduced, the jaw size reduced and the simian shelf disappeared. The remnant of the shelf is the genial tubercles to which the genioglosses and geniohyoid muscles are attached.6

Among the Hominins, H. sapiens is the only species having a well developed chin. A protruded chin makes it vulnerable to injury in a fight or accident. In response to it the neck of the condyle has become thinner and the sigmoid notch became deeper. A direct force on the chin will be transmitted to the condyle. If the neck of the condyle is broad and strong the force could fracture the temporal bone and in turn injure the brain, killing the victim. Hence, a thin condylar neck was a favourable evolution for the protection of the brain.

According to Rebecca Rogus Ackermann genetic drift should be the primary cause for facial diversification. However selection also might have played a role in the changes in facial morphology during the evolutionary process.¹

Reduction in the size of the jaws during human evolution is associated with its shift under the skull. This had an influence on human dentition. A beautiful regular smile is the result of a delicate balance among many different facial genes. And so a regular smile, the sign of good genes, some theorists claim, is the underlying sexual significance of physical beauty.⁶

The face, jaw and teeth of Mesolithic humans of 10,000 years ago were about 10% more robust than those of modern humans. 30,000 years ago (Paleolithic period) it was about 20 to 30% more robust. Relative to the body size the molars of A.afarensis are 1.7 times larger than expected compared to that seen in modern species of Hominins. An interesting finding to be noted is that the tooth size has increased in A. robustus and further evolution decreased the tooth size. This could be attributed to the food processing habits (using tools), which the later forms developed.^{34, 35}

In earlier primates and hominins the brow ridge is very large like a penthouse protecting the eye. These large brow ridges act as buttresses to resist the stress exerted by the massive jaws while chewing. As the jaws and the muscles of mastication became smaller, the parietal bone became prominent. The brow ridges lost its function and got reduced in size.

Compression of the lateral part of the maxilla and the movement of the orbits medially have narrowed, elevated and arched the nasal bone forming the bridge of the nose. Tip of the nose is not vestigial, but evolving. The shape of the nose in man is mainly due to the regression of the jaws. The rising bridge of the nose might have evolved to give resonance to the voice.

Following is a brief list of major facial and cranial changes that have taken place during evolution of the hominins.

Above lines by poet John Keats shows the positive influence of beauty on emotional perception. He glorifies beauty. True beauty radiates vitality and happiness.

Opinions about the beauty of the face abound as it is more subjective than objective. Some consider attractiveness as having average ingredients. However Francis Bacon in his ‘Essays on Beauty’ opines that ‘There is no excellent beauty that hath not some strangeness in the proportions’.³ However symmetry has got a positive influence on facial beauty.^12,33 Attractiveness is related to positive physical qualities.

Theory of ‘survival of the fittest’ was proposed by Charles Darwin.⁸ Survival could be by challenging the odds or by adapting to the periodical positive and negative changes taking place in nature. Fitness often is a harmonious and balanced blend of both. Simply getting adapted to the surroundings to exist doesn't mean progress; if so, the thrust of evolution is not to advance but to compromise and the result will be just survival or passive existence.

Anaerobic metabolism has been replaced by aerobic metabolism in higher forms of life since it is more efficient in the production of energy. One molecule of glucose can produce two ATPs in anaerobic metabolism, but the same molecule can produce 8 ATPs by aerobic metabolism. Efficiency in metabolism and production of energy had some compromise on existence reminding us that mere existence/survival is not the sole aim of life. As evolution progressed, organs got specialized and the regenerative capacity of the organism regressed.

A single celled organism never dies by aging, but multiplies, by binary fission. It dies only by injury or starvation. Next step, in the evolution of reproduction, was conjugation and division where genes were allowed to mix. Single celled organism by evolution became a multicelled organism with functional differentiation of parts and had to accept death by aging. In lower forms each cell is a stem cell; which had the property to grow into a full organism. Vegetative reproduction in plants is an extension of this phenomenon. Gradual evolution has seen sexual differentiation and sexual reproduction. This has improved and increased the pace of evolution by mixing of the genes and promoting selection.

Sexual reproduction paved the way for selection of a partner. Purpose of evolution, it appears, is to attain perfection, and hence it is important that the organism moves on to better fitness by each generation, and to a better species. During the progression of evolution, the stress shifted from physical to intellectual evolution by gradual refinement of the nervous system to a well formed controlling brain. This quantum shift might have happened in a reptile (Figure 1-7).²⁷ (In the story of genesis in Bible, the fruit of knowledge is given to Eve by a reptile)

Sexual reproduction brought the need for the selection of a partner for reproduction. To produce a better offspring a better partner is important. Attractiveness became an important criterion for selecting a partner for reproduction. External features representing health, vitality, and intelligence, by default became attractive. During the cascade of mutations and selections during the evolutionary process attractive features got incorporated into fitness and the ‘survival of the fittest’ became akin to ‘survival of the prettiest’. Thus prettiness came to represent brightness and fitness. True beauty evokes pleasure (a thing of beauty is a joy forever’ John Keats) and pleasure is perceived in the subconscious limbic system, not in the cognitive neo cortex.

Many studies have showed that baby face characteristics like large and round eyes, larger domed forehead and well defined chin are attractive features especially for females. It is to be noted that during the hominin evolution, tendency towards retention of childhood characteristics is evident. This tendency is called Neoteny.¹⁵ Humans exhibit a number of neotenies compared to apes. In Chimpanzees adulthood starts by 2 to 3 years. In humans it is by 14 years only. Some of the features of the face that are attractive are brown skin, full lips, larger distance between the eyes, larger and darker eyelashes, darker eyebrows, high cheek bones, narrow nose, etc. People with more attractive features were assessed to be more successful, contended, pleasant, intelligent, sociable, exciting, creative and diligent.¹¹ This finding poses a question whether intelligence and other positive qualities cultivate attractiveness, or, the confidence imparted by attractiveness in turn makes people more intelligent and creative. Infact, these are interdependent and contributory. If attractiveness and intelligence are extrapolated in time, we can deduct that both are the two main factors in selection of a mate – survival of the prettiest and the brightest or in other words, survival of the fittest. This plays an important role in evolution.

Leonardo Da Vinci has drawn the ‘Vitruvian man’ relating divine proportion to the human anatomy. The body when in divine proportion is able to effect maximum efficiency with least effort and also imparts better aesthetics, reflects health and provides survival advantages. Perfection ensues where function and beauty meets. Attractiveness has been a lure since the evolution of sexual reproduction. The pretty and the bright ones stand a better chance in the competition for a partner. Proper proportion expresses fitness and prettiness. On the aspect of selection and propagation of genes and subsequent evolution, function always precedes form. Hence it can be postulated that prettiness is a manifestation of fitness and brightness.^14,24

Attractive physical features provide external clues to health and fertility status, the two most important requirements for genetic success. “In civilized life, man is largely influenced in the choice of his wife by external appearance”. Charles Darwin noted so, way back in 1871. Longitudinal data suggest that attractive women tend to marry men of high occupational positions. (Is the dough, the marker for men?). Baby like neotenous traits are considered attractive for females.

Testosterone, a male hormone, makes the person grow big and also causes lower jaw to grow longer. Estrogen a female hormone increases the lip volume.³⁶ Estrogen also increases the fat deposits on the buttocks and the thighs and increases the utilization of abdominal fat giving the woman an hour glass (gynoid) appearance which is associated with menarche.³⁰ Large breasts give an impression that there is plenty of milk for the child which is important for a healthy offspring, a fundamental prelude to propagation. Wide girdle bones can house a large head of the foetus which means a large brain volume (more intelligence). (High heeled foot wears worn by ladies give prominence to both hips and brests and make them more desirable as a partner.). Humans are considered to be the species having the maximum pain during labor and the highest maternal mortality rate. This could be due to the fast intellectual evolution (large head of the fetus) and not so fast physical evolution (pelvic bone). For taking the forbidden fruit of knowledge the woman is cursed by God that she will deliver her child in pain (Genesis, Old treatment, Bible).

Studies have shown that young babies are attracted by beautiful faces which suggests that humans have got an innate capacity to appreciate balance and harmony.

As face is the prime seat of expression it is the area of attention. Study of evolution of face and skull gives insight to the evolution of facial beauty. It is said that during the evolutionary process the brain case got expanded at the expense of the jaws. This statement simply means that brain volume is increasing and jaw size is reducing.

To analyze beauty and to analyze the proportion of expansion of brain case and reduction of the jaw size, a modified cephalometric analysis is applied.

When a line is divided in such a way that the ratio of the shorter section to the larger section is equal to the ratio of the larger section to the whole line, this is supposed to be the most aesthetically pleasing point at which to divide a line. This is known as the golden proportion and is represented by the symbol φ (Phi). The name ‘Phi’ is derived from the Greek Sculptor Phidias who used golden proportion in his most famous work Pantheon.^9,13 This proportion is linked to many aspects of beauty that Kepler called it ‘Divine proportion’.

Phi is supposed to be the most pleasing proportion and is used in the construction of Greek temples and by Michelangelo and Da Vinci in their paintings. Michelangelo's famous painting ‘Temptation and Expulsion from Eden’ is a well known example of this proportion.²⁴ It appears that in nature this system of designing is abundantly observed in living and even non-living structures. Design of leaves, petals of flowers, shells, etc. use a series called ‘Fibonacci series’ (0, 1, 1, 2, 3, 5, 8, 13, 21,…….), where the adjacent two numbers are added to get the third number. It is interesting to note that the proportion between the adjacent two numbers is near about 1.618 which is known as the golden or divine proportion (Figure 1-12).

The proportion is calculated between the cranium and the face on two different planes – frontal and lateral. The distances between Vertex (V) and the nasion (N) and from the nasion (N) to lower border of the mandible are taken in a vertical plane. This proportion in the frontal plane appears to approach the golden proportion as the evolution progresses (Table 1-1).12

On the lateral plane MN plane, virtually divides the cranium and the face. As the brain case is expanding and the jaw size is reducing, this proportion approximate the divine proportion as evolution progressed. If the extrapolated graph (of the proportions from the pre-human to human face through different species) is projected to the future we can deduce that it will take another million years for the present proportion of skull and face to reach divine proportion (Figure 1-13).

If we go through the archeological history of the Hominidae, branching of the humans took place about 7 million years ago and from then about 7 to 8 species have emerged to reach the present Homo sapiens. It is also to be noted that during the first 3 to 4 million years from the branching of the Hominid from his cousins, the apes, evolution was slow and took a faster pace during the latter half. So we can expect another two species of humans evolving during the next one million years. By then the adult face may look very similar to that of the present child with large head, large eyes, small jaws with an oval face. The children's face often exhibit the divine proportion.

The Superman concept of Nietzsche and the statement “Man is poised between the beasts and the gods” by Plotinus, points to the evolution of Homo sapiens to a more beautiful and intelligent being. Can we call the future two spices ‘Homo sapiens super’ and ‘Homo sapiens divine’ respectively? (Figure 1-14).

May I quote from the scriptures “God is sleeping in minerals, awake in plants, walking in animals and thinking in humans”13

Life could be one of the properties of matter. Evolution is an innate quality of life, and may be the quest of nature/matter for perfection, where trial and error/rejection and selection are the norms. By the wars between nations, the strife between religions and the fights between races, molesting nature with atomic wastes, suffocating her with pollution and hindering her plans by eugenics, are we on the path of self inflicted extinction? Are we, as Sir Winston Churchill said, on the verge of “a new dark age made more protracted and perhaps more sinister by the light of perverted science”.

Are we misusing the self awareness and intelligence we have gained through evolution? If so, we may be subjected to nature's wrath-extinction and a future intelligent species (if any) may rename us ‘Homo stupid’.