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Wednesday, 21 January 2015

172) The “25 Euro Silver-Niobium Coin Series: (xii) 2003 onwards minted by the Austrian Mint: Twelfth Coin in the Series: “Evolution” (2014):



172) The “25 Euro Silver-Niobium Coin Series: (Part xii): 2003 onwards minted by the Austrian Mint by using Niobium and Niobium metal insertion technology for the first time anywhere in the World of Numismatics:  The Twelfth coin in the Series: “Evolution” (2014):

The theme of this coin is Evolution and it illustrates the story of the development of Homo sapiens from other species.

The concept of human evolution, is as old as Charles Darwin’s “On the Origin of Species” (published in 1859), or perhaps even older in a nascent way.

Several mechanisms have led to the understanding of human evolution, which has been facilitated by electron microscopes, carbon dating of fossils and remains of ancient man etc.

One of the most fruitful methods to learn about human antecedents is to observe living animals that resemble man’s direct ancestors.

 Among these distant cousins of man are tree shrews, which were primitive animals not very different from the earliest mammals. Another one is the coelacanth, a rare fish descended from the ancestors that had inside their fleshy fins, bone connections uncannily like the bones of human arms and legs. On limbs much like these, the first invertebrates crawled up onto the land.

Today, even animals distant from man can reveal insights into his past. In particular, much about ancient behaviour is deduced from studies of modern animal behaviour. Man is a social animal, for example, who was not the first to find strength in numbers. Several types of insects did so many millions of years ago, and the result was the wonderful world of the social insects – ants, bees, wasps, termites etc. – whose civilised colonies can be found in every habitable part of the World. Although the insects provided none of man’s heritage, their group living offers illuminating parallels to his own societies.

Similar parallels can be found in the tightly structured group living of such animals as wolves and baboons. However, none of these low-level societies of mammals, show signs of progressing to a higher level. This feat, which literally changed the face of the Earth, was accomplished by erect-walking primates who were the direct ancestors of man. Their hunting groups, which at first were like wolf packs, gradually became more tightly organised. Their descendants developed speech for quick and accurate communication. They learnt how to use fire and fashion weapons of wood, stone or bone. They built shelters to protect themselves from inclement weather and acquired clothing that enabled them to live comfortably in cold climates.

Thereafter, the history of man is largely that of his technical advances and social achievements. Perhaps, the greatest achievement was the almost simultaneous development of agriculture and animal husbandry. When the first farmers had acquired domesticated plants and animals, they turned unproductive land into cultivated fields and pastures. Human population increased enormously and pushed into areas inhabited thinly by wandering hunters. Villages appeared, acquired walls and fortifications, followed by cities, countries and empires. In not more than 1.3 million years – a miniscule period of time on the evolutionary scale – from the appearance of the first creature that could be called human, mankind has changed from a scarce and wandering hunter race to being the undisputed lords of planet Earth.

Man dominates the animal kingdom not only because he possesses a big brain capable of rational thought, but also some physical traits of overwhelming significance - a skeleton built for walking upright, eyes capable of sharp, three dimensional vision in colour and hands that provide both a powerful grip and nimble manipulations.
A Timeline of Life’s evolution:

·         Our solar system is thought to have formed from a giant rotating cloud of gas and dust known as a proto-planetary disc some 4.67 billion years ago.  The sun formed at the centre of the disc and the planets gradually formed around the Sun in a process called accretion. The Earth’s moon formed as a result of a collision between Earth and a Mars sized body called “Theia”. The impact caused a portion of the combined mantle of earth and Theia to be expelled into space, eventually forming the Moon.

·          It is believed that the Earth thereafter went through a violent period of near-constant collisions with large asteroids and comets. From fossil evidence, it appears that life existed on Earth some 3.5 billion years ago.

·         Around this time, one-third of planet Earth consisted of a gigantic continent, covered with rocks, mountain ranges ragged trenches and patches of bright minerals across stony plains. The cooling of the Earth allowed for crust formation and the condensation of water present in the atmosphere formed the Earth’s oceans which rolled over two-thirds of the planet. Almost everywhere volcanic cones and fissures spouted dust and vapour or gushed crimson rivers of lava that hardened into black rocks/mountains. The climate, uniformly tropical and humid, was marked by local fogs, clouds, rain and lightning storms. Winds and waves scoured and ploughed the land.  The  sea was empty of life and the land shows no traces of green or life. There was no breathable free oxygen in the atmosphere, which consisted mainly of water vapour, hydrogen and two poisonous gases, ammonia and methane which dissolved and bubbled in the waters of the sea and land.

·         Ultraviolet radiation, which was inimical to life, fell upon the planet from the Sun. In such an environment, none of the higher forms of life that would later populate the Earth could have survived. Nevertheless, within the hostile environment of primitive Earth were the very prerequisites for the creation of life which came in three stages, each stage transforming the Earth to bring forth the World that men will eventually inhabit.

·         For 1000 million years, since the birth of the planet, the physical constituents of life – carbon, hydrogen, oxygen and nitrogen, the basic ingredients of organic substances making up all living things – had been accumulating in the atmosphere and the waters.  There was also electricity in the lightning that ripped through the sky, radiation, in the UV light, heat from the volcanoes etc. which would act as a catalyst for the “creation” of life. In the warm primal sea, true life was about to emerge which will remain in the sea for more than 2000 million years constantly changing in form and function.

·         Gradually, the primitive Earth’s energy and raw materials began to generate the stuff of which life is made – notably the organic compounds called amino acids, which are the building blocks of proteins and also of DNA, the carrier of hereditary patterns for all living things. The sea became rich in these materials and the primitive sea now contained what is termed as a “kind of organic soup”. As yet there was no sign of life. Then the natural forces made some of the available materials join together into new and still more complex substances some of which had a surprising capacity to reproduce themselves and proliferate – these were the first living organisms on earth. They were microscopic and resembled modern viruses, bacteria and fungi.

·         As there was no free oxygen to breathe, these organisms got the energy to sustain themselves by breaking down the materials of the organic soup, through a chemical action called fermentation which is still employed by many bacteria and fungi.  However, these living forms by continuously feeding upon the organic soup would have exhausted the organic soup itself. This was a fatal flaw that sent the Earth’s original life forms down an evolutionary dead-end, because these life forms were consuming and destroying the very conditions needed for their own survival.

·          About 3000 million years ago, life got a fresh impetus on Earth. A major waste product of fermentation is carbon dioxide – which became the starting point for new forms of life containing the substance chlorophyll. Chlorophyll made possible the process called “photosynthesis” which converted carbon dioxide, water and sunlight into sugar, which then became food for chlorophyll containing forms of life. These forms, freed from dependence upon the ready-made molecules of the organic soup, flourished in great numbers, slowly evolving into all the varied members of the plant kingdom. These, in turn, produced another opportunity for life on Earth.

·         Photosynthesis, like fermentation, has a waste product – oxygen – which over a period of 1000 million years penetrated the waters in which the first plants grew.  The evolution of photosynthesis, allowed cyano-bacteria to convert light energy to chemical energy. The formation of oxygen molecules as a by-product of photosynthesis eventually transformed the Earth’s atmosphere and paved the way for bio-diversity on the planet. The oxygen was lethal to many of the early fermenting organisms, but took another 1000 million years to accumulate in the atmosphere, and paved the way for different, more efficient forms of life. Almost 1000 million years ago, certain microscopic forms began to sustain themselves by combining oxygen with living material – from plants or from other forms like themselves.

·         These oxygen breathing animals, the earliest ancestors of man, soon swarmed in the sea, feeding upon plants and upon one another. From minute one-celled blobs, they developed in a fairly short time into highly specialised creatures. Some were mobile and could propel themselves through the water with tiny, whip-like tails, others floated passively or anchored themselves to undersea slopes. Eventually they became sponges, jelly-fish, worms and coral.

·           Some of the microscopic blue-green algae, the first plants to evolved, trapped bits of sediment and layer by layer, built up huge structures called stromatolites which still exist today. We know little about these first organisms.



·         The above illustration shows successive layers of microbes and sediment result in the striated pattern of growth, which stands like upside-down ice-cream cones which were produced by the activity of sheets of blue-green algae (cyanobacteria) trapping and binding sediment in layers, stand on a Precambrian sea floor around 1000 million years ago. Stromatolites like these grew as tall as 50 feet, but their odd shapes –rock formations, striated patterns of growth were determined by an as yet inexplicable process.



These stromatolites still present today are hardened sediment once bound by now-decayed blue-green algae, some 2000 million years ago.

·         Recent studies of stromatolite samples suggest that microbes may have existed on Earth as early as 3.5 billion years ago. Some other samples have confirmed that microbial life has been dated back definitely to 2.7 billion years ago. This indicates that life evolved on Earth sometime during Earth’s tumultuous first billion years.

·         Geological evidence suggests that life on Earth was limited to prokaryotic bacteria like life until around 2 billion years ago, which lacked a discrete nucleus (prokaryote is Greek for “before nucleus”). Modern eukaryotes (eukaryote is Greek for “true nucleus”) are characterised as having membrane bound organelles, such as mitochondria and chloroplasts, as well as a membrane bound nucleus. It is believed that the organelles and nucleus may have evolved as a result of an ancient symbiotic relationship between different bacteria. Eventually, the bacteria that went on to become organelles transferred the bulk of their genetic information to the host cell genome and lost their ability to survive independently.

·         Around 1.2 billion years ago, multi-cellularity is believed to have evolved several times in the history of life on Earth. According to a scientific thought, multi-cellularity evolved as a result of a symbiotic relationship between cells of the same or different species, eventually leading to interdependency.

·         The fossil record from the Cambrian period i.e. around 500 to 600 million years shows a sharp increase in the diversity and number of complex animals during a relatively short time span in Earth’s history. The cause of the Cambrian Explosion is unknown, although it is believed that the rise in atmospheric oxygen or other environmental changes may have played a significant role.

·         For over 150 million years (225 to 70 million years), dinosaurs populated the Earth, eventually reaching every continent on the Earth. Their sudden mass extinction known as the Cretaceous-Tertiary Extinction Event is thought to have been caused by a large asteroid impact or an increase in volcanic activity eventually leaving the planet for another form of life to emerge, evolve and rule the planet – Man!!    
The Geological Time Chart:

GEOLOGICAL ERA
PERIOD
EPOCH
DATE
BIOLOGICAL FEATURES
CAINOZOIC
Quarternary
Pleistocene
10000 to 2 million 
First True man: Homo erectus*

Tertiary
Pliocene
2 to 10 million
First man-like apes


Miocene
10 to 25 million 



Oligocene
25 to 40 million
First monkeys and apes


Eocene
40 to 60 million



Palaeocene
60 to 70 million
First primates : prosimians
MESOZOIC
Cretaceous

70 to 135 million
First flowering plants and Last Dinosaurs

Jurassic

135 to 180 million
First birds

Triassic

180 to 225 million
First mammals, First Dinosaurs
PALAEOZOIC
Permian

225 to 270 million


Carboniferous

270 to 350 million
First coniferous trees, first reptiles and First insects

Devonian

350 to 400 million
First forests, first amphibians and first bony fish

Silurian

400 to 440 million
First land plants, first fish with jaws

Ordovician

440 to 500 million
First vertebrates: Armoured fish without jaws

Cambrian

500 to 600 million
Invertebrate fossils: first shell-bearing animals
PRECAMBRIAN 


600 to 4500+
Million

First Living Things: Algae & Bacteria

*"Modern man' is called Homo sapiens sapiens (in Latin) which only means “intelligent man”. The oldest known fossils found in Asia & Africa are about 40000 years old. 

Palaeozoic means “ancient life”, Mesozoic means “middle life” & Cainozoic means “recent life” in Greek.  

Evolution from soups to cells – the complex building blocks of life & Process of Natural Selection:

Living things, even ancient organisms like bacteria are very complex. All this complexity did not spring fully-formed from the primordial soup. Instead, life originated in a series of small steps, each building upon the complexity that evolved previously.

·         Simple organic molecules, similar to nucleotides: These were formed as the building blocks of life at the origin of life. The organic molecules were synthesized in the atmosphere of early Earth and rained down into the oceans. RNA and DNA molecules – the genetic material for all life – are simply long chains of nucleotides.

·         Replicating molecules evolved and began to undergo natural selection: All living things reproduce, copying their genetic material and passing it on to their off-spring. Thus, the ability to copy the molecules that encode genetic information is a key step in the origin of life, without which life would not exist. This ability probably first evolved in the form of an RNA self-replicator – an RNA molecule that could copy itself. Self-replication opened the door for natural selection. Once a self-replicating molecule formed, some variants of these early replicators would have done a better job of copying themselves than others, producing more “off-springs”. These super-replicators would have become more common – i.e. until one of them was accidentally built in a way that allowed it to be a super-super-replicator – after which this variant would take over. Through this process of continuous natural selection, small changes in replicating molecules eventually accumulated until a stable, efficient replicating system evolved. This development in the broader perspective led to the continuous extinction/near extinction of several species.

·         Replicating molecules became enclosed within a cell membrane: The evolution of a membrane surrounding the genetic material provided two advantages: the products of the genetic material could be kept close by and the internal environment of this proto-cell could be different from the external environment. Cell membranes encased replicators quickly out-competed “naked” replicators.

·         Some cells began to evolve modern metabolic processes and out-competed those with older forms of metabolism: Upto this point living organisms relied on RNA for most jobs, however, this changed when some cells evolved to use different types of molecules for different functions: DNA (which is more stable than RNA) became the genetic material, proteins (which are often more efficient promoters of chemical reactions than RNA) became responsible for basic metabolic reactions in the cell and RNA was demoted to the role of a messenger, carrying information from the DNA to protein-building centres in the cell. Cells incorporating these innovations easily out-competed “old-fashioned” cells with RNA based metabolisms.

·         Multicellularity evolution: Around 2 billion years ago, some cells stopped going their separate ways after replicating and evolved specialised functions. They gave rise to Earth’s first lineage of multicellular organisms, such as red algae etc.

The evolution of the spine:    

From the simple structure in a pre-historic fish to a complex instrument in modern man, the spine has evolved to support body and head and to aid intricate movements:

An undifferentiated spinal column served the eusthenopteron, which was an early bony fish of 375 million years ago.

Its similarly shaped vertebrae, joined to short ribs, gave swimming muscles something to pull against. The uniform ribs along eusthenopteron’s spine lent only a lateral undulating movement. 
  The amphibian ichthyostega required a sturdier spine than the eusthenopteron because on the land there was no water buoyancy to help support its body weight.

Its vertebrae, as a consequence, were more solidly constructed. Its large ribs helped it to hold up its head on land as well as supporting its body.  

The vertebrae of the mammal-like reptile thrinaxodon, even more closely locked together than those of ichthyostega and had specialised shapes and sizes.

 For example, the vertebrae were large near the limbs and smaller in the lighter tail. Thrinaxodon’s neck ribs had shrunk, thus enabling it to move its head far more easily than ichthyostega.

A modern tree shrew that resembles extinct primitive mammals is capable of moving along the ground as well as climbing trees, arching and extending its backbone as it moves.

Its vertebrae are designed for both types of movements. The tree shrew’s highly flexible neck is partly due to the shrinkage of neck ribs, now mere vestigial bumps.

The ancient primate mesopithecus, although a quadruped, was capable of briefly supporting its body on its rear legs while reaching and grasping, and its backbone was accordingly specialised – rigid when upright but flexible enough to allow it to travel through trees.

Its vertebrae had acquired a variety of shapes. The small cervical or neck vertebrae permitted head movement while supporting the skull either vertically or horizontally. The large vertebrae in the lumbar region of the lower back supported propulsive movement. Mesopithecus’ head movement depended partly on the “atlas-axis complex” of two neck vertebrae. The top one enabled the head to move up and down and is therefore called the “yes” bone. The axis, which is just below gave sideways head movement, hence it is called the “no” bone.

To provide support for man’s upright, biped posture, the vertebrae of his spine are strongly locked together in a flexible, vertical rod.

The vertebrae are increasingly heavy from the top, down to the hips, where the weight of the body is transmitted to the legs. The backbone must not only be strong enough to bear most of the weight, but has to be flexible enough to enable man to balance on two legs. Nevertheless, man’s vertebrae are separated by easily damaged discs and back trouble is a common complaint.

Man’s upright posture has also given him a head position that in relation to his spine is different from the position of the heads of semi-erect primates. The top of the spine has migrated from its position in the back of the skull, to a point almost directly under the skull. Thus man’s head is neatly balanced at the top of his fully erect spine and there it stays as he freely moves his ribless neck.

Deoxyribonucleic acid (or DNA):

The structure of the DNA was discovered in 1953 by Francis Crick and James Watson, who were awarded the Nobel Prize in 1962 in Physiology or Medicine for their work leading to this discovery.

Deoxyribonucleic acid, commonly known as DNA is a code for life/ hereditary material found in almost every living organism. It is found in strands known as chromosomes in the interior part of a cell – the nucleus. Nearly every cell in a person’s body has the same DNA. Most DNA is located in the cell nucleus (where it is called nuclear DNA), but a small amount of DNA can also be found in the mitochondria (where it is called mitochondrial DNA or mtDNA).

Each chromosome contains genes which are blue-    prints of genetic information and are made up of segments of DNA. DNA also contains the blueprints for making proteins and for replicating itself.

The DNA molecule is a double helix, resembling a spiral/twisted ladder. The sides of the ladder are made up by alternating units of phosphate and a sugar, deoxyribose. Attached to the sugar units are rungs of the ladder, which are made up of combinations of bases. The information in DNA is stored as a code made up of four chemical bases: adenine (A), guanine (G), cytosine (C) and thymine (T). Human DNA consists of about 3 billion bases and more than 99% of these bases are in all persons. The order or sequence of these bases determines the information available for building and maintaining an organism, similar to the way in which letters of the alphabet appear in a certain order to form words and sentences.

DNA bases pair up with each other, A with T and C with G to form units called base pairs. Each base is also attached to a sugar molecule and a phosphate molecule. Together, a base, sugar and phosphate are called a nucleotide. Because of chemical attractions, only a few combinations of bases are possible for ex: A – T, T – A, C – G, or G – C. Length-wise, up and down the ladder, the bases form different patterns, for example: ATCGAT. Three of these bases together form a codon which encodes a single amino acid of a protein. The order of the bases in one strand (half) of the ladder determines the order of the bases in the other strand. For example, if the bases in one strand are ATCGAT, then the bases in the opposite strand will be TAGCTA.

An important property of DNA is that it can replicate, or make copies of itself. Each strand of DNA in the double helix can serve as a pattern for duplicating the sequence of bases. This is critical when cells divide because each new cell needs to have an exact copy of the DNA present in the old cell.

Before a cell divides, the DNA duplicates itself. The ladder splits length-wise, separating the bases of each strand. Then, with the help of special enzymes, the bases in each half ladder pick up their matching counterparts. The As attach to Ts, the Ts to As, the Gs to Cs and the Cs to Gs. In this way each new ladder becomes a duplicate of the original ladder. When the cell divides, the two new cells have identical DNA molecules.

DNA also determines the proteins a cell makes. It does this by encoding a messenger ribonucleic acid (mRNA) with information needed to make proteins in “cell factories” called ribosomes in the cytoplasm of a cell. The amino acid structure of each protein made by a ribosome corresponds to a particular sequence of bases in the DNA.
                   An illustration of a DNA double helix    

DNA molecules, found in chromosomes in the nucleus of every cell, carry the genetic information that determines inherited traits, such as skin colour, hair colour and body function. This information dictates the formation of proteins used by the body for growth and chemical processes.

If there is a mistake made during DNA replication and a sequence is altered (known as mutation), the composition of a protein may also be changed. The result may be a genetic disorder. There are over 4200 diseases which are known to be caused by genetic defects.

The Human Genome Project has mapped the entire genetic code of DNA.  This amazing scientific achievement holds out the promise of an understanding of, and possibly a cure for, inherited disorders.

Chromosomes:

A chromosome is a thread-like structure in the nucleus of a cell. Every chromosome consists of a double strand of DNA, arranged in a helical shape. Each chromosome contains many hundreds of genes.

The nucleus of every cell in the normal human body contains 46 chromosomes arranged as 23 pairs. The exceptions are ova (eggs) and sperm cells which have only 23 single chromosomes. One pair of the 23 pairs of chromosomes is the sex chromosomes. In males, one of the two sex chromosomes is shorter and contains fewer genes than the other – it is the Y chromosome. The other, longer, sex chromosome is the X chromosome. Males have an X and a Y chromosome, while females have two X chromosomes.

Some chromosome related abnormalities can be red-green colour and night blindness. Chromosomal abnormalities may arise through mutation of chromosomes or may be inherited. Some abnormalities are compatible with life, though usually the affected person may have physical or metabolic abnormalities which may be severe.

Genes: These are units of genetic information, passed from parent to off-spring and are found on chromosomes in the nucleus of each cell. Humans have 3 pairs of chromosomes and at conception, each parent contributes one chromosome of each pair. These chromosomes are then copied into each cell in the body. Chromosomes consist of DNA, with each gene being a section of DNA that instructs the cell how to make a particular protein.

The instruction is contained in the order or sequence of nucleotide bases (adenine, guanine, cytosine and thymine) of the DNA which codes the sequence of amino acids in the protein.

 Humans have approximately 100,000 genes, with each person having different combinations giving them their unique characteristics. Not all genes are active at any one time; gene expression can be inhibited or induced, depending on the function of the cell and the body’s needs.

Because each person has a unique genetic make-up, DNA analysis (DNA fingerprinting) can be used to identify individuals as in forensic medicine. Since we inherit half of our genes from each parent, the DNA of close family members contains more similarities than that of unrelated people.

Passing on genetic information: DNA, containing genetic information, is found within the nucleus of the cell. It is transcribed to mRNA within the nucleolus of the cell. The genetic information is then translated by ribosomes in the endoplasmic reticulum, into a sequence of amino acids which form a protein. The proteins are then incorporated by the Golgi apparatus into small packets (vesicles) and released at the cell membrane.

Gene sequencing: Each nucleotide base interlocks with a specific partner to form a base pair. Three base pairs form a codon and code for one amino acid. The order in which the bases are carried on a DNA strand determines the information contained in that strand.

Genetic code: Genetic information is contained in the myriad combinations of bases that exist along the length of the DNA molecule. A gene is a particular sequence of bases which codes for a specific protein. Proteins catalyse chemical reactions, build cells and tissues and ultimately confer characteristics on an individual. Even a single base alteration can lead to a disease.

Heredity:

Heredity is the genetic transmission of biological traits from one generation to the next. Millions of traits, ranging from eye colour and facial features to information the body needs to develop organs and tissues are transmitted through heredity.

Heredity operates through structures in the nucleus of the cell known as chromosomes of which there are 46 in humans. The chromosomes carry thousands of DNA units called genes, which contain the hereditary code. These codes cover physiological, biochemical and physiological traits of a person. For example, some genes govern the development of tissues and organs. Others govern certain traits such as straight or curly hair, colour vision and blood type. The expression of some traits in the new individual depends on how the parent’s genes interact. Some genes are dominant, while others are recessive.

The presence of one or two dominant genes results in expression of the dominant gene, for example, the gene for brown eyes in humans is dominant over the gene for blue eyes. To exhibit a recessive trait, such as blue eyes, both genes, one from each parent must be recessive.

Many characteristics are influenced by more than one gene. Skin colour, for example is controlled by several genes. Some characteristics depend on other inputs besides the genes. For example, although intelligence may be genetically influenced, it is also determined by environmental influences.

Sex-linked traits refer to those hereditary traits that are carried on the X chromosome, such as colour blindness. Genetic defects passed on by heredity from one generation to another are the cause of many human diseases and disorders many of which have been identified. Many genes that cause diseases have now been identified, allowing parents the option of genetic counselling and testing during pregnancy. Advances in DNA mapping and bionics, hold out the promise of eliminating or curing many hereditary diseases at a future date.

Ribonucleic acid (RNA):

 Ribonucleic acid (RNA) is one of the three major biological macromolecules that are essential for all known forms of life (along with DNA and proteins). The flow of genetic information in a cell takes place from DNA through RNA to the proteins. RNA, thus, are the work-horses of the cell and play leading roles in the cell as enzymes, structural composition, cell signalling etc.

DNA is considered the “blueprint” of the cell, which carries all the genetic information required for the cell to grow, take in nutrients and to propagate. RNA, in this role is the “DNA photocopy” of the cell. When the cell needs to produce a certain protein, it activates the protein’s gene – the portion of the DNA that codes for that protein – and produces multiple copies of that piece of DNA in the form of messenger RNA (mRNA). The multiple copies of mRNA are then used to translate the genetic code into protein through the action of the cell’s protein manufacturing machinery called the “ribosomes”.  Thus, RNA expands the quantity of a given protein that can be made at one time from one given gene, and it provides an important control point for regulating when and how much protein gets made.

Recent researches have revealed that RNA plays a more important role than was hitherto believed which was acting as a DNA photocopy (mRNA) and a genetic coupler between the genetic code and protein building blocks (tRNA), as well as, a structural component of ribosomes (rRNA). In recent years, however, it has been found that RNA can also act as enzymes, called “ribozymes” to speed up chemical reactions.

In several clinically important viruses, RNA, rather than DNA, carries the viral genetic information as was found in ancient early forms of life on Earth. RNA also plays an important role in regulating cellular processes – from cell division, differentiation and growth to cell aging and death. Defects in certain RNAs or the regulation of RNAs have led to several important human diseases, including heart diseases, cancer, etc.

Present Day:

For a million years or more, man’s evolution has been independent of his surroundings and his adaptability to any environment – even the hostile vacuum of space seems assured. However, today, he is ready to tip the balance of evolution and environment in a different way. He is now able to interfere directly with the processes established by his own evolution. He has acquired the ability to change the genetic inheritance/coding which make humans what they are. However, he needs to tread this path cautiously so as not to lead to regressive/harmful mutations and side-effects beyond his control. 

The 25 Euro Silver-Niobium coin titled “Evolution”:

  This path-blazing Silver-Niobium Coin is the most innovative coin in this Series. For the first time, two colours/shades of Niobium have been used on this coin–blue & green.  
                                  

On the Obverse of the Coin, symbolising the origin of Evolution as a whole, an image of the DNA molecule, (the double helix), also known as Deoxyribonucleic  Acid, is depicted as well as RNA (Ribonucleic acid) – both of which are the keys and fundamental to evolution.  Also shown on this face of the coin is a half-filled beaker, with the liquid contained therein bubbling, a microscope for studying samples on slides and a symbol of the Caduceus, which is symbolic of Medicine.

On the outer periphery is mentioned on top the name of the country “REPUBLIK OSTERREICH” (meaning, the “Republic of Austria”) and the year of issue “2014”. On the left periphery is mentioned the denomination of the coin “25 EURO” and on the lower to right periphery is mentioned the theme of the coin “EVOLUTION”.

On the Reverse of the Coin is depicted the history of human development and the diversity of life-forms brought about by evolution. On the outer silver ring starting from the bottom periphery clock-wise is depicted a DNA Double Helix. The DNA chain represents life itself which has diversified into a bird, the brightly coloured toucan represents life forms and their abundance in the air. The fish and the frog represent life in water and how life evolved into land-based creatures. The mushrooms, and a flower whorl are representative of a complex biological world which has evolved over the eons along with the plants and animals. The leaves represent trees and plants, vital to replenishing the oxygen content in the atmosphere through the process of photosynthesis, and a fish both of which are partially overlapping into the Niobium core/pill and a frog, representing amphibious life (both on land & water). In the inner Niobium core is shown the evolutionary cycle of the Homo Sapiens – the first Monkeys and Apes (who evolved during the Cainozoic Era, in the Tertiary Period in the Oligocene Epoch, 25 to 40 million years ago) to the first man-like Apes (who appeared in the Cainozoic Era in the Tertiary Period in the Pliocene Epoch, 2 to 10 million years ago) to the First true man, the Homo Erectus (who appeared in the Cainozoic Era in the Quarternary Period, Pleistocene Epoch, 10000 to 2 million years ago). Of course, the man depicted on this coin is well groomed & is like a 10.0 version of his ancestors. Air bubbles surround these elements, representing the key role played by oxygen in sustaining life.


Links:

1) The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: First Coin: "700 Years of Hall City in Tirol or Tyrol"

2) The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: Second Coin: "150 Years of Semmering Alpine Railway"

3) The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: Third Coin: "50 Years of Television in Austria" 

4) The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: Fourth Coin: "European Satellite Navigation System"

5) The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: Fifth Coin: "Austrian Aviators"

6) The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: Sixth Coin "Fascinating Light"

7) The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: Seventh Coin: " The International Year of Astronomy"

8) The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: Eighth Coin: "Renewable Energy"

9)The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: Ninth Coin: "Robotics"

10) The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: Tenth Coin: "Bionics"

11) The 25 Euro Silver-Niobium Coin Series issued by the Austrian Mint: Eleventh Coin: "Tunnel Construction"

12) The 50 Euro Gold Coin Series: Klimt and his Women: 2012-2016  (includes Coin of the Year 2015 (COTY)

9 comments:

  1. Ramchandra Lalingkar has commented:
    "Very interesting information about 'How physical development of a human being has taken place over a Billion Years period, beyond common belief of 'Only Human beings have "Developed" brain among other species in the nature. Thanks !"

    ReplyDelete
    Replies
    1. Thank you . As humans have inhabited the planet Earth for a "miniscule period' of time & have been "gifted" with a brain capable of rational thought, perhaps, it is more important for us not to harm it in any way and the imperative need to protect Earth’s resources for future generations of bio-diversified life forms.

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  2. Krishnayya Ramadana has commented:
    "Rajeev.....that how man whose species originated but 40,000 years ago manages to dominate over all the other animals on earth whose species are much older.... I find it very mysterious as to why that should be so......"

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    1. I guess, that, from the time that man's oldest direct ancestor "Ramapithecus" who evolved some 14 million years ago, to the first "modern man" (Homo Sapiens Sapiens - meaning "intelligent man") who has come to inhabit the Earth some 40000 years ago, the process of Natural Selection seemed to have been heavily loaded in favour of humans, who have come to take Nature's bounty for granted. The recently inconclusive Conference on climate change at Lima, Peru (in a long series of similarly inconclusive conferences during the past two decades) leads me to wonder, whether, we are really making use of the "rational thought" process that human brains are capable of or are irreparably damaging planet Earth for narrow-minded short term benefits!!

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    2. Ramchandra Lalingkar has commented:
      ".................whether, we are really making use of the "rational thought" process that human brains are capable of or are irreparably damaging planet Earth for narrow-minded short term benefits" - Absolutely correct observation. Mankind is 'SELFISH' and wants to use these resources for their own benefit, as if they are the only habitat of this earth. We are developing big cities encroaching on other species' right to live. Poor souls - where will they go? How will they survive?"

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    3. Sumita Chaudhry has commented:
      "I think the homo sapien is becoming the intelligent dinosaur, using up too much of the resources and will therefore end like the dinosaurs. So the so called 'intelligence' has not really served the homo sapiens. Maybe next time 'god' will get the mix right and be able to create something more sensible."

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    4. Perhaps it is time for us to sit back & ponder over how our actions today are going to impact future life forms on Earth.

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  3. Thanks for sharing this authentic update. Have you found any new value pick. When u might be posting your next gem. Checking your blog daily for your next pick.

    Micro Filtration | Ultra Filtration

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    1. Thank you, Angeline for visiting my blog & your encouraging comment. I have a post on a silver-niobium coin on the theme "Cosmos" which was released last year, still in the works. Still to check out this year's release. With around forty coins/banknotes/stamps to write on, I have fallen back on my writing schedules somewhat.

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