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Viktor Rebrik.
New theory of the geological history of Earth.
O Gaia!
Henri Volohonsky
It is known that the Earth was created about 4.5 billion years ago (more precisely from 4.6 till 4.45
billion years). Scientists divide the geological history of Earth into some main eras: Archaeus,
Proterozoic, Paleozoic, Mesozoic, Cenozoic. Such division does not give possibility to answer the
question: at what stage of its development is the Earth situated now? The postulated eras have not the
same length in the time. In difference to the accepted now, our classification divides the geological
history into cycles and periods, which have equal time length. For the simplicity we accept the initial
date of creation of Earth and Sun ca. 4.555(5)… billion years. Then we can postulate the following
cycles:
I.4.555(5)…-3.555(5)… billion years.
II.3.555(5)…-2.555(5)... billion years.
III.2.555(5)…-1.555(5)… billion years.
IV.1.555(5)…-0.555(5)… billion years.
V. 0.555(5)… billion years – till modern time.
For the simplicity, first four cycles can be divided into two sub-cycles half a billion years each. The
division of every cycle into 9 periods 111,1(1)… million years each is more precise.
Four cycles make together so called pre-Caembrium or the most ancient history of the Earth. The last,
5th cycle made now a bit more than a half of its development. It can also be divided into five periods
111,1(1)… billion years each. It is possible that after the end of the ice time the new, 6th period began,
which corresponds to Holocene, begun 11.5 thousand years ago. Metaphorically 100 million years
correspond to one year, i.e. the Earth is now about 45-46 years old (if we imagine it as a living creature,
as already the ancient thought). Let us look how our division corresponds to the reconstructed in the
present time geological history.
I cycle.
1 part of the first cycle corresponds to so called “pre-geological” stage of the planet’s existence, dated
4.5-4.0 billion years. It is so called “accretion period”, which lasted 100 billion years and corresponds to
the uterine development. In this time core, mantle, sub-divided into lower and upper, and possibly the
initial crust, which consisted from basalt, were created. Earth damaged from the strongest meteorite
bombarding, which caused its warming-up, creation of the initial atmosphere, hydrosphere, which were
different from modern ones, formation of the magmatic ocean in the upper part of the mantle. In the
same time the liquid core of Earth and the first basaltic Earth mantle were created. Probably the first
atmosphere had strong hothouse effect. Proto-atmosphere consisted from H2O, CO2, CH4, CO, H2S, SO2,
HCl and some other gases and combinations, which were partly dissolved in the initial chloride and
sulphateless hydrosphere, which had to be in equilibrium with atmosphere. The oldest fragment
materials circones (Western Australia) are dated with
4.3-4.2 billion years.
2nd part of the first cycle corresponds to the early Archaeus (4.0-3.5 billion years). In this time Earth
had almost all spheres, besides the inside core - the outside core, mantle, crust, atmosphere and
hydrosphere. The initial atmosphere could be like Venerian, temperature was much more than the
modern one. Presence of hydrosphere is confirmed with the aquatic presence of quartzites in the oldest
complex of Isua in Greenland. In it graphite is present, where the content of isotopes of 13С to 12С is
almost the same like in the modern organic remnants. At the expense of the melting of the
initial basaltic crust with participance of the fluids, which came from mantle, the siale isles –
proto-continents appeared, raising over the still very shallow water ocean. They were made
from the “grey gneises” – granitoides, which differed from the later “normal” granites with
prevalence of natrium over calium in its content. At the expense of washing out of this dry land
the first sedimental fragment rocks were created, discovered in Greenland and Canada (age 43.8 billion years). 3.8 billion years ago the first procariotes (microphossils) were created. In the same
time the meteorite bombarding ends and the Earth satellite Moon is created. In the whole this cycle
corresponds to the physical plane. The geological age of Earth corresponds to the age of child till ten
years.
II cycle.
The first part corresponds to the middle Archaeus ((3.5-3.0 billion years), the second – to the late
Archaeus (3.0-2.5 billion years). In the whole this cycle corresponds to the aethereal plane. Geological
age of the Earth corresponds to the teen-ager till 20 years.
Main geological events of this epoch:
3.5 billion – plausible remnants of the magnetic field, which did not differ from the modern.
3.2 billion – begin of the creation of the ripe continental crust.
3.0 billion – on the Earth the mechanism of lithosphere plates began to function.
In the end of Archaeus (2.7-2.5 billion years) stabilization of the continental crust began.
In this time the organic life is created. Its remnants are known in the old rocks of the Pilbara bloc (3.53.4 billion years) in the Western Australia, where remnants of the life activity of blue-green algae –
cyanophites (stromatolithes and oncolithes) are found. The microscopic creations – shells of the one cell
cyanophites (acritarches) and contractions from carbonates (katagraphias) are found. The first living
creatures were bacteria, changing inorganic combinations into organic ones, using the sun light. Bacteria
decomposed hydrogen sulphide, educing sulphur. Blue-green algae began to decompose water, educing
oxygen, and the ozone layer, which appeared in the upper layers of atmosphere, guarded organisms
from the deadly ultraviolet radiation, therefore they could exist already not only in the water, but also
on the dry land. In the rocks useful fossils are created. Among them there are iron, gold, copper, lead
and other metals and graphites.
III сycle.
This cycle corresponds to the early Proterozoicum (2.5-1.65 billion years). In the whole it corresponds to
the lower astral plane. In comparison with the human life it can be compared with the youth from 20 till
30 years.
Main geological events of the epoch:
2.5 billion years – creation of the supercontinent Pangaea-0, which contained from 60% till 80% of the
crust volume of modern continent. At the other side of the planet the even greater ocean – Panthalassa
had to oppose it; probably, it was created because of the fall of giant meteorite. The cover freezing
(Guron) takes place.
2.2 billion years – Pangaea-0 began to disintegrate with creation of basins with the crust of oceanic type.
2.0 billion years – in the atmosphere the presence of oxygen can be detected. The moving zones finish
their development.
1.8 billion years – creation of Pangaea-I (Rodinia).
In the course of early Proterozoicum the developmentof organic world was expressed in the broad
expansion of blue-green algae; the products of their live activity as lime films composed stromatolite
buildings, which reached the length of hundreds meters in some places (first stromatolites appeared in
the late Archaeus). The photosynthesis activity of theses algae caused the changing of atmosphere
composition with the increasing of oxygene in it, which stimulated the further flourishing of organic
world in its turn. It is not excluded that the educed oxygene, reacting with the iron, dissolved in the
water, promoted the precipitation of iron oxides, in the result of which the thick layers of the stripe iron
quartzites – jaspilites were formed. The procariote organisms – bacteria existed too. Early
Proterozoicum was a famous epoch of iron ore accumulation. The gold-uranium-pyrite conglomerates,
copper ores, as well as diamond and gold fields are formed (modern Africa).
IV cycle.
This cycle corresponds to the late Proterozoicum (Riphaeus) and Vend (1.650-540 million years). In the
whole it corresponds to the upper astral plane. In comparison with the human life it corresponds to the
period from 30 till 40 years.
The 1st part corresponds to the lower and middle Riphaeus (1.650-1.350, 1.350-1.000 billion years),the
2nd part – upper Riphaeus and Vend. The main events of the epoch:
1.4 billion years – emergence of the first eucariota (algae).
1.4-1.35 billion years – development of volcano plutonic zones, outbreak of granitoide magnetism.
0.8 billion years – disintegration of Pangaea-I; emergence of multicellar plants (algae);
0.67 billion years – emergence of the Vend skeletonless fauna (Ediacaria);
0.57 billion years – emergence of the skeletonless fauna of invertebrates.
V cycle.
This cycle corresponds to the Phanerozoic epoch. In the whole it corresponds to the lower mental plane
(animal world). In comparison with the human life it corresponds to the period from 40 from 46 years.
As we already mentioned before, the last, Vth cycle went through a bit than a half of its development.
One can divide it into five periods 111,1(1)… million years each. Probably, after the end of the last ice
time a new, 6th period began, which corresponds to Holocene, begun only 11.500 years ago.
1. 555,5 (5)… – 444,4(4)… million years.
This period corresponds clearly enough to geological Caembrium (542-488.3 million years) and
Ordovician (488.3 – 443.7 billion years).
Main events of this period:
0.56 billion years – quantity of oxygene in the atmosphere reaches 1/3 from normal.
0.46 billion years – first terrestrian plants appear.
0.45-0.43 billion years – first dying out of organisms.
Материки концентрировались преимущественно вблизи экватора, что и способствовало
установлению теплого климата, вероятно, вместе с усилением эксплозивного вулканизма.
The main event of the Caembrium was emergence and rapid flourishing of the varied fauna of
invertebrates, which had a mineral skeleton, emergence and domination of trilobites. It appeared at the
background of the domination of warm climate and broad spreading of the epicontinental seas. To the
begin of the period megacontinent Gondwana was formed and future northern continents – Laurentia,
Baltia, Siberia, Sinokorea were separated with the oceans, which continued to expand in Caembrium: in
the present time their crust is represented with ophiolithes.
Main features of the Ordovician period:
-preservation of Gondwana unity and the square of other continents with contemporary maximal
expansion of intercontinental oceans (Japetus, Paleothetis, Paleoasiatic) in the middle of period; in the
late Ordovician the Takon orogenesis appears, which causes the essential changes in the inside structure
of some moving zones, especially of the Paleoasiatic ocean;
-domination of the warm climate in the course of early and middle Ordovician, then rapid cooling and
emergence of the cover freezing in Gondwana and its periphery in the connection with moving of
Gondwana into the polar region of South ocean;
-further development of organic world with possible emergence of terrestrian plants. Emergence of seaurchins. Graptolithes played an important part in the Ordovician. Molluscs and jawless fishlike
organisms were spreaded broadly in Ordovician.
2. 444,4(4)… – 333,3(3)… million years.
This period corresponds to Silurian (443.7 - 416 million years), Devon (416-359.2 million years) and first
two layers of the Carbon period (Turnean – 359.2-345.3 million years and Vizean – 345.3- 326.4 million
years).
Main event:
0.42 billion years – emergence of fishes – first vertebrates.
Relatively small Silurian period looks like transitory between thalassocratic (i.e. with predominance) and
geocratic (i.e. with predominance of dry land) Devonian. In the begin of period on the west of
Gondwana glaciers, inherited from Silurian, were still preserved, but then climate became more and
more warm. Silurian period was remarkable with the closing of Japetus ocean, Tornquist sea and
reduction of square of central and eastern Paleothetis and Paleojapetic ocean and ended with epoch of
the mighty mountain creation, plication, granite magmatism and regional metamorphism. Although in
the composition of Silurian biota the same invertebrates like in Caembrium and Ordovician prevailed,
especially graptolithes, the emergence of vertebrates, among them the first fishes, and the first
terrestrian plants – lycopodia together with mosses and mushrooms, inhabiting the dry land, is
remarkable.
Devonian period was one of the turning-points of the Earth history. It closed early and began late
Paleozoicum. Frontier of Silurian and Devon corresponds with culmination of Caledonian orogenesis,
which created North Atlantic zone of caledonides, united Laurentia and Baltia and created new
megacontinent Laurentia. It was a first step to the creation of Pangaea-II. In the course of Devon period
the climate was warm and even hot, arid or wet. In the seas many crustacean, fishes, ammonoideae
emerged, on the dry land – luxuriant plants, including ferns. In the early Devon first wingless insects
emerged, in the end – first amphibian were created.
3. 333,3(3)… – 222,2(2)… million years.
Period corresponds to Carbon (359.2-299 million years), Perm (299-251 mln. years) periods of
Paleozoicum and lower and middle Trias (251-228 million years).
Main events:
0.25 billion years – emergence of hymnospermae plants
0.24 billion years – creation of Pangaea-II, mass effusions of basalts.
In the early carbon the warm climate dominated everywhere, seas had broad diffusion. In the second
part of Carbon the creation of one Pangaea-II took place because of the collision of the Western
Gondwana with Laurussia in the region of south of North America and Western Mediterranean. The
giant cover freezing, which encircled Gondwana, was created. The domination of warm and wet climate
out of the freezing region created conditions for the luxuriant development of different wood plants and
for the creation of vast zone of coal accumulation (possibly, because of the mighty hurricanes).
Development of the animal world: amphibia, reptilia and insects were created.
To the begin of Perm in the whole the genesis of Pangaea-II was finished, Baltia, Kazakhstan and Siberia
united, one Laurasia was formed. Cover freezing of Gondwana degraded gradually, glacial sediments
were succeeded with carboniferous, then with red colour thick layers. The tin (Cornwall, England) and
mercury (Nikitovskoye) deposits appeared. In the whole for the Perm period very contrast climatic
conditions are typical, it was closed with the extinction of many groups of Paleozoic fauna.
In Trias the existing of one Pangaea-II and one Gondwana as its part ends, but not fully. Warm, even hot
climate is preserved. In the begin of the period the organic world has a transitory character from
Paleozoicum, but generally it has changes. In the sea the ammonoideae, six beam corals, on the dry land
reptilian are created. First dinosaurs emerged.
4. 222,2(2)… – 111,1(1)… million years.
Period corresponds to the upper Trias (228-199.6 million years), Jurassic (199.6-145.5 million)
and lower Cretaceous period till Alb layer (145.5-112 million years).
In the upper Trias rifts in the North Atlantic are opened, first mammals are created.
Jurassic period was characterized with the begin of disintegration of last Pangaea-II, among it
Gondwana, and creation of Atlantic and Pacific Ocean – 0.16 billion years. In the end of middle Jura
ocean Thetis with its continuation into Central Atlantics and Mexican-Caribic region separated Laurasia
from Gondwana fully. In the begin of Jurassic period the early Lamirian orogenesis , manifested in Eatern
and South-East Asia, in the end – late Lamirian, manifested in the Pacific circle of moving zones, takes
place. In the Jura sediments about 16% of world coal reserves are preserved.In the course of all period
climate remained warm and mostly wet. Among the sea fauna ammonites predominated, among the
dry land one the domination of dinosaurs began, meanwhile the sea were explored by the big pangolins
– plesiosaurs, ikhtiosaurs. In the late Jura the first birds were created. In Early Cretaceous period big
foraminipherae – orbitolithes emerge. Gondwana is disintegrated, South Atlantics is created. In the
begin of Cretaceous period the late Cimmerian orogenesis takes place.
5 period -111,1(1)... mln. – 11,500 BP.
To this period the Late Cretaceous, Paleogene, Neogene and Quarternary periods belong. The
continents took their today´s shape slowly. About 68 million years ago. They have almost today´s shape,
but India is an independent continent and Arabia is connected with Africa. Reptiles (Dinosaurs)
dominated on the Earth. Flowering plants (angiosperms) diversified during the Cretaceous, but
remained a minor contributor to plant biomass and ecosystem function until after the End Cretaceous
extinction. The earliest probable grass phytoliths have been found in fossilized dinosaurs dung from the
latest Cretaceous, just before 65 million ago. Mammals were also quietly evolving throughout the
Cretaceous. The first termite body fossiles also came from the Late Triassic. By the start of the Late
Cretaceous (100-90 million years ago) both fossils and molecular clocks agree that some of the main
“crown” mammal lineages had already diverged (eutherian or placental mammals had already arisen by
125 million years ago). But the Mesozoic mammals could not challenge the smaller brained dinosaurs
for ecological dominance.
65 millions years ago the End Cretaceous extinction, which famously killed off the dinosaurs,
took place. It marks the transition from the Mesozoic to the Cenozoic Era. A thin sedimentary layer
enriched in the element iridium at the boundary of the Cretaceous and Paleogene periods provides
convincing evidence that a massive asteroid (asteroid) hit the planet. The vast volcanic flood basalts –
the Deccan traps – erupted over less than a mllion years leading up to the boundary. There is also some
evidence of ocean anoxia of the End Cretaceous. The Cretaceous mass extinction impacted land as well
as marine life. There were widespread wildfires at the boundary and vegetation was decimated by
global deforestation. In the aftermath there was a brief flourishing of fungi feeding on decaying plant
material (saprotrophs), then ferns colonized the land. Terrestrial ecosystems than recovered to
something approximating their pre-extinction state much faster than marine ecosystems (which took
around three million years). Land animals suffered remarkably selective extinctions. Insect diversity had
been high beforehand but was still low nearly two million years after, probably because of the
temporary loss of plants. Verterbrates that could retreat to the water including amphibians, turtles,
snakes, lizards and crocodiles all faired reasonably well. In the air, the last Pterosaurs died out but birds
largely survived. All major mammal lineages survived (including egg laying monotremes, marsupials and
placentals) although they suffered losses. Cretaceous mammals were generally small in size, comparable
to that of rats, and may have burrowed or lived partly in water. In general among land animals,
omnivores fared well, whereas pure carnivores or herbivores suffered.
After the End Cretaceous extinction, mammals came to fill many of the ecological niches vacated
by the dinosaurs. They increased in the size within one million from the boundary. That was
accompanied by striking species diversification in the best preserved continental fossil record from
North America. Hovewer, this diversification, in the Paleocene Epoch, was mostly among groups of
mammals that have subsequently declined or gone extinct. Rodents may have diverged from other
placental mammals in the Paleocene. Grass pollen then starts to appears from about 60 million years
ago. Hovewer, the modern orders of placental mammals did not originate until ten million years after
the End Cretacous. The three key orders that emerged then were the Primates (to which we belong), the
even-toed ungulates (Artiodactyla), and the odd-toed ungulates (Perissodactyla). All these orders
appeared in a remarkable time of climatic upheaval called the Paleocene-Eocene Thermal Maximum
(“PETM”). It was an interval of rapid global warming 55.8 million years ago. Global temperatures rose
roughly 5°C within 20 000 years and remained high for roughly 100 000 years. There was also a major
perturbation of the carbon cycle, whic occurred in two steps, each lasting roughly 1000 years and
separated by 20 000 years. The trigger may have been a volcanic intrusion into carbon-rich sediments
under the North Atlantic. Methane released would have been rapidly oxidized to carbon dioxide,
contributing to warming and ocean acidification. Acidification in turn dissolved carbonate sediments in
the deep ocean and caused the extinction of many calcareous-shelled organisms living there. It took
around 100 000 years for the carbon cycle to recover. During the PETM, the modern orders of mammals
appeared within 10 000 years or so of each other in North America, Europe and Asia. Primates were the
last of the three orders to arrive roughly 10 000 years into the event. The earliest species were
significantly smaller than their immediate descendants. This dwarfism could be due to poor plant food
quality in a carbon dioxide rich world. The early part of the PETM was dominated by small leaved plants
indicative of a dry climate. Later in the PETM the climate became wetter. The first unequivocal fossil
parts of grass plants appear 55 million years ago. The contact between Australia and the Antarctis was
lost 56 million years ago.
An overall driver for the spread of grasslands was a cooling and drying of the climate over the
last 50 million years, which in turn was probably driven by declining carbon dioxide concentration. The
steady trend was interrupted by a relatively rapid cooling and drying of the climate 33.7 mln years ago,
which marks the boundary between the Eocene and Oligocene Epochs of the Paleogene Period. This
occurred when atmospheric carbon dioxide and temperature passed a critical threshold triggering the
rapid growth of large ice sheets on the continent of Antarctica. It in turn triggered the first phase of
grassland expansion, at the mid-latitudes became cooler and drier and the first desert grasslands
replaced earlier woodland in the Great Plans of North America. The soils undernearth the grasses
experienced an increased intensity of silicate weathering, which would have contributed somewhat to
declining cron dioxide and global cooling.
The second phase of grassland expansion began around 17 million years ago, early in the
Miocene Epoch. Short grasses appeared forming a sod, or natural carpet, with more organic-rich soils
beneath them. Such grasslands are effective at chocking out the seedlings of woody plants and
promoting the spread of fire; charcoal becomes more abundant in he rock record record at the time.
Grazing hoofed mammals (ungulates) expanded with the grasslands, having specially adapted
(hypsodont) teeth to grind down the silica-rich grass matter. There was an explosive adaptive radiation
of horses and antelope, along with many other mammals adapted to feeding on grasses and living in
grasslands. Increased weathering led to increased inputs of phosphorus and silicon to he ocean and
increased burial of them in marine sediments, and conceivably contributed to a resumption of climate
cooling and Antarctic glaciation. The presence of grass rather than trees would have increased the
reflectivity of the land surface, tending to cool the continental interiors and increase their seasonity.
The third phase of grassland expansion occurred late in in the Miocene, beginning around seven
million years ago. Tall grasses forming a sod appeared with deep soils under them. They expanded into
more humid regions, promoting fire as they displaced forests, again recorded by increased charcoal in
the rock record. During this phase, a mecanism of concentration carbon dioxide at the side of carbon
fixation within the plant, called “C4 metabolism”, proliferated among the grasses. (C4 plants were
already present by about 15 million years ago, but between 7 and 5 years ago they underwent a marked
expansion in the tropics). The expansion of these grasses caused another pulse of increased weathering
and phosphorus and carbon burial in the ocean.
The pliocene spans 5.3-1.8 million years ago.
In the newly created world of mixed grassland and trees, around six million years ago, our own
lineage Hominids (which currently includes five genera: Ardipithecus, Australopitecus, Praeanthropus,
Paranthropus and Homo) appeared. Chimpanzees (Pan), which are anatomically close, also appeared in
this time. The first hominid fossils date between 5.8 and 4.4 million years ago and have been assigned to
the genus Ardipithecus. They may have lived in shady forest. Between about 3.9 and 3 million years,
members of the genus Australopithecus were widespread in Eastern and North Africa. The first
footprints of upright hominids walking on two legs are preserved in 3.7 million year old volcanic ash
(from Laetoli in Tanzania). As hominids took their first, faltering steps, the long cooling trend was
triggering the start of the Earth´s climate instability. The first stone tool use is recorded 2.6 million years
ago. Between 2.2 and and 1.6 million years ago, Homo habilis (probably better reclassified as a member
of the Australopithecus genus), were using stone flakes as tools, such as for claving meat off carrion. But
they did not master the use of tools in hunting or defense, and were regularly preyed by large
carnivorous cats.
Our genus, Homo, originated in the Great Rift Valley of East Africa, roughly two million years
ago, during the relatively mild climate of the Pliocene Epoch. Homo erectus was the first undisputed
member of our genus, with improved long distance walking and running ability. Homo erectus formed
the first hunter-gatherer societies. When Northern Hemisphere ice ages began in earnest 1.8 million
years ago (making the transition from the Pliocene to Pleistocene Epoch), a wet phase of African climate
provided a corridor of familiar savannah habitat through which is currently a part of the Sahara desert.
This allowed Homo erectus to make a relatively easy exit from East Africa, and they spread widely, both
eastwards to Indonesia (Java) and China, and north-west to North Africa and Europe (Georgia). From this
dispersed populations of Homo erectus, multiple hominid species appear to have evolved. These include
Homo antecessor in southern Europe around 800 000 years ago and Homo heidelbergensis in central
and northern Europe around 500 000 years ago. The heavily built Neanderthals (Homo
neanderthalensis) may have evolved from Homo heidelbergensis in Europe, whilst the origins of tiny
Homo florensiensis (from Flores, Indonesia) are currently being argued over (they may be a case of
island dwarfism, descended from Homo erectus, although some of their features are more primitive).
Homo erectus may have developed a form of “proto-language” as they formed larger larger social
groups and their brain size increased. Early Homo transported stone for tool making up to 13 km, but
after 1.2 million years ago, raw materials were transported greater distances of up to 100 km. It was
Homo erectus that learnt to control fire. The controlled use of fire may date back as early as 1.5 million
years ago, and evidence of its use for domestic purposes such as heating and cooking is scattered
through the Pleistocene. By 800 000 years ago, hominids have learnt to create fire. Stone tool
technologies also became more elaborate between about 400 000 and 250 000 years and brain size
increased.
The stone age is divided in three periods: 600-100 BCE Old stone age; 100-50 BCE Middle stone
age and 50-10 BCE New stone age. The glacial times were changed with interglacial:
600-540 1st ice time (Günz);
540-480 1st warm time (Günz-Mindel);
480-430 2nd ice time (Mindel);
430-240 2nd warm time (Mindel-Riß);
240-180 3rd ice time (Riß);
180-120 3rd warm time (Riß-Würm);
120-10 4th ice time (Würm).
Homo sapiens originated in East Africa around 200 000 ago, when the high Northern latitudes
were in the grip of the penultimate ice age and Africa was particularly arid. The first fossils of
anatomically modern humans come from Ethiopia. “Mitochondrial Eve” lived around 160 000 years ago.
By around 100 000 years Homo sapiens had spread throughout Africa and into the Middle East (120 000
years ago he is present in Palestine), but other Homo species were still much more widespread, and
Homo erectus, Homo neanderthalensis and Homo floresiensis all survived until remarkably recently
during the last ice age. The FOXP2 gene, which is involved in speech and language, was fixed in the
human population sometime during the last 200 000 years. Then by 130 000 years ago in Africa, raw
materials for stone tool making were being transferred up to 300 km, beyond the range of any one
group. Our ancestors emerged out of Africa and the Middle East and began to spread around the world
around 65 000 years ago. The migration may have been facilitated by one of the periodic wet phases of
the Sahara after a mega-drought in Africa from 135 000 to 90 000 years ago. The latest evidence
suggests that modern humans first went East along a Southern coastal route through India and onward
to Southern Asia and Australasia. An early offshoot from this migration led ultimately to the colonization
of the Near East and Europe, but was stalled by unfavourable climate conditions in the lands bordering
the Eastern shores of the Mediterranean, known as the Levant. Around 50 000 years ago technology
became more sophisticated with the development of bone and antler tools, hunting became more
specialized, long distance trade began, pigments were processed and artwork appeared, then our
ancestors began ritually burying their dead. At some point during that interval, the ancestors of all of us
humans alive today experienced a bottleneck in population of 10 000 or fewer breeding pairs. Members
of this founding group have gone on to dominance. As modern humans arrived in new continents, many
large mammal genera (over 40 kg) began to go extinct. Modern humans arrived in Australia sometime
between 72 000 and 44 000 years and 14 of 16 genera went extinct. They reached Europe over 30 000
years ago where 9 of 25 genera went extinct.
In the whole, in this period the life developed modern forms: angiosperms and mammals became
predominating on the Earth, at the end of period humans appear.
VIth period – 11 500 years ago till now.
Human societies have flourished during the Holocene Epoch, the current interglacial (warm period
between ice ages) that started around 11 500 years ago.
Modern humans reached North America 11 500 years ago where 33 of 48 genera went extinct, and they
continued to South America by 10 000 years ago where 50 of 60 genera went extinct. Our ancestors
clearly played a part in these extinction. Extinction was less severe in Africa (8 of 44 genera).
Prior to the Holocene, abundant wild cereals were being collected, pounded and ground for food by
members of the Natufian culture in the Levant. Then, perhaps in response to the drying effects of the
Younger Dryas cooling 12 900 to 11 600 years ago on their regional ecosystem, people in this region
domestical the first cereal crops, triggering the Neolithic revolution (12 000 to 10 000 years ago). Early in
the Holocene, around 10 500 years, the Sahara re-entered one in its wet and green phases and the
region encompassing the Nile, Euphrates and Tigres rivers, connected by the Levant, became the fabled
Fertile Crescent. Farming arose independently in a number of other locations during the Holocene. Rice
was domesticated in China, as early as 11 500 years ago. Maize (a C4) was domesticated somewhere in
Mesoamerica, sometime before 7 000 years. The Andes and Amasonia, eastern North America, Sahel,
tropical West Africa, Ethiopia, and New Guinea were also centres of domestication. Around 5000 years
ago, a large scale climate change involving the drying and collapse of savannah ecosystems in the
Sahara, brought a 200 year period of drought to the Middle East. Then the wetter conditions returned,
but further interval of drought was about 4200 ago.
See also our “History of the world civilisation” Vol.1 §7 “Pre-civilisations”.
How many years will the Earth exist? We see that it is now in the 6th period of the Vth cycle, which
corresponds to the age of 45-46 years. Vth cycle corresponds to the lower mental plane, VIth – to the
higher mental plane (causal), VIIth – to the lower intuitive plane, VIIIth – to the higher intuitive plane,
IXth – to the spiritual plane. So the Earth is now approximately in the middle of its existence and will
exist 9 billion years in the whole (which corresponds to 90 years), if God will.
Literature.
Richard Dawkins, Geschichten vom Ursprung des Lebens. 2. Aufl. Ullstein, Berlin 2010.
Tim Lenton and Andrew Watson, Revolutions that made the Earth, Oxford University Press, Oxford
2011.
Günther A. Wagner, Age Determination of Young Rocks and Artifacts, Springer-Verlag Berlin Heidelberg,
1998.
Г.А.Вагнер, Научные методы датирования в геологии, археологии и истории, Москва, Техносфера
2006.
Н.В.Короновский, В.Э.Хаин, Н.А.Ясаманов, Историческая геология, 2-е изд., М., «Академкнига»,
2006.