Many of the world’s cultures seem to be drying out after massive flooding.

The Holocene Impact Working Group is a group of scientists from Australia, France, Ireland, Russia, and the USA who hypothesize that meteorite impacts on Earth are more common than previously supposed.

The group posits one large impact (equivalent to a ten-megaton bomb) every thousand years.

This estimate is based on evidence of five to ten large impact events in the last ten thousand years.

Satellite observations suggest the presence of many recent impact craters; megatsunamis are thought to have caused landforms such as chevrons.

The chevrons often point in the direction of specific impact craters, the supposition being that the chevrons were deposited by tsunamis originating from the impacts that formed those craters.

Burckle Crater is an undersea crater the Holocene Impact Working Group considered likely to have been formed by a very large scale and relatively recent (c. 3000-2800 BCE) comet or meteorite impact event.

It is estimated to be about thirty kilometers (eighteen miles) in diameter, hence about twenty-five times larger than Meteor Crater.

It is located to the east of Madagascar and west of Western Australia in the southern Indian Ocean, twelve thousand five hundred feet (thirty-eight hundred meters) below the surface.

Its position was determined in 2006 by the same group using evidence of its existence from prehistoric chevron dune formations in Australia and Madagascar that allowed them to triangulate its location.

Geologist Jody Bourgeois has challenged the theory that these chevron dunes are due to tsunamis; using a computer model to simulate a tsunami, she believes the structures are more consistent with aeolian processes.

Kumarikandam, a vast continent that joined Madagascar, Southern India, and Australia, is said to have existed here as per ancient Tamil literature.

Numerous ancient writings from various cultures refer to a "great flood.”

It has been hypothesized that these legends may be associated with this event.

This time period sees the Indus Valley Civilization and the end of its Early Harappan Ravi Phase at ca. 2800 BCE; it also sees the end of the pre-dynastic "antediluvian" rulers of the Sumerian civilization and the start of the First Dynasty of Kish after 2900 BCE. ("After the flood had swept over, and the kingship had descended from heaven, the kingship was in Kish.").

The pre-Xia dynasty rule of the Three Sovereigns and Five Emperors of China begins around 2850 BCE (with the first two figures, Fuxi and Nuwa, as husband and wife credited with being the ancestors of humankind after a devastating flood).

In Chinese mythology, the Yan emperor, Shennong, besides having taught humans the plow and basic agriculture, and been a god of the burning wind, was sometimes said to be a progenitor or minister of Chi You; and, like him, “ox-headed, sharp-horned, bronze-foreheaded, and iron-skulled”.

One difference between mythology and science is exemplified in Chinese mythology: Shennong and Huangdi, the Yellow Emperor, were supposedly friends and fellow scholars, despite the five hundred years or seventeen or eight generations between the first Shennong and Huangdi, and that together they shared the alchemical secrets of medicine, immortality, and making gold.

According to Sima Zhen's commentary to the Shiji, he is a relative of the Yellow Emperor and is said to be a patriarch of the Chinese.

The Han Chinese regarded them both as their joint ancestors.

Shennong cannot be said to be a historical figure.

However, Shennong, individual and clan, are very important, in the history of culture—especially in regards to mythology and popular culture.

Indeed, Shennong figures extensively in historical literature.

Even Sima Qian, regarded as the father of Chinese historiography, mentions that the rulers directly preceding the Yellow Emperor were of the house, or societal group, of Shennong.

Sima Zhen, who added a prologue for the Shiji, says his surname was Jiang and proceeded to list his successors.

An older, and today evidently more globally popular reference is in the Huainanzi: this is the famous one that says how before Shennong people were sickly and wanting, starved and diseased; but, that he taught them agriculture, which he researched himself, eating hundreds of plants, indeed, in one day even consuming seventy poisons.

Shennong also features in the book popularly known in English as I Ching, in which he is referenced as coming to power at the end of house Paoxi/Fuxi, inventing a bent-wood plow, a cut-wood rake, teaching these skills to others, and establishing a noonday market.

Another reference is in the Lüshi Chunqiu, mentioning some violence concerning the rise of Shennong, and that Shennong power lasted seventeen generations.

There are various subsequent notices of Shennong.

For example, Anthony Christie's Chinese Mythology references Shennong (as Shen-nung) six times, three times with pictures, according to the 1968 index.

The most well-known work attributed to Shennong is The Divine Farmer's Herb-Root Classic—first compiled some time during the end of the Western Han Dynasty, several thousand years after Shennong existed—which lists the various medical herb, such as lingzhi, which were discovered by Shennong and given grade and rarity ratings.

This work, considered the earliest Chinese pharmacopoeia, includes three hundred and sixty-five medicines derived from minerals, plants, and animals.

Shennong is credited with identifying hundreds of medical (and poisonous) herbs by personally testing their properties, which was crucial to the development of Traditional Chinese medicine.

Legend has it that Shennong had a transparent body and thus could see the effects of different plants and herbs on himself, and that in 2737 BCE, he first tasted tea from tea leaves on burning tea twigs, which were carried up from the fire by the hot air, and landed in his cauldron of boiling water.

Venerated as the Father of Chinese medicine, Shennong is also believed to have introduced the technique of acupuncture.

Shennong is said to have played a part in the creation of the Guqin musical instrument, together with Fu Xi and the Yellow Emperor.

Lesbos, near the Hellespont trade routes (modern Dardanelles), long has had strategic and commercial importance.

The oldest artifacts found on the island date to the Paleolithic period.

Important archaeological sites on the island are the Neolithic cave of Kagiani, probably a refuge for shepherds, the Neolithic settlement of Chalakies, and the extensive habitation of Thérmi (3000–1000 BCE).

In 1929-33, the British School excavated Thérmi, north of Mytilene, and Antissa, both important early Bronze Age (c. 3000-2750 BCE) towns.

Thérmi apparently was settled by Troas, judging from its Troy I-like black pottery.)

The largest habitation is found in Lisvori (2800–1900 BCE) part of which is now submerged in shallow coastal waters.

Toward the end of the Cucuteni-Trypillian culture's existence (from roughly 3000 BCE to 2750 BCE), copper traded from other societies (notably, from the Balkans) begins to appear throughout the region, and members of the Cucuteni-Trypillian culture begin to acquire skills necessary to use it to create various items.

Along with the raw copper ore, finished copper tools, hunting weapons and other artifacts are also brought in from other cultures.

This marks the transition from the Neolithic to the Eneolithic, also known as the Chalcolithic or Copper Age.

Bronze artifacts begin to show up in archaeological sites toward the very end of the culture.

The more complex trade network of the Proto-Indo-European culture, which would eventually replace the Cucuteni-Trypillian culture, supplanted the primitive trade network of this society, which had been slowly growing more complex.

The late period of the Cucuteni-Trypillian culture has witnessed a very dramatic shift in world climate.

For the entire duration of this culture's history, the earth has been going through what paleoclimatologists have called the Holocene climatic optimum, which lasted from 7000 to 3200 BCE.

During this time, the earth was both warmer and wetter than it has been at any time since the end of the last Ice Age, making conditions optimal for growing crops.

However, beginning around 3200 BCE, the Earth's climate began to become significantly more arid and cool.

This results in the Sub-Boreal phase, which creates the worst and longest drought in Europe since the end of the last Ice Age.

It also is the point when the region in North Africa that had been a land of forests and grassy plains is turned into the largest desert in the world.

This must have had a tremendous effect on the Cucuteni-Trypillian culture, which relies entirely on subsistence farming to feed the enormous populations in their massive settlements.

Without resources to feed their people, this culture would most certainly collapse, and there is much speculation among scholars that if this was not the most significant factor in this culture's demise, that it played an absolutely critical role in bringing it about.

Mari (present Tell Hariri), an ancient Sumerian and Amorite city situated on the western bank of Euphrates river seven miles (eleven kilometers) northwest of Abu Kemal, Syria, is thought to have been inhabited since the fifth millennium BCE, although it flourishes with series of superimposed palaces that spans a thousand years, beginning in 2900 BCE.

The city is strategically important as a relay point between the Sumerian cities of lower Mesopotamia, and the cities of northern Syria.

Sumer requires building materials such as timber and stone from northern Syria, and these materials have to go through Mari to reach Sumer.

Uruk III reaches up to 3000 BCE and into the Early Dynastic period (not to be confused with the Ur III period of the twenty-first century BCE, where the numbering refers to royal dynasties, not archaeological layers)The famous Uruk Vase (found in a deposit of cult objects of the Uruk III period) depicts a row of naked men carrying various objects, bowls, vessels, and baskets of farm produce, and bringing sheep and goats, to a female figure facing the ruler.

This figure was ornately dressed for a divine marriage, and attended by a servant.

The female figure holds the symbol of the two twisted reeds of the doorpost, signifying Inanna behind her, while the male figure holds a box and stack of bowls, the later cuneiform sign signifying En, or high priest of the temple.

Especially in the Uruk period, the symbol of a ring-headed doorpost is associated with Inanna.

Kish, occupied beginning in the Jemdet Nasr period, gains prominence as one of the preeminent powers in the region during the early dynastic period.

In the possibly mythical pre-dynastic period, the Sumerian king list portrays the passage of power from Eridu to Shuruppak in the south, until a flood occurred, from where it relocated to the northern city of Kish at the start of the Early Dynastic period.

It would then pass back to Uruk, Ur, and Lagash until the Akkadians overtook the area.

The twelfth king of Kish appearing on the list, Etana, is noted as "the shepherd, who ascended to heaven and consolidated all the foreign countries.” Although his reign has yet to be archaeologically attested, his name is found in later legendary tablets, and Etana is sometimes regarded as the first king and founder of Kish himself.

Archaeologists have confirmed the presence of a widespread layer of riverine silt deposits, shortly after the Piora oscillation, interrupting the sequence of settlement, that left a few feet of yellow sediment in the cities of Shuruppak and Uruk and extended as far north as Kish.

The polychrome pottery characteristic of the Jemdet Nasr period (3100–2900 BCE) below the sediment layer was followed by Early Dynastic I artifacts above the sediment layer.

The Sumerian king list states that it was the first city to have kings following the deluge, beginning with Jushur.

Jushur's successor is called Kullassina-bel, but this is actually a sentence in Akkadian meaning "All of them were lord.” Thus, some scholars have suggested that this may have been intended to signify the absence of a central authority in Kish for a time.

The names of the next nine kings of Kish preceding Etana are all Akkadian words for animals, e.g., Zuqaqip "scorpion.” The Semitic nature of these and other early names associated with Kish reveals that its population had a strong Semitic component from the dawn of recorded history.

Akkadian, a now-extinct Semitic language (part of the greater Afroasiatic language family) that was spoken in ancient Mesopotamia, is first attested in Sumerian texts in proper names from around 2800 BCE.

Eridu—associated with Enki (EA), god of the waters that are essential to the fishing and irrigation-based agricultural economy of its inhabitants and possibly linked to the sea by waterways—has by 2900 grown into a substantial city of mud-brick and reed houses, covering twenty to twenty-five acres (eight to ten hectares).

Peoples of Mesopotamia worship nature gods in human form: each god is associated with a city temple and the temples themselves occupy a central place in city life.

A typical Mesopotamian temple of the period, 2900—2800, has a facade decorated with niches dedicated to the cult of the god Enki.

The main temple to Enki is called E-abzu, meaning "abzu temple" (also E-en-gur-a, meaning "house of the subterranean waters""), a ziggurat temple surrounded by Euphratean marshlands near the ancient Persian Gulf coastline at Eridu.

He is the keeper of the divine powers called Me, the gifts of civilization.

His image is a double-helix snake, very similar to the Rod of Asclepius used to symbolize medicine or the Caduceus.

Considered the master shaper of the world, god of wisdom and of all magic, Enki is characterized as the lord of the Abzu (Apsu in Akkadian), the freshwater sea or groundwater located within the earth.

According to Sumerian mythology, Enki also assisted humanity to survive the Deluge designed to kill them.

In the Legend of Atrahasis, Enlil, the king of the gods, sets out to eliminate humanity, the noise of whose mating is offensive to his ears.

He successively sends drought, famine, and plague to eliminate humanity, but Enki thwarts his half-brother's plans by teaching Atrahasis about irrigation, granaries, and medicine.

Humans again proliferate a fourth time.

Enraged, Enlil convenes a council of deities and gets them to promise not to tell humankind that he plans their total annihilation.

Enki does not tell Atrahasis, but instead tells the walls of Atrahasis' (a.k.a.

Utnapishtim or Ziusudra) reed hut of Enlil's plan, thus covertly rescuing Atrahasis by either instructing him to build some kind of a boat for his family, or by bringing him into the heavens in a magic boat.

After the seven day Deluge, the flood hero frees a swallow, a raven, and a dove in an effort to find if the flood waters have receded.

On the boat landing, a sacrifice is organized to the gods.

Enlil is angry his will has been thwarted yet again, and Enki is named as the culprit.

As the god of what we would call ecology, Enki explains that Enlil is unfair to punish the guiltless Atrahasis for the sins of his fellows, and secures a promise that the gods will not eliminate humankind if they practice birth control and live within the means of the natural world.

The threat is made, however, that if humans do not honor their side of the covenant the gods will be free to wreak havoc once again.

This is apparently the oldest of the surviving Middle Eastern Deluge myths.

The cities of Sumer in the lower valley of the Euphrates River control Mesopotamia during the early third millennium; the cities themselves have by 2900 BCE come to be ruled by hereditary kings.

According to one theory, early Dynastic Sumer is governed by a league of cities that meet in the religious center of Nippur, near modern Baghdad, to decide issues democratically.

Other major cities of the period include Bad-tibira, Eridu, Kish, Larsa, Shuruppak, Sippar, Umma, Uruk, and Ur.

The Dynastic period begins ca.

2900 BCE and includes such legendary figures as Enmerkar and Gilgamesh—who are supposed to have reigned shortly before the historic record opens ca.

2700 BCE, when the now deciphered syllabic writing started to develop from the early pictograms.

The center of Sumerian culture remains in southern Mesopotamia, even though rulers soon begin expanding into neighboring areas, and neighboring Semitic groups adopt much of Sumerian culture for their own.

The Mesopotamian Bronze Age begins at about 2900 BCE.

The discovery of bronze enables people to create metal objects which are better than was previously possible.

Human habitation of the Qatar Peninsula dates as far back as fifty thousand years back, when small groups of Stone Age inhabitants built coastal encampments, settlements, and sites for working flint, according to archaeological evidences.

Other finds have included pottery from the Al Ubaid culture of Mesopotamia and northern Arabia (ca. 5000 BCE), rock carvings, and burial mounds.

The Qatar Peninsula was close enough to the Dilmun civilization (ca. 3000 to 2000 BCE) in Bahrain to have felt its influence.

A harsh climate, lack of resources, and frequent periods of conflict, however, seem to have made it inevitable that no settlement would develop and prosper for any significant length of time before the discovery of oil.