Geography

We are Hominids, or Hominidae, also known as great apes.

Our taxonomic family of primates includes four extant genera: the chimpanzees (Pan) with two species; gorillas (Gorilla) with two species; humans (Homo) with one species; and orangutans (Pongo) with two species.

Homininae, a subfamily of Hominidae that includes members of hominini—humans, as well as gorillas, chimpanzees, bonobos and some extinct relatives—comprises all hominids that arose after the split from orangutans (Ponginae).

A number of known extinct genera are grouped with humans in the Homininae subfamily, others with orangutans in the Ponginae subfamily.

The most recent common ancestor of the Hominidae lived roughly fourteen million years ago, when the ancestors of the orangutans speciated from the ancestors of the other three genera.

The subtribe Hominina is the "human" branch, including the genus Homo, which has its beginnings in this eon, which spans a quarter of a million years.

The fossil record suggests that individuals of the species Gigantopithecus blacki are the largest apes that ever lived, standing up to three meters (nine point eight feet feet) and weighing up to five hundred and forty kilograms (one thousand one hundred and ninety pounds).

Gigantopithecus, having come into existence perhaps nine million years ago, exists to as recently one hundred thousand years ago in what is now Nepal, China, India, and Vietnam.

This places Gigantopithecus in the same time frame and geographical location as several hominin species.

In addition to the Homo genus to which we belong, other members of the family include Orrorin, Ardipithecus, Kenyanthropus, and the australopithecines Australopithecus and Paranthropus.

The name of the genus Orrorin means "original man" in Tugen, and the name of the only classified species, O. tugenensis, derives from Tugen Hills in Kenya, where the first fossil was found in 2000, followed by another score or so more in the ensuing years.

Apparently a climber of trees, Orrorin lives in dry evergreen forest environment estimated at six point one million to five point seven million years ago (Mya).

If Orrorin proves to be a direct human ancestor, then australopithecines such as Australopithecus afarensis ("Lucy") may be considered a side branch of the hominid family tree: Orrorin is both earlier, by almost three million years, and more similar to modern humans than is A. afarensis.

The relationship of the Ardipithecus genus to human ancestors, and whether it is a hominin, or not, is unknown.

The literature describes two species: A. kadabba, dated to approximately five point sixmillion years ago (late Miocene), and A. ramidus, which lived about four point four million years ago during the early Pliocene.

Like most hominids, but unlike all previously recognized hominins, it had a grasping hallux or big toe adapted for locomotion in the trees.

It is not confirmed how much other features of its skeleton reflect adaptation to bipedalism on the ground as well.

Like later hominins, Ardipithecus had reduced canine teeth.

The brain of Ardipithecus ramidus, measuring between three hundred and three hundred and fifty square centimeters, is slightly smaller than a modern bonobo or female common chimpanzee brain, but much smaller than the brain of australopithecines like Lucy (around four hundred to five hundred and fifty square kilometers) and roughly twenty percent the size of the modern Homo sapiens brain.

Kenyanthropus platyop, a three point five million to three point two million year-old (Pliocene) hominin fossil discovered in Lake Turkana, Kenya, is believed to have lived in a “mosaic” environment of grassland and some forested areas.

In contrast, their close relative, A. afarensis, found in sites such as Laetoli, Tanzania, and Hadar, Ethiopia, are believed to have spent a lot of time among trees.

Maeve Leakey proposed in 2001 that the fossil represents an entirely new hominine genus, while others classify it as a separate species of Australopithecus, Australopithecus platyops, and yet others interpret it as an individual of Australopithecus afarensis.

The End of the Mousterian Pluvial and the Influence of the Laurentide Ice Sheet

The same climatic influences that had created the Mousterian Pluvial—a period of increased rainfall that transformed North Africa into a more hospitable environment—also appear to have contributed to its decline. During its peak development, between 30,000 and 18,000 years ago, a major shift in global climate patterns was driven by the expansion of the Laurentide Ice Sheet in North America.

The Laurentide Ice Sheet and Its Impact on Global Climate

• The Laurentide Ice Sheet, which covered vast portions of North America, reached an altitude of 1,750 meters (more than one mile), altering atmospheric circulation on a large scale.
• Its massive size allowed it to generate its own long-term weather patterns, which had far-reaching effects on the Northern Hemisphere’s climate.

The Jet Stream Split and the Return to Aridity

• The jet stream, the high-altitude air current that controls weather systems, was disrupted by the Laurentide Ice Sheet, causing it to split into two branches.
• This new dominant weather pattern resulted in harsher climatic conditions in multiple regions, including Central Asia and the Middle East.
• In North Africa, the climate began shifting away from the humid conditions of the Mousterian Pluvial, leading to a return of aridity.

Consequences for Human and Ecological Landscapes

• As rainfall decreased, lakes and rivers that had once supported human populations and wildlife began to dry up.
• This change forced human groups to migrate, seeking more sustainable environments, while desertification expanded across the Sahara.
• The end of the Mousterian Pluvial marks an important transition in prehistoric climate history, as it reshaped the ecosystems of North Africa and surrounding regions, influencing the movements and adaptations of early human populations.

These climatic shifts, triggered by glacial expansion in the Northern Hemisphere, demonstrate the interconnected nature of global climate systems, showing how distant geological events could dramatically alter environments thousands of kilometers away.

Advancements in Weapon Construction by 18,000 BP

By 18,000 BP, early humans had made significant technological advancements in weapon-making, improving the efficiency and accuracy of their hunting tools.

Innovations in Projectile Construction

• Flint Points Secured with Sinews

  • Flint projectile points were now firmly attached to split wooden shafts using sinews as binding material.
  • This technique increased durability and impact strength, making weapons more effective for hunting large game.

• The Use of Fletching for Greater Accuracy

  • Feathers were carefully glued and bound to projectile shafts, introducing fletching—a technique that improved stability and accuracy in flight.
  • This innovation allowed projectiles to travel farther and hit targets more precisely, making hunting more efficient and reliable.

Impact on Upper Paleolithic Hunting and Warfare

• These advancements enhanced hunting efficiency, leading to greater success in capturing fast-moving prey.
• The use of composite tools, with multiple materials such as wood, sinew, stone, and feathers, reflects increasing technological sophistication.
• The refinements in projectile design paved the way for the later development of bows and arrows, revolutionizing prehistoric hunting and combat strategies.

By 18,000 BP, humans were not only mastering stone tool production but also incorporating aerodynamic principles and multi-material engineering, demonstrating an advanced understanding of physics, materials science, and hunting strategy.

The Solutrean Tool Industry (c. 18,000–15,000 BCE)

The Solutrean tool industry, named after the site of Solutré, near Mâcon, France, was a brief but technologically spectacular phase of the Upper Paleolithic. Geographically restricted to central and western France and northeastern Spain, it emerged around 18,000 BCE in southwestern France before disappearing by 15,000 BCE.

Characteristics of Solutrean Tool Collections

• Side scrapers – The most abundant tool type, used for processing hides, wood, and bone.
• Borers and gravers – Frequently used for engraving and working organic materials such as bone and antler.
• Burins – Less common but still present, used for carving and shaping.

The Solutrean Laurel Leaf: A Masterpiece of Stoneworking

• The Solutrean laurel leaf, a lanceolate point of varying length, is the hallmark of Solutrean craftsmanship.
• The earliest examples were unifacially worked, meaning flaked on only one side.
• Later versions show bifacial retouching, making them thinner, more symmetrical, and highly refined.
• These points were likely used as projectile tips or ceremonial objects, showcasing the exquisite flint-knapping skills of Solutrean artisans.

Significance of the Solutrean Industry

• Solutrean artisans developed advanced pressure flaking techniques, allowing for thin, delicate, and finely retouched tools—a skill level unmatched in earlier tool industries.
• The geographic and chronological isolation of the Solutrean industry suggests it may have been an adaptive response to cold-climate conditions during the Last Glacial Maximum.
• The disappearance of the Solutrean tradition around 15,000 BCE coincided with the transition to the Magdalenian culture, which emphasized bone and antler tools over highly flaked stone points.

Despite its brief duration, the Solutrean tool industry represents a peak of Paleolithic stone craftsmanship, demonstrating a level of precision and artistry that remains one of the greatest achievements of Ice Age technology.

The four northern Channel Islands off California, including Santa Rosa Island, were conjoined during the last ice age into Santa Rosae, a single island that was only five miles (eight kilometers) off the coast.

Geography took its present shape after the continental ice sheets melted and sea levels rose one hundred and twenty meters.

There is also evidence to suggest that a submerged island, Calafia, lay between Santa Rosae and the mainland.

A thirteen thousand-year-old skeleton—the Arlington Springs Man—found on Santa Rosa island demonstrates that the earliest Paleo-Indians had watercraft capable of crossing the Santa Barbara Channel, and lends credence as well to a "coastal migration" theory for the peopling of the Americas.

This is the oldest set of human remains yet found in North America.

Pygmy mammoths (Mammuthus exilis), which became extinct more than ten thousand years ago, have also been excavated here.

The approximate geography of Denmark as we know it today has been shaped by around 6000 BCE.

Denmark has some unique natural conditions for preservation of artifacts, providing a rich and diverse archeological record from which to understand the prehistoric cultures of this area.

The first inhabitants of this early post-glacial landscape in the so-called Boreal period were very small and scattered populations living from hunting of reindeer and other land mammals and gathering whatever fruits the climate was able to offer.

Around 8,300 BCE the temperature had risen drastically, now with summer temperatures around 15 degrees Celsius, and the landscape changed into dense forests of aspen, birch and pine and the reindeer moved north, while aurochs and elk arrived from the south.

The Koelbjerg Man is the oldest known bog body in the world and also the oldest set of human bones found in Denmark, dated to the time of the Maglemosian culture around 8,000 BCE.

With a continuing rise in temperature the oak, elm and hazel arrived in Denmark around 7000 BCE.

Now boar, red deer, and roe deer also begin to abound.

A burial from Bøgebakken at Vedbæk dates to about 6,000 BCE and contains twenty-two persons—including four newborns and one toddler.

Eight of the twenty-two had died before reaching twenty years of age—testifying to the hardness of hunter-gatherer life in the cold north.

Based on estimates of the amount of game animals, scholars estimate the population of Denmark to have been between thirty-three hundred to eight thousand persons in the time around seven thousand BCE.

It is believed that the early hunter-gatherers lived nomadically, exploiting different environments at different times of the year, gradually shifting to the use of semi permanent base camps.

India's Sarasvati River, mentioned in all books of the Rigveda except the fourth, and celebrated as the central watercourse of Vedic culture, may end its oceangoing flow as early as 8000 BCE.

The Nadistuti hymn in the Rigveda (10.75) mentions the Sarasvati between the Yamuna in the east and the Sutlej in the west, and later Vedic texts like Tandya and Jaiminiya Brahmanas as well as the post-Vedic Mahabharata mention that the Sarasvati dried up in a desert.

The goddess Sarasvati was originally a personification of this river, but later developed an independent identity and meaning.

The Ghaggar is an intermittent river in India, flowing during the monsoon rains; the Hakra is the dried-out channel of a river in Pakistan that is the continuation of the Ghaggar River in India.

Evidence from survey fieldwork and recent satellite imagery have been adduced to suggest that the Ghaggar-Hakra system in the undetermined past had the Sutlej and the Yamuna as tributaries, with the Rann of Kutch as the likely remains of its delta.

In this scenario, geological changes diverted the Sutlej towards the Indus and the Yamuna towards the Ganges, following which the river did not have enough water to reach the sea any more and dried up in the Thar desert.

It has been proposed that the Sarasvati of the early Rigveda corresponds to the Ghaggar-Hakra before these changes took place (the "Old Ghaggar"), and the late Vedic end Epic Sarasvati disappearing in the desert to the Ghaggar-Hakra following the diversion of Sutlej and Yamuna.

The wide paleo-channel of the Ghaggar river suggest that the river once flowed full of water during the great meltdown of the Himalayan Ice Age glaciers, some ten thousand years ago, and that it then continued through the entire region, in the presently dry channel of the Hakra River, possibly emptying into the Rann of Kutch.

It supposedly dried up due to the capture of its tributaries by the Indus system and the Yamuna river, and later on, additionally, the loss of water in much of its catchment area due to deforestation and overgrazing.

Members of the Homo genus have intermittently inhabited Britain for hundreds of thousands of years; Homo sapiens have done so for tens of thousands.

DNA analysis has shown that modern humans arrived in Britain before the last ice age but retreated to Southern Europe when much of Britain was ice covered, with the remainder being tundra.

At this time, the sea level was about one hundred and twenty-seven meters (four hundred and seventeen feet) lower than it is today, joining Britain to Ireland and the area known as Doggerland to the continent of Europe.

Britain had been reoccupied by 12,000 BCE as shown by archaeology.

The climate from twelve thousand seven hundred to eleven thousand five hundred years ago, in what is known as the Younger Dryas period, became cooler and dryer.

Food animal populations seem to have declined although woodland coverage has expanded.

Tool manufacture in the Final Upper Paleolithic revolved around smaller flints but bone and antler work became less common.

Typically, there are parallel-sided flint blades known as "Cheddar Points.” However, the number of known sites is much larger than before and more widely spread.

Many more open-air sites are known such as that at Hengistbury Head.

The ice age finally ends around 8000 BCE and the Holocene era begins.

Temperatures rise, probably to levels similar to those today, and forests further expand.

The Mediterranean Sea swells and seawater surges northward, slicing through the natural dam at the Bosporus in what is now Turkey sometime around seven thousand five hundred years ago, according to a theory proposed in the late 1990s by Columbia University geologists William Ryan and Walter Pitman.

According to this theory, around 5500 BCE, a wall of seawater, funneled through the narrow Bosporus, hit the low-lying freshwater lake with two hundred times the force of Niagara Falls.

Fueled by the infinite waters of the Atlantic, Pacific and Indian Oceans, the seawaters rushed in for the next year or so, maybe longer.

Under this scenario, each day the lake level would have risen about six inches, flooding coastal farms, inundating whatever communities might have existed and forming what will be called the Black Sea, ultimately increasing the lake's area by a third.

Surviving marine life was driven into the newly abbreviated estuaries of the Danube, Dniester, Dnieper, Don, and Bug Rivers.

In flatter coastal areas, the shoreline may have advanced as much as a mile a day.

This hypothesis has been the subject of considerable discussion, and a news article from National Geographic News in February 2009 reported that the flooding might have been "quite mild.” While it is agreed by all that the sequence of events described did occur, there is debate over their suddenness and magnitude.

In particular, if the water level of the Black Sea were initially higher, the effect of the spillover would have been much less dramatic.

According to a study by Giosan et al., the level in the Black Sea before the marine reconnection was thirty meters below present sea level, rather than the eighty meters or lower of the catastrophe theories.

If the flood occurred at all, the sea level increase and the flooded area during the reconnection were significantly smaller than previously proposed.

It also occurred earlier than initially surmised, around 7400 BCE rather than the originally proposed 5600 BCE.

Food crops such as wheat and maize become standardized in this age.

The domestication of maize is of particular interest to researchers—archaeologists, geneticists, ethnobotanists, geographers, etc.

The process is thought by some to have started twelve thousand to seven thousand five hundred years ago.

Research from the 1950s to 1970s originally focused on the hypothesis that maize domestication occurred in the highlands between Oaxaca and Jalisco, because the oldest archaeological remains of maize known at the time were found there.

Genetic studies led by John Doebley identified Zea mays ssp. parviglumis, native to the Balsas River valley and known as Balsas teosinte, as being the crop wild relative teosinte genetically most similar to modern maize.

However, archaeobotanical studies published in 2009 now point to the lowlands of the Balsas River valley, where stone milling tools with maize residue have been found in an eighty-seven hundred-year-old layer of deposits.