A Method of Dying

"Death comes to all, but great achievements build a monument which shall endure until the sun grows cold." _Emerson

The brain is an expensive organ. It consumes 20-25% of the adult, and 70-75% of the infant (newborn), energy stores; 2/3rds of this organ is composed of fats. Your brain uses these fats from your diet to build it's cell membranes. Myelin, the protective tissue that sheaths neurons, is 30% protein and 70% fat. Myelin is essential to our nervous system, as it accelerates nerve impulses and neuron communication. This efficiency allows for the brain and nervous system to streamline.

Mammals have a distinction, in that, we do not lay eggs and expel a tremendous amount of energy in supplying the external embryo with nutrients. Instead, the placenta provides such calories and reserves internally, with 70% of its energy destined for brain growth. While pregnant, the fatty acids derived from diet are supplied to the fetus, and continue to fuel its external development through breast milk. Yet the brain grows most rapidly in the womb. Any deficiency in the required amount of fat intake diminishes the placenta, which leads to low birth weight, and most importantly, a smaller brain size at birth - endangering or dooming development and cognition. Thus, fat is the key building block to brain growth and cognitive ability. 

The human female is the foundation and driver of the vast majority of our evolution. Aside from birthing our entire species, pregnancy and lactation - her dietary needs are what propelled our subsistence and social strategies. 

"During the time a mother is breastfeeding, complex hormonal adjustments in her system forestall menses in all but a few cases. Within a month or two after separating her toddler from her breast, just as night follows day, the mother begins to menstruate again. But a new factor will cause her to loose more blood than she did prior to her pregnancy. Once a woman has had her first child, the increased size and more robust vascularity of her uterus will cause a small but significant increase in menstrual loss of iron. Each subsequent pregnancy will be followed by a slightly heavier menstrual flow, and this trend will continue for the rest of the woman's reproductive life.

By one avenue or another, a woman is always losing iron. Over a lifetime, the average woman loses the equivalent of approximately fifteen gallons of iron-rich blood due to menses, pregnancy, delivery, birth trauma, etc...." 

_Leonard Shlain, Sex, Time and Power

Hemoglobin is an iron-rich protein which makes our blood red. The iron in hemoglobin seeks out and "grabs" oxygen, releasing it where needed, making it the most efficient carrier of oxygen to every organ in the human body. Hemoglobin plays the key role in neuron function. Blood loss of any kind results in a loss of hemoglobin, thus iron to carry oxygen through the circulatory system. The result is inertia, anemia and a weakened immune defense. "This sets up a vicious cycle to break. The more anemic a woman is, the more blood she loses, making her more anemic and causing increasing iron loss."(L. Shlain, 2003)

On average, a human female loses up to 40 quarts of blood during her lifetime of menses. Every four weeks, a woman sheds her uterine lining with several (4-8) milliliters of blood loss; Nature's way of ensuring an optimized environment for fetal development. In utero, the only source for iron for the fetus is the mother's stores. The mother must keep up the oxygen supply to her developing fetus in the womb, without neglecting her very own oxygen requirements. In the last months of development, the fetal brain consumes 3/4th's of the energy delivered by the umbilical. Laying out all of the blood vessels of the human female's placenta would stretch thirty miles (L. Shlain, 2003). The Daily Energy Expenditure (DEE) for a woman of reproductive age is, thus, slightly higher than the adult male - despite larger male body size. 

Anthropologists have noticed that menses, and the amount of associated blood loss, has increased throughout the history of our species. In my view, this has strong correlation with brain development. 

There are 400 miles of capillaries within the human brain. The health of that vascular system and the blood it contains is vital to brain performance, vital to higher intelligence. 

Some 3,700 years ago, Hammurabi, ancient law-giver and the king of Babylon, had delivered his famous code - "an eye for an eye." Civilization was quite underway. And half a world away, on Wrangel Island, off the cost of Siberia, the last woolly mammoth fell into extinction. 

In the last post, we discussed the clades and refugia of our human ancestors. Consider as well, that these refugia were home to other fauna/flora than ourselves. That, in our migration, tracking and hunting of large game, equally at the mercy of climate change, is what led us Out-of-Africa and into these New World refugia. At the outset, some 1.9mya, at the time of Homo erectus' first migration, there were 12 species of proboscids (elephants) that roamed the planet. Today, there exists only 3 (African savanna, African forest, and Asian). And those 3 genetically diverged at the beginning of the time when Homo erectus left Africa. 

During these Pleistocene times, between glacials and interglacials, stadials (lower temperatures during interglacials) and interstadials (slightly warmer during glacials), the average temperature could change by as much as 41°-50°F, within a few decades time. During glacial maxima (heavy ice ages), the temperature could be up to 69.8°F colder in comparison to today. "Only during these times did the northern hemisphere conform to the movie image of the Pleistocene with extensive glaciers covering large parts of Eurasia and North America...sea levels being 393ft lower, exposing more land mass. The British Isles were connected to Europe and the North Sea being a large area of dry land. ...It was during these times that elephants (extinct species) and hippopotamus were living as far north as the British Isles." (Hofreiter & Stewart, 2009) At 700kya in East Anglia, England, Homo heidelbergensis had tracked these proboscids and pachyderms to the western edge of Europe.

The increase in brain size undoubtedly forced a necessary shift in diet - making larger, fatter game attractive and necessary. For Australopiths like Lucy, from whom our genus Homo evolved, the intake of plant foods was not enough to feed a growing brain. The very acquisition of plant foods was so time consuming, it left little space for anything else. In observance of baboons, "devoting almost all of their daylight hours to painstakingly seeking out small, nutritious food items...adult male baboons may pick up as many as 3,000 individual food items in a single day." (Milton, 1987) They lacked the capacity to adapt both in subsistence and against the pressures of climate change. So, with Homo erectus, none of the physical traits that accompany a high amount of plant food consumption are found in their skeletal remains. Their teeth and jaws are smaller than their predecessors, indicating a shift to a diet that includes, not only meat, but cooking. The loss of jaw muscle in the mandible, also relates to the cranium where those large jaw muscles are attached. When those muscles decrease in size, it releases cranial pressure, allowing for a larger brain. We can say cooking as so did their intestinal tracts shrink. Cooking implies less metabolic demand on the intestines to digest high fiber plant matter - which takes longer to extract nutrients, hence a large digestive tract. Reduced occlusion (crowdedness in the teeth) indicates a shearing of food, which implies a reduction in hardness. This lessened metabolic demand also provided more energy reserves to a growing brain. The thinner rib cage, housing a much smaller large intestine, would allow for longer limb growth and agility. In weight, the human gut is 60% of that which would be expected in a primate of similar size - even more obvious when we simply look at the robust torso of gorillas. 

The McHenry quotient is ratio expressing the post-canine dentition area in relation to body mass:

• Homo habilis (1.9)
• Homo erectus (1.0)
• Neanderthal (0.7)
• Homo sapiens (0.9)

These differences can first be seen dramatically between Homo habilis (the first tool-maker) and Homo erectus (the first Out-of Africa, and to carry their tools with them). Nearly half of a reduction in masticating teeth size compared to gut is hard evidence for the use of fire and cooking.

"The need to consume animal fat is the result of the physiological ceiling on the consumption of protein and plant foods. The obligatory nature of animal fat consumption turned the large prey preference of Homo erectus into a large prey dependence." (Ben-Dor, Gopher, et al, 2011)

At the same time, let's dispel a myth. It was believed that Neanderthal's had an all meat diet. If so, the species would have died out due to "protein poisoning." So, as evolution, introgression and migration goes - they would have, first, inherited the subsistence patterns of their immediate predecessors (Homo heidelbergensis who inherited theirs from Erectus). Second, they would have either adopted from other groups new patterns of subsistence, or, lastly, created their own for survival when migrating to new refugia with a differing ecosystem, a habitat of different flora/fauna. For, too much meat is too much protein. The conversion of protein to energy requires liver enzymes to dispose of nitrogen, an ingredient of amino acids which compose the protein molecule. Consumption of proteins by humans is thus limited by the capacity of the liver to produce such enzymes, and of the kidney to dispose of urea - the nitrogen containing by-product from metabolism of proteins by the liver. 

"By comparing modern human, Neanderthal and Denisovan genomes, the researchers identified more than 31,000 genetic changes that distinguish modern humans from Neanderthals and Denisovans. These changes may be linked with the survival and success of modern humans - a number have to do with brain development. If one speculates that we modern humans carry some genetic changes that enabled us to develop technology to the degree that we did and settle in nearly all habitable areas on the planet, then these must be among those changes." _Kay Prufer, Max Planck Institute, 2013

If iron molecules are in the presence of other animal proteins, the cells lining the stomach wall allow for more rapid diffusion of iron into the blood stream, thus more oxygen and more energy to metabolize. "Meat protein digestion is costlier compared to fat and that a larger percentage of protein escapes digestion, while fat digestion is nearly complete." (Ben-Dor, Gopher, et al, 2011) So, rather naturally, our hominin ancestors could certainly detect that consumption of fatty meat metabolizes energy more rapidly. 

Upon the second wave of human migration out-of-Africa (<1.6mya), along the back of Acheulean hand axes, comes the hunting of larger game. At Acheulean sites throughout Asia, Africa and Europe - there are elephants. Acheulean hand axes found at Homo erectus sites are much larger, in strong correlation with the large amount of elephant and hippo bones. 

Given the physiological energy needs of female members of the group, a forced and at times rapid evolution during the vicissitudes and vacillations of the glacial Pleistocene, and an abundance of large bodied ice-age animals - the adoption of elephants as their primary prey seems more like an inevitability than a choice, once examined. 

Yet, elephants, mastodons, and mammoths do not run away, relying on their size to intimidate any such bold prey. They are easy to find - being conspicuous, not camouflaged and typically using the same migratory paths and water holes, making them easy to trap and/or ambush. 

Still, the capturing of such a large beast would perhaps force the cooperation and aggregation of several small groups. This social cooperation very soon, leads to the establishment of hunting camps. And it's at these hunting camps that we can detect a shift in the hunting and subsistence strategies of our ancestors. Incentivized social cooperation and sharing is what led to the initial fraying of in-group/out-group rigidity. "We can all eat from this; bring your hunters...," or "Your tools can help us...," or "We tracked them here, you know this land best, lets work something out," laid the foundations of a more rapid socialization and technological development. But, we must consider this to be true only in areas with varying human populations. DNA evidence suggests a significant amount of in-breeding in these refugia.

At Gesher Benot Yaaqov, an Erectus camp-site in Isreal, ~780kya, these camps became specialized - with a particular setting dedicated to the extraction of...elephant brains from skulls, another for the extraction of marrow from the bone. There were places set aside for different kinds of butchering, defleshing, cutting and plant food processing. Some three-quarters of a million years ago, we see the embryonic foundation of sedentarism (residing in one place, not migratory). Though these sites were seasonal, and they remained migratory, derived from the need to track and stay in vital proximity to their food sources. But since Gesher Benot Yaaqov was occupied for more than 50k years by Erectus, surely a return to familiarity begins to establish ideas of home. And since the area surrounding The Pit of Bones in Spain was occupied for nearly 400k years - by Heidelbergensis, perhaps Denisovan and then Neanderthal - we can see this habit taking shape far earlier than is commonly believed with the onset of agriculture, I would argue, between 30k-11kya. Familiarity with previously utilized hunting grounds (migratory paths also reused by prey animals), and returning to established hunting camps led to the adoption of a home-based hunting strategy; it further freed up energy for brain development, hence, the specialized camps. 

The preference for such a large animal, like mastodons, mammoths, and elephants, is it's fat constituency. Despite climate change, all hunting is thus seasonal. A long dry season, as seen in Africa, the Near East, parts of Asia during the Pleistocene, and even today, means prey animals would be much leaner. During a dry season, vegetation is also minimal, further exacerbating a prey animals' need for fat, and this trickles down through the carbon cycle (food chain). Meaning you'd have to hunt more of them to gain the normal amount of required nutrition to stay alive. 

Seasonality is a cycle that can stress - and we, today, in the northern hemisphere especially, pack on ~14 extra pounds during the holiday season (historically harvests would have come in-between the vernal equinox and the winter solstice - now celebrated as holidays with feasts, subconsciously packing on winter pounds to endure the season). This would induce subsistence stress if earlier humans simply picked off animals of all shapes, ages and sizes of a prey species. These populations would have difficulty maintaining reproductive age animals and reproducing themselves. However, we begin to notice a deduced preference for prime-age animals with Homo erectus. Native Americans were observed to have had a particular knack for picking out the animal, that to you and I would seem normal, but from experience, they knew to have superior fat content - simply by the way the skin and fur moved across the muscle, the sheen of the coat and its curves. As such, an early hominid hunter, dependent on his prey and an expert at tracking migratory animals, would certainly have employed this same trait. Seeking out prime-age animals helped supplement the negative, at times dire, effects of seasonality.

Erectus, Heidelbergensis, Denisovan, Neanderthal, etc. were literally focusing on their own survival, not dominance. We introduce a contextual danger when we view them through the lens of modern humanity's global dominance - in spite of their intelligences. They were not apex predators. The dependence on large prey animals like proboscids and pachyderms (which includes hippopotami, and rhinos), also brought about its inherent dangers. Being evolved from scavengers fed into its hunting strategy, which when employed, attracted other large-bodied scavengers to follow even them. For example, grazing animals migrate, prey animals follow them (hominins and other carnivores), and scavengers track them all. As there were clades of humans in refugia, there were clades of giant and cave hyenas, etc. "Their migrations conspicuously match up with major events in hominin history." (Hofreiter, Stewart, 2009). 

At Dragon Bone Hill, in Zhoukoudian, China, from ~700ky, the site was occupied intermittently
by a den of giant hyenas first, then later by Homo erectus, hyenas again, then Homo sapiens. The Erectus bones are mainly skulls that show signs of being eaten by giant hyenas. There are zero post-cranial remains (arms, legs, ribs, etc.). The hyenas were crushing at these bones to get at the fat-rich marrow and either passing them through digestion or scattering them in the process. The craniums were bitten into to get at the fat-rich brain matter. Then Erectus took over the site again. So, not only is fat preferred by carnivores (they tend to go for the guts first, and also eat the brains and marrow), but Erectus was a competing member of a carnivore community - filled with giants like hyenas, cave bears and lions. If we did not inherit our courage from them, then someone kindly identify where.

But, the real danger was dependence itself, a dependence on prime-age animals. Again, as climate change forces both evolution and adjustment in us, it pressures other animals. The Levant, where these hunting camps first appear, is a major conduit out of-, and into-, Africa. It also experiences a prolonged dry-season. So, the hunting of prime-age animals could have pressured large prey animals like other species of elephants into extinction; the thinking being the ability to reproduce a population and sustain reproductive age animals. The elephant was particularly sensitive - if a mere 4% of reproducing adults are hunted, the population as a whole is in real danger of dying out. (Pigs, by contrast, can suffer a 50% hit) Couple that with their fearlessness based on their size, and their predictability in terms of migration and water holes. Additionally, they move in large herds, and as a result, are hunted in such. And - our very real dependence on the dietary fat they provided a group of humans. They were not hunted to extinction by hunting the entire population. The prime-age adults suffered too much predation by early humans, against climate change. 

And then, abruptly, the disappearance of elephants from the archaeological record is clearly evidenced during the transition from the Acheulean tool industry, ~500kya, into new and evolving industries like the Acheulean-Yabrudian industry in the Levant. This industry evolved from the need to hunt faster, smaller game. And more of it to supplement what was missing from larger prey. 

Recall, this is around the same time, at the Pit of Bones, that Heidelbergensis began to evolve into Neanderthals - due to climate change. And elsewhere in Africa, Heidelbergensis begins to diverge into Homo sapiens. Yet, these Neanderthals had a greater caloric cost than modern humans. Our critical temperature (internal heat production maintained without clothing) is 28.2°C, while their more stocky bodies were maintained at 27°C - hardly adapted to the cold. Thus, they had to hunt more meat - just at the time when elephants en masse begins to fall out of the hominid diet. Neanderthals moved from pachyderms, to smaller game like giant deer, bison and wild horse - over time. What aided their dietary requirements against their subsistence strategy is their group size, typically no more than 14 individuals. They not only ate plants, but cooked them. "Plant microfibers and remains can be recovered from dental calculus (mineralized dental plaque that forms on teeth) and on stone tool remains," says Alison Brooks of the Smithsonian and George Washington University. They ate 50 different types of leaves, roots, water lilies, stems and starch grains like barley - and typically boiled them in water, as indicated by micro-remains. 

By deduction, we can assume that since modern human hunter-gatherers residing in deserts, like the Kalahari Bushmen, eat over 82 varieties of plants in these desolate areas...and that Neanderthals ate over 50 varieties, that Heidelbergensis and previously Erectus did as well.
So, from the skeleton, we can piece together a behavioral study. And from DNA, we can logically deduct a social history. We can literally begin to distinctively classify our ancestors by not just their morphology or DNA, but by their energy requirements, what they hunted and ate:

Body Size:

• Group A (Elephants > 2200lbs)
• Group B (Hippos, Rhinos, etc. <or= 2000lbs)
• Group C (Giant deer, red deer, bear and bovines, etc. 175 - 500lbs)

Energy Gained from Food Items:

• Seeds and Nuts (3,520 - 6,508 kj/hr)
• Roots and Tubers (1,882 - 6,120 kj/hr)
• Large Game (60,000 - 63,398 kj/hr)

Unfortunately, we do not have DNA samples from Homo erectus to show us how closely related they were to Heidelbergensis, Denisovans, Sapiens or Neanderthals. But, the 2% of our modern genome, and the upwards of 6% of Denisovan genome that remains unassignable to any known human genome, may yet be Erectus finally speaking through history with the aid of technology. Having survived for nearly 2 million years - from scavenger, to hunter, to hunting big game, to eventually adopting small game hunting techniques from either Neanderthals or modern Humans before their ultimate demise - we not only see a resultant morphological shift, but a truly learning and adaptive human being.

With a hungry brain, fat intake become obligatory.Today, there is 66% fat in the Masai (Kenya) diet, between 48-70% of fat intake in the Inuit (Eskimo) diet. The average American consumes 45% of fat in their diet, which is further supplemented by fats from fish, legumes, and oils. Despite the warnings, there are no negative health effects. The only negative is calorie intake vs calorie expenditure - we are too sedentary compared to our more mobile ancestors from which we inherited these requirements - and the amount of synthetic chemicals ingredients in our food items (50 new chemicals in the human body since 1900). There is a lifestyle mismatch, and our bodies cannot evolve fast enough to keep up with our technologies. Yet, still, this shapes our evolution all the while. 

As far as refugia, DNA evidence suggests that though we can detect species as being morphologically different, and geographically separated - its genetic diversity may indicate something else entirely. The genetic history of the Heidelbergensis/Neanderthals which occupied Atapuerca, Spain yielded DNA which also denotes a Denisovan ancestry. Up until now, we believed Denisovans went no further west that Siberia. It becomes obvious that admixture took place more often than simple "refugia" would allow. As previously mentioned, I believe these exchanges took place during interglacials and interstadials. As we are ultimately animals, further examples supporting this admixture evidence comes from clades of cave bears. One ancient clade resided in Siberia and the Caucasus Mountains, and the other resided in the Atlai Mountains near Mongolia, China, Russia and Kazakhstan and Western Europe. Despite geographic distance - they were genetically relative. Simply put, those bears in refugia in between, died out. 

"These population extinctions can be seen as a continuum with the extinction of a species simply being the ultimate result of a succession of population extinctions." (Hofreiter & Stewart, 2013)

From refugia to refugia, clades of elephants died out. Clade upon clade of Pleistocene prey and predators followed them into the refuge of time - from the cave bear to the hyena. The dependent humans were faced with a dire challenge. And, in refugia after refugia, some populations went extinct. This is how we see Denisovan DNA in Western Europe and Neanderthal DNA in North Africa, where there is no evidence of their physical existence. 

Neanderthalensis

We shift according to dietary needs propelled by the energy requirements of an evolving brain, and evolve based on what the climate/biological interface allows. The human female, not only shaped our intelligence, shaped our social dynamics, but informed male hunting strategy. 

Extinction is an inevitability. We, as Homo techne, need only to decide if this Earth is the final refugia.

On Higher Ground and the Clines of Humankind

“Every man has forgotten who he is. One may understand the cosmos, but never the ego; the self is more distant than any star. Thou shalt love the Lord thy God; but thou shalt not know thyself. We are all under the same mental calamity; we have all forgotten our names. We have all forgotten what we really are. All that we call common sense and rationality and practicality and positivism only means that, for certain dead levels of our life, we forget that we have forgotten. All that we call spirit and art and ecstasy only means that for one awful moment we remember that we forget.”
 _G.K. Chesterton

cla·dis·tics

kləˈdistiks/

noun

BIOLOGY

1. a method of classification of animals and plants according to the proportion of measurable characteristics that they have in common. It is assumed that the higher the proportion of characteristics that two organisms share, the more recently they diverged from a common ancestor.

re·fu·gi·um

riˈfyo͞ojēəm/

noun

BIOLOGY

plural noun: refugia

1. an area in which a population of organisms can survive through a period of unfavorable conditions, esp. glaciation.

Peering deeper into human evolution by pouring over scientific papers and publications of the most recent findings and interpretations - you'll find a lack of consensus, varying schools of thought, and flat out arguments on shared subjects. Each scientist has their background and, thus, bias. Still, each perspective is valuable to the whole, and just as light through a prism has its rainbow of constituents that together make light itself - so do these varying points of view make a unity of our past.

Attempting to pinpoint the first learned use of fire by our genus Homo gives us a wide range of dates from 200kya to 1.7mya. The most recent evidence presented by scientific papers trends toward pushing the dates of fire use back into the age of the Oldowan tool-making industry >1.6mya. The earliest sites indicating habitual fire use are Wonderwerk Cave in South Africa at 1.7mya, then Koobi Fora in Kenya at 1.5mya, and Chesowanja in Kenya at 1.4mya. We will continue to see, especially with the emergence of modern human behavior, how this corridor from South Africa to East Africa to the Levant and into Eurasia was a repeating conduit for the spread of behavioral and technological developments. 

Just as in politics and from any age, you have conservative and liberal viewpoints among scientists. And the middle ground or general consensus being that fire use became widespread somewhere between Neanderthals and Homo Sapiens, no greater than 400kya. Yet, here, let me differentiate for proper understanding on how technologies may live or die. Understand, genetic and behavioral changes within a small population may spread rapidly. It's simply a smaller gene pool and thus genetically vulnerable to disturbance. But technological dissemination must roll out on the back of varying populations, each susceptible and under the guise of heritable culture. So, now Science is beginning to distinguish: Early Fire - specific and isolated paleolithic sites, from Late Fire - wide ranged habitual use <400kya. This is not hard to understand as today some have access to the Internet and some do not. Or better yet, some have access to capital and can understand it's best application, and some lack both access and understanding. But all innately understand the transference of information, in terms of the internet; virtually all understand using some valued or shared belief in an object as money for a medium of exchange. But what is missing as a fundamental element of understanding within the consensus on the use of fire is how it is ever so natural to develop. 

I came across a study by Lillian M. Spencer from the University of Colorado, on the savanna adapted antelope living at the time when Homo erectus first evolved, and a species of antelope which it ate. Based on the soil samples at sites where these fossils were found, these antelope were adapted to grasslands called secondary grasslands. Secondary grasslands are naturally, and most importantly, humanly, maintained. Not just these antelope, but grazing species of large herbivores in general became adapted to secondary grasslands just as Homo erectus evolved from Homo habilis, 2 million years ago. Now, secondary grasslands are maintained by fire that is caused by the increasing aridity of the climate. And if a species is forced by climate to evolve from a scavenger into a hunter, as stated in a previous post, it's not a wide gap between conceptualizing how a scavenger would naturally turn into a hunter in hard times. A scavenger observes first; they have to for their own safety. That observation is knowledge of where and when prey animals move and the predators that track them. It must be repeated that this is knowledge. Nothing random about it.

Professor John Gowlett of the University of Liverpool, "Bush fires in Africa, and probably elsewhere, are used by intelligent predators as a means of trapping prey. Animals such as cheetahs will position themselves so as to pounce on animals fleeing from the flames, and hawks will do the same." It's not a stretch for Homo habilis, as a scavenger, to have watched the movements of cheetahs, or even to watch the sky for buzzards and recognizing and following raptors as possible. Birds are commonly observed flying over wildfires capturing escaping insects. This is a natural behavior among many predators.

If non-human animals are intelligent enough to use fire in this manner, it is more than likely our early ancestors did also. But, one of these intelligent ancestors got closer, and picked up a burning stick. Whether it was used in a dominance display over a food or status conflict, or to further prod a dangerous and dying animal escaping from the flames and soon to be its prey, is unclear and will never be known. But what is known is that someone was watching, and someone mimicked, and then someone else until this particular group became dominant and successful. And if they could preserve and maintain this fire (transferring it to camp sites and lighting different consumables for later use), then they could set one - not create fire itself (I believe that would come later), but control it when found and maintained for hunting and cooking purposes. This could be the original purpose of hearth-building. 

It is my conclusion that this development, along with climactic changes pushing the Sahara Pump, along with early proto-language, and along with changing gender dynamics, aided the spread of the genus Homo out of Africa. And knowing that phantom evidence of a camp fire almost 2 million years old is nearly impossible with rapid erosion of ashes and cooked remains outside of bones, the archaeological record would, at first, be scant. But we see this as changing with evolving soil sampling techniques. And yet, the morphological record backs up this theory, as the genus Homo became more gracile (thinner torsos, longer limbs), the dentition became less occlusive (less crowded, smaller canines), and as a result, the brain case was less constrained by robust jaw muscles required to chew tough uncooked food items.

And that fire would have altered gender dynamics. As hunting became more wide-spread, and fire use became the norm - there is a delayed gratification and accumulation associated with cooking. You don't eat on sight of the kill. You butcher, you haul, and you wait. And the gatherers would be expert in advising on delayed gratification. So, if fire use and cooking were becoming more prevalent, we would begin to see it in the dimorphism (the difference in size between genders) in between Homo habilis and Homo erectus. And that we do - we see not only a decreased dimorphism, but an increased socialization. "Language, similar to what Homo sapiens employ, has it origins somewhere between 1.8mya and Homo heidelbergensis (~900kya) - due to new paleoanthropological, archaeological, and genetic reassessment of older data in lieu of and availability of ancient DNA." (Frontier in Language, Science 2013). Males would have to be more resourceful, than dominant; further sparking human intelligence - due, again, to female selection. 

This would not be the case for an entire species until "Late Fire," just as we have virtual hunter-gatherer populations today, in the midst of wide-spread technological dissemination. And it would not be the case for other sister-species in the genus Homo, as some would dimorphically "revert" (Neanderthal, perhaps Denisovan), and some would "advance" (Heidelbergensis, Sapiens). 

So we should view behavioral and technological adoption across a spectrum of species, time and place, instead of grouping it with widespread, automatic selection.

Within Africa, high-quality raw materials were available that "allowed for the full expression of technological skills," according to Yonatan Sahle of University of Capetown and University of California at Berkeley. These material sites were not far from mega-lake sites that "supported a bigger population. These mega-lakes might have attracted stable occupation, further fueling technological advances." 

But this is a regional bias. Because within a million years of wide-spread stone tool industry - peoples, and their technology with them, had traversed the Old World. So, Africa is the beginning, and will also be the beginnings of Homo heidelbergensis, archaic and modern Homo sapiens. Yet, not so for Homo antecessor, Homo neanderthalensis, Homo denisovan, or Homo floresiensis. Within and within these distant populations - we would recognize race, ethnicity and culture as we see it today.

With that recognition comes the understanding of self-identification and in-group and out-group categorization. Just as chimpanzee troops fight and maintain their territories against the out-group, early humans, the world over did the same. Violently.

First, with Homo erectus, as populations spread across Eurasia, there would be founding populations in domains and other populations spreading out nomadically, continuing to follow migrating prey animals. In particular, elephants (a literally vital relationship). They were gradually becoming the apex predator in new territorial enclaves of what is today Great Britain, Germany, France, Georgia, the Balkans, Turkey, Greese, Israel, Siberia, China, India, from tropical to temperate zones, until they would reach Indonesia. But no more of a population size of 2 million erectus - globally. Within this population, we could consider it wide and dispersed, with little or no contact between territories. And these regional enclaves would be at the mercy of climactic events over geological time, refugia - over a million years. These climactic and ecological effects would have distinctively shaped these isolated populations, into races. "The tinyness of the number of our human ancestors allowed a rather rapid evolution away from other groups who were also evolving in other small groups," says Robert Wyman, Professor of Microbiology, at Yale University. We would see an Asian Homo erectus, a European one, an Australasian race, and the founders, with some still migrating Africans (dubbed Homo ergaster within Africa).

For us Homo sapiens, it would only take 40k-70k years for our races to develop into what we are today. And only ~10K years for skin color to be reflected genetically. Less than .002% of our DNA reflects these superficial changes, according to the Human Genome Project. But, as blood types, cultures and language groups ignore borders - we are all morphologically and genetically the same species. For Homo erectus, we're talking about a period of 700k years (1.9mya - 1.2mya) until these populations in refugia develop from races into morphologically different species of Homo. 

Homo erectus - Levantine

Homo erectus - Ergaster - Africa

Homo heidelbergensis - Founder of Homo sapiens, Neanderthal and Denisovans, Africa and Eurasia until 200kya

Homo floresiensis, "The Hobbit" - Indonesia until 18kya (dwarf erectus)

Without art, without tribal jewelry, without body paint, without ocher or symbolic representation of some sort - despite their intelligences, it would have been hard to identify a stranger as friend or foe. They may simply not have cared to, due to experience and memorable history. More than likely, as competing groups of hunters - indeed they were foes. And with nomadic, dark-

skinned Homo erectus continuing to spread out of Africa, the difference in skin tone of a lighter complexion Eurasian erectus stranger would complicate interpersonal communication (possibly no shared language) - thus feeding into the idea of identifying the out-group as a foe. Just as today, protection of resources against the unidentifiable intentions of a strange out-group is what informs racism. Though it is actually an extension of this in-group/out-group dynamic.

The question arises, with widely dispersed groups, how these populations maintained themselves genetically? As usually, in male-bonded and dominated groups - the females seek (at their peril) mating bonds with males of a neighboring out-group. It decreases the prospect of harmful in-breeding, weakening the integrity of the genome, much less, the immune systems of its phenotype. So, the impetus is not conscious, but still natural. And that natural impetus feeds into the socio-sexual dynamics of the group. Chimpanzees kills females with children from an out-group, and will likely welcome a young, fertile, childless one into their own. So, as more fossils become available within these regions, alluding to what social dynamics can be gleamed - this would be a necessary topic to explore. But in what bones we have, we have an indication of some proximity of communities and the social exchanges within these archaic hominids.

As a reference (though not as a solid indication), for pre-civilization humans (courtesy of Professor Robert Wyman, Yale University):

• 56% of infants (0-3) died violent deaths
• 74% of ages 4-14 from violent deaths
• 46% of adult age died from violent deaths

In each of these age ranges, violence is the dominant form of death. More individuals die in the first three years of infancy - 15% more likely. This is not including death from accidents on the hunt or attacks by animals. Nor does it include communicable disease.

Instead, like chimpanzees, this is evidence of guerrilla warfare. Primitive warfare is not large groups of warriors going head to head, but instead, hit and run, raids, ambushes. Even against children, as indicated above, and has been observed by modern tribal groups in New Guinea. There can be derived from the data a clear line indicating how these earlier groups of humans would have interacted from their fossils:

• 40% of Neanderthal skeletons have head injuries
• 40% of Homo sapiens burials had spear or arrow points embedded in them.
• 90%+ of known modern human societies have been in involved in war. Those that did not are often driven into isolated refuges by war
• 86% of Native American tribes went raiding or had to resist raids at least once a year.

According to Wyman, there's one set of morals for an in-group (rarely resulting in death - even in male/male dominance conflicts), but out-group conflict almost always results in death. Think, "Thou shalt not kill" vs. the subsequent conquering of Canaan by the Hebrews in biblical terms. 

Vestiges of behaviors developmentally associated with this period of violence is the need to establish higher ground - for the simple purpose of surveying the landscape to guard against raids. We can see how caves could develop for this purpose. If not living quarters, then certainly well-maintained multi-purpose camps.

What exacerbates this problem is, of course, climate change. With lesser food density, the population has to spread out. Thus, females would be less interested in males flat-out competing, but in the most resourceful. As a result, male/male competition was reduced. Females reduced and eventually ceased their display of estrus (heat). Estrus attracts the most dominant, but the lack of it attracts the most intelligent:

"If he knows when she is in estrus, he also knows when she is not in estrus - and when she's not in estrus, he may have no evolutionary push to stay there, but to go out and try to find some other female. The purpose of not showing your estrus may be to keep the male uncertain of when you are fertile, and therefore, he has to attend to the female all the time... She's no longer interested so much in male competition, but in whatever resources the male can bring to her by having a male around continually. ....an increase in the male contribution to child rearing is one of the major reasons for the increased fertility of humans"

_Robert Wyman, Yale

Human females can reproduce four-five times faster than chimpanzees. It would appear, this is a result of environmental pressure and threat of real extinction of our genus - a bottleneck. For, in these refugia, it's very easy for a small population to go extinct. Our genome, even stretching back to Homo heidelbergensis as we can detect, indicates repeated occurrences of bottlenecks. The most recent being experienced by Homo sapiens at 74kya, due to a volcanic eruption of Mt. Toba  in Sumatra, with global consequences. Through various Milankovitch cycles, extinction of our genus Homo was always a very real possibility. And juxtaposed to these events, within the human genome, is evidence of a rapid evolution - adapt or die - just as in Australopithecus garhi adapted into Homo habilis, and habilis evolved into Homo erectus due to climactic pressures. And evolving rapidly denotes a struggle with the environment. When the relationship with the environment is optimized, evolution slows down. So, "mutations that occur in population bottlenecks spread rapidly within the decreased population," says Wyman.

Thus, some regions or refugia would be ahead of others in the process of evolving into our species. The record of bones indicates East Africa and Southern Europe, certain apomorphies (traits which characterize and ancestral species and its descendants) began to make their appearance in the descendants of Homo erectus ~800kya. While, these same recognizable changes would not occur elsewhere in the world until around ~400kya. As these changes are taking place rapidly in some populations and gradually in others, between 1.2mya - 800kya it becomes difficult to classify different species of our genus. We find traces of erectus in what we would morphologically perceive to be Homo heidelbergensis. 

This map also indicates countries in some ways intolerant to archaeology. There's a wide gap spanning from W. Africa to the Far East. In modern times, these countries are either more conservative, in political strife, or religious states (India is the exception and Pakistan does contain significant sites not listed here). A wide chasm thus remains in the understanding of our species history as a result.

Then again, during and after a period of rapid and diverse morphological changes, some 400ky later, we find traces of heidelbergensis in the birth of Homo neanderthalensis - as evidenced in the fossils of Atapuerca, Spain, in a site named Sima de los Huesos, or "The Pit of Bones."

"The Pit of Bones," is the first known burial site for any of our hominid ancestors. This place was repeatedly occupied between ~850kya - 400kya. It is a cave shaft of 43 ft in depth, at the bottom of which lies the remains of 28 Heidelbergensis. The morphological remains span from skeletal types of Homo erectus morphing into Homo heidelbergensis in the more ancient specimens, and Heidelbergensis being shaped into Neanderthals in the more recent layers. It is also the first evidence of a "symbolic burial" - a decorative handaxe was found next to one of the remains. These people must have had some sense of deep care and memoriam of their loved ones, and perhaps even an afterlife. 

The "cladistic-refugium" effect can account for any speculation on the admixture of these remains. For comparison, the earliest fossil of Heidelbergensis is Mauer mandible (jaw bone) found in Germany in 1907. The majority of the community agree on classifying this ~600kya fossil as a distinct species. Most importantly, we can bridge toward understanding them as morphologically distinguished out of an erectus lineage, ~621kya - 500kya during a "prolonged warm and humid"(Chen and Yu, National Taiwan Ocean University) period of Middle Pleistocene interglacial. As a reference, we're living in a warm interglacial now. Collective data such as this, along with genetics suggest a bifurcation into Homo sapiens and Neanderthal >530kya. But examined separately ("The Status of Homo heidelbergensis," Chris Stringer, Professor at London's Natural History Museum):

• The draft of the neanderthal genomes puts divergence between 440kya - 270kya.
• Complete mtDNA (matrilineal genes) sequences suggest 538kya - 315kya.
• Morphologic (fossils) specimens range from  592kya - 182kya.

Include these data with the range of occupation at the Pit of Bones and we could at least detect a solid range of Homo heidelbergensis morphology. We can even logically consider that more than one species may have co-existed or overlapped in time. Chris Stringer reports that this range, "can be viewed as an early date for Neanderthal characteristics... instead coexistence on the basis of late Heidelbergensis age estimates. Sima de los Huesos displays a mosaic of heidelbergensis and neanderthal features." The mandibles (jaws) resemble Neanderthals, but the craniums don't match in morphology.

The beginning evolution into Heidelbergensis out of Erectus is placed near ~1.2mya. The global climate of this time was shocked by a rapid glacial onset. Onto 400ky later we see another warm interglacial - and the distinction into Heidelbergensis start to realize. If we include them within the periods between 1.2mya - 500kya, then we should logically view them within what is called Middle-Pleistocene Revolution (Head & Gibbard, University of Cambridge). At 940kya, a significant Ice Age, and within 90ky afterward we see the first Heidelbergensis site, or settlement as we currently know. "These climate

transformations, particularly the increasing severity and duration of cold stages, have had a profound effect on the biota and the physical landscape, especially in the northern hemisphere." (Head & Gibbard 2005) With interglacials on a virtual +/-100ky cycle,this is the span of time when these refugia would have progressively aided regional speciation in refugia. 

Around this time frame, we also find the emergence of the newly discovered Australasian Denisovans. Due to introgression, 17% of its genome is a product of inter-breeding with Neanderthal. We tend to associate this group with Neanderthals as their tool-making industries overlap in western asia. From W. Siberia, SE Asia, Melanesia, as far east as the Philippines, and as far south as Australia 4% of the human genome of today is Denisovan. This species, based on genomic research, was entirely distinct from any other form of human. We share 33% less genetic similarity with them than with Neanderthals; that it had more diversity in its time and more longevity within Eurasia than Neanderthals.

From fossils found, we can deduce that it shared no other morphological traits with coexisting or extant humans. 

What we do know is that we can't identify the genetic origin of ~2% our DNA, though we know it is an extinct member of the genus Homo. That it introgressed into our genome ~35kya, that also split from its ancestors around ~700kya (Hammer, et al. Institute of Human Genetics and the Univ, of Arizona 2011). 

So, the Pleistocene Epoch spans from 2.5mya, and the emergence of Homo habilis. Within the the first stage, named the Gelasian, marks another strong and severe ice age, followed by interglacials and an evolving species. Next, from 1.8mya sees the emergence of Erectus, and its global migration. Why I personally believe Homo erectus was so successful in its development is the time periods of these interglacials. Glaciation obviously forced a contraction. The contractions not only affected these humans, but all flora and fauna thus environed. The onset of the aforementioned Mid-Pleistocene Revolution (1.2mya -500kya) expanded these interglacials. Before 1.2mya interglacials had a cycle of 41kya, and since 1.2mya the cycle has been glaciation every 100kya. The climate became more chaotic and unstable hereafter. An example of our current interglacial:

Through sharp, abrupt and periodic ice ages, followed by long and unstable interglacials, then in 100ky cycles interrupted by even more severe ice ages, these humans were driven into refugia that could buffer them against climactic instability and did serve as evolutionary incubators in developing adaptive mechanisms. Brain size increased to, and in some cases overlapped, the volume of modern humans. Thus, these smaller populations would mutate faster. And during interglacials would, at least a measurable percentage of the time, interact and introgress with other hominid species - hybridization events:

"When a lineage adapts a new (or changes its) refugial area, and it survivs for a number of Milankovitch cycles, expanding from and contracting into the new refugium instead of its original one, it is destined to evolve into a distinct population. Given enough time in isolation, it will be come a new species....a new refugia is unlikely to have the same flora, fauna, or ecology compared to the lineages original refugium, which contributes selective pressure to adapt and diverge." _Steward and Stringer 2012

This explains the wide range of morphological characters and clades at shared and spanning regional sites.

Milankovitch - Glacial  - Speciation Dynamics (Quaternary Glacial, Wikipedia)

At 780ky is the abrupt shock into the Calabrian Stage of the Pleistocene.

Sometime around 781kya, the magnetic poles reversed and caused an ice age that introduced a cold and dry climate globally. Thereafter of 781kya - 126kya, we have the definitive emergence of Heidelbergensis, the progenitors of Denisovan, Neanderthal, and Homo Sapiens. 

Euro Heidelbergensis

Between 500kya and 300kya, Heidelbergensis experiences a period of gigantism. Some South African fossils are from individuals that were routinely over 7 ft. As did other secondary grassland-dependent animals grow in size.

The Elephant with Homo erectus is similar to that of cows for Americans. But, less of a dietary preference, and instead, a dietary dependence. At it's birth, there were 12 species of pachyderms roaming Africa and the Old World. Most of them were giants. Now, there are only two species - African and Asian - which remarkably migrated and diverged just at the time of the early migrations of Erectus. With this relationship we will begin to deconstruct the behavioral, subsistence, and environmental models associated with the rise, existence and disappearance of Heidelbergensis. 

.

The Sahara Pump and the First Wave

"No way of thinking or doing, however ancient, can be trusted without proof. What everybody echoes, or in silence passes by, as true today, may turn out to be falsehood tomorrow, mere smoke of opinion, which some had trusted for a cloud that would sprinkle fertilizing rain on their fields."

_Henry David Thoreau

The human creature is a territorial one. It is my nation, my state, my city, my party, my status, my class, my community, my race, my tribe, my clan, my family, my beliefs - all bleeding into my idea of Self. All culture is inherited. Test any of these, and you offend. Whether that territory be mental or actual - we have evolved boundaries and compartments that divide and not unite - shredding ideas of common humanity, and replacing them with status and comparison. Nothing blocks honesty so aggressively. 

So science is proving to be an elixir peeling back masks of self-identifying ignore-ance. But every breathing human matters to me like the cooling winds in heat. Every forebear is a strengthening brick or I do not stand on this day. And tomorrow belongs to posterity - not to our yesterdays, or contemporary failures. 

Stretch, reach, and grasp.

Failure to experiment, to test, to try, to go where there is no path, has literally led to the extinction of every other hominin that walked this planet before, and with, us. The only difference is evolutionary. That is an honest excuse - as they had no, little, or limited, faculty and capacity for heritable culture. They could not learn enough to adjust - in time.

In our primate cousins (98%+ shared DNA), different communities display different cultures. Whereas, one community of localized chimpanzees may use twigs to dig for termites - another may use no tools at all for that purpose, but instead use crushed leaves as a sponge to filter and soak up drinking water. Even within the troop, such knowledge is difficult to pass on, unless offspring learns it from mother. So the capacity to learn it would be genetically transferred. Still, this skill set may not spread among the troop, and definitely not out of it. The block is mental capacity, status ranking (class systems in human society) and fierce territorial aggression (my identity, my space, my resources vs. the out-group). These territories are enforced by patrolling war bands of mature males. There is zero cultural exchange with the out-group. The only genetic exchange is female seeking mates or asylum, at their potential peril, with an out-group.

And we are separated from these primates by nearly 7 million years of concurrent but divergent evolution as we know it. But social status still limits access to knowledge and capital. (the Internet is changing this) On the average, in traditional cultures the married bride enters the husbands family, hence bride prices and dowries. We have borders bounding every nation, state, county, every neighborhood and every mind.

A mirror neuron is a neuron that fires in the brain when one animal acts, and that act is observed and learned by another. In humans, I literally feel you, empathize, sympathize, and experience with you. In humans, these mirror neurons are highly coordinated with learning. We basically mimic our way to learning with more relative ease. This simplifies learning, so we don't have to discover each tedious step and build an entire mental architecture to execute one simple skill atop another one, ad infinitum. And this evolved learning architecture did not emerge in us - but in ancestors in between.

The similarities are apparent - as apparent as the differences. We are bipedal hunter-gatherers by nature. We are highly nomadic, with deeply and varying degrees of culture in its myriad inflections at every step of the way. And with each hominid line since our divergence from the common ancestor we share with chimpanzees, in successive steps, expanding our geographical range - we carried this sense of territorialism with us. 

This expansion mirrors our broadening of technology. More efficient tools evolved Australopithecus garhi into Homo habilis. More planning and design evolved Homo habilis into Homo erectus - from scavenger/small game hunters - to less scavenging/small game hunters/stealing big game from apex predators - to stealing big game/hunters-gatherers - to hunter-gatherer Apex predator like the world has never born before. So impressive, that fear of other apex predators was either suppressed or lost by courage and confidence in our abilities and tools, without a gun, but with sticks and stones, language and strategy. 

Expanded tool use would not be a reality if we lacked the capacity for heritable culture, as it is limited in our ape and primate cousins. What the modern human being is just beginning to understand is that culture is inherited, learned, and most importantly, environmentally influenced. Homo habilis was a forager, hunted small game, was a highly efficient scavenger - using stone tools as scrapers to cut remaining meat left over from big game predators, and using stones as hammers to crush bones where there was no meat, to get at the marrow within - rich in fatty acids and literally food for building a big brain. Yet, they themselves remained prey for apex predators. So what would turn a timid scavenger into a brave hunter? I would argue climate-induced starvation. 

During the axial precession (precession of equinoxes), every 26k years, the position of the Earth in its orbit around the Sun changes - causing climate change. Variations, or eccentricity, in this movement is called the Milankovitch cycle - in turn, causes climactic patterns. For example, what was once a woodland area would receive more sunlight and become grasslands, etc. This alters the entire ecological spectrum. Due to the Milankovitch cycles, lakes could appear, disappear and reappear, to varying degree over the span of a few thousand years. River would swell, shrink or dry up, then reappear. Dependent and competitive flora and fauna are deeply affected.  Food and water sources change. Animals must change with them or risk dying. So, migration routes are altered, along with the predators that follow them. These predators must stay diligent, or risk missing the opportunity to eat to stay alive. And the scavengers must follow the predators.

In your gut lives some of the same species of bacteria that resides in the saliva of lions. For sustenance, a smart scavenger should follow smart, bold predators, and lion packs take down the biggest game. Lions do not typically hunt during the midday heat as discussed in previous posts. They must give up the chase quickly or risk overheating in their pursuit. To preserve that energy, they hunt at dusk, dawn or night. Our hominin ancestors like Homo Habilis were diurnal (active in the day), just as we are. So these daylight hours would be employed for foraging, small game hunting, and scavenging.

During more than one of these dramatic climactic shifts, as migration routes/food sources changed and water sources were altered, game was certainly more scarce. The breakup of the ecological landscape would have scattered the hungry and thirsty to the four winds to search for nourishment. This scarcity undoubtedly forced lions, hyenas, cheetahs, leopards and scavengers like Homo habilis into confrontations. Predators, being strictly carnivores, being dependent on the meat, would fight fiercely for it - and fight off these daytime scavengers, who not only saw their meat sources become scarce, but their small game and plant sources of food altered. Starvation makes you bold - it is necessity that become the driver, not the aversion of risk. Recalling from a previous post - chimpanzees also hunt small game in bands. Homo habilis obviously did the same. So a cooperative hunting strategy would have been employed towards scavenging in this climate of scarce resources and confrontation. They gained courage out of necessity, and in a band equipped with stones and wooden spears, confronted the predators that would otherwise prey on them - and still did when chance permitted. They encroached not with the intention to hunt, but to scavenge on what was available in dire circumstances, and what they themselves could not take down. They no longer ran, but grouped together and cooperated for survival - boldly entering the lions camp, scaring them off, stealing their prey - and gaining/sharing experience. 

What is lost to the naked eye is the paleoclimate of these developmental, influential years. And, yet, due to science, the contemporary examination of flora fossils, ancient lake and river bed sediments, and isotopes found in soil samples, reveal these periodic climate shifts, at times rapid and other times more gradual. And the fauna records, of and around these same periods in time, reflect these breaking ups and subsequent recombinations of entire ecosystems. Our earliest bipedal ancestor found to date, Sahelanthropus tchadensis (Toumai), circa 7 million years old, was found in the deserts of Chad. Yet, in its lifetime, this was a wooded and wet, lake scattered ecosystem.

As we know, Homo erectus was the first of our genus to migrate out of Africa (keyword: migrate), perhaps as early as 1.9 million years ago. This was not a conscious exodus, but, instead, hunters following game. It was, up until recently, believed that they migrated up the Levantine Corridor (the western part of the Fertile Crescent) into Eurasia. During so, Homo erectus would have encountered, while in Africa, five different kinds of human beings:

Australopithecus sediba

Homo rudolfensis

Paranthropus robustus

Homo habilis

Paranthropus boisei

These early humans shared the African landscape with Homo erectus at the time of the first exodus from Africa 1.9 million years ago.

What would these first encounters have been like? There seems to be little evidence to support violent clashes between species of Homo, Australopiths and Paranthropus. After all, Homo habilis was used to scaring off predators at this time, and Homo erectus - evolving from Homo habilis - was an even more aggressive hunter. Some of the fossils of these species are found side-by-side at site and in the same geological time frame. The Paranthropus line had no technology, no tool-use, and was restricted to woodland areas with limited flexibility to a diet only containing grubs and plants. These gorilla-like hominids are found in the same areas of Homo erectus - whom, we know, was not restricted to any environment - like Homo sapiens afterward. Paranthropus also ate more plants, particularly leaves, more than any other human ancestor. It evolved from, and temporarily co-existed with, Australopithecines, like sediba above. Grasslands have proven to be home to Australopiths, yet their bone structure suggests that, though they were bipedal, tree climbing was still a prominent aspect of their lives. Examination of their dentition (micro-wear on the teeth) indicates that they ate fruits, vegetables and tubers. Being a frugivore (fruit eater) means, of course, that it would be highly dependent on the abundance of fruit - therefore trees. So this early bipedal human (think Lucy) held onto it climbing adaptation abilities as expressed in its anatomical structure. 

Here, the hominids in Africa are varied (pre-migration, pre Homo sapiens)

Thus, it would seem, there would be very little need for competition with Homo habilis and Homo erectus. And, Paranthropus and the Australopiths would be sensitive to climate affecting their habitats. And being closer to other apes than the genus Homo, also means heritable culture would have been at issue. Yet, to me, it is not a stretch to assume Homo erectus would have been, not only aggressive, but predatory. There is evidence that it hunted and ate giant baboons - as chimpanzees hunt and eat monkeys, as humans eat "bush meat," like monkeys and other apes.

In the geologic record (Pliocene Epoch) preceding the evolutionary emergence of Homo habilis, there was more climactic stability. Yet, around 2 million years ago, a rush of climate change and instability put pressure on these other hominins. A drying out of the woodland areas in the Great Rift Valley, and general eastern Africa for that matter, would've shrunk the canopy of which these frugivore australopiths, and the mostly herbivore paranthropus depended. This instability lasted for another 1.5 million years. Despite living alongside more technologically advance humans, with inherited and learned material culture, over the course of these unstable 1.5 million years, our early human relations died out. Heritable culture is what distinguishes and aids the survival of our genus Homo. But we can thank the australopithecines for acquiring stone tool use, and expanding mental capacity. So, rather abrupt environmental change seems to be the culprit - which we will examine further. They lived right alongside us. But, I believe this same climactic shift that began to put pressure on australopiths and paranthropus, also affected and scatters all other flora and fauna of this period.

And Homo erectus chased this game wherever it could - right into a green, wet Sahara of 1.9 million years ago, and eventually, out of Africa. And into a much wider geographic/ecological range - from Israel at 1.7 million years ago, Dmanisi, Georgia (Russia) at 1.8 million years ago, Pakistan at 1.9 mya, Spain of 1.7 mya, and China at 1.7 mya. 

The cyclical Milankovitch cycle effects are also observed in the soil samples from Pakistan. The oldest known humans outside of Africa are these Asians. Homo erectus in China is believed to be the earliest use of controlled fire on Earth (1.27mya). And once out of Africa, they had no other humans to displace - only game to encounter. And these encounters are not one-sided - they hunted, fought, and quite often lost. Circa 2/3rds of Homo erectus fossils in China have puncture wounds on the skull from predator canines - perhaps from giant hyenas, also chasing game out of Africa, as hyenas are known to go for the head first during the hunt. Yet, in India, a different story - fossilized remains details wounds on Homo erectus from hunting big game. So this first incursion into worlds outside of Africa were violent battlegrounds between competing apex predators - to which we were not quite yet at the top. So, buried in our genetic memory, is a real deep feeling of a need to conquer nature - to eat or be eaten (later expressed in religion as we shall see). Homo erectus was alone outside of Africa for nearly 1 million years. 

The driver of a green Sahara of 1.9 million years ago was the precession and Milankovitch cycles. And these cycles, once again, dried the Sahara not too long afterwards, blocking further migration for these 1 million years or so. Supporting this theory is evidence of evolving tool use in Africa by Homo erectus, and stagnated tool use outside of it. Whereas the Homo erectus in Africa, dubbed Homo ergaster at this time, continued to evolve their tools into Acheulean,

Homo erectus in Asia remained using Oldowan stone tools for these 1 million+ years, as evidenced in sites during this period in China, Dmanisi, India, Israel, and Pakistan:

Whilst the earliest appearance of the more evolved Acheulean stone stools in appear in Africa at 1.6mya, in India 1mya, and Europe some 800kya. 

We will revisit the Sahara Pump Theory - it plays a significant role in human history up until 6kya (when it's migrating culture founded the Egyptian culture) - and it will again in the future.

The Pleistocene Epoch is a geological period of time dating from 2.5mya up to 11kya. For humans, from the emergence of Homo habilis to the earliest known use of agriculture. It is characterized by repeated cycles of glaciation (Ice ages), and would have ended with the last Ice Age we are all so familiar with and associate with "cave men." It is the most significant period for the development of modern human beings. Our accepted species, Homo sapiens sapiens, was born in the Pleistocene. My proposal is that Homo techne is what we are currently, and still currently speciating (slowly changing into a new species) in the now present Holocene Epoch. But the Pleistocene is this remarkable time span when we evolved to become recognizably human - from Australopithecus garhi to the accepted widespread employment of sedentarism and agriculture by Homo sapiens. 

The Pliocene Epoch (5.3mya - 2.5mya) that preceded the Pleistocene was on average 2-3 degrees centigrade higher than today - with global sea levels 25m greater. The sudden cooling at the end of the Pliocene would have brought the disappearance of fragile forests and the spread of grasslands - beginning the Pleistocene and forcing Au. garhi and Homo habilis into environmental pressures that they had to adapt to or perish. It is believed the australopiths began to die out from failure to adjust and its dependence on a narrow ecology. Yet, I would suggest, Au. garhi may, itself, speciated, or evolved a sub-species - Homo habilis. Fossils of these two species have been found side-by-side for a geological period spanning 200-300ky. As evidenced by the relative youth of Homo sapiens (195ky), this is ample time to diverge and evolve. So those Au. garhi without adequate capacity of heritable culture perished. I suspect those that did not evolved into Homo habilis - the first in the genus Homo. 

The Pleistocene Epoch, at times of extreme Ice Ages, brought glaciers down to the 40th parallel. At most, 30% of the Earth's surface was frozen, in addition to permafrost on the edges of that glaciation. The temperature along these edges would have ranged from 21-35 degrees Fahrenheit. Sea levels would have dropped a dramatic 300ft. So, just as Siberians crossed the Bering Strait between Alaska and Russia to evolve into Native Americans some 40kya+ - between these glacial periods of the Pleistocene, previous coastlines would have drowned. This stifles modern paleoarchaelogy - as most migration routes would be underwater during our current, warmer Holocene Epoch. 

But glaciers were not unfamiliar to our human ancestors in Africa. Mt. Kilimanjaro, Mt. Kenya, mountain ranges in Ethiopia, and in east/central Africa were covered by even larger glaciers during ice ages of Pleistocene. All glaciation, interglacials (periods in between - of which we are in one currently), periods of receding glacials, wind and ocean currents, climate and other weather factors, are all in correspondence with the precession and Milankovitch cycles. 

Now, imagine with the advancement of ice sheets - entire regions of migrating animals, populating new areas, and depopulating others. Those animals in the North, like in Europe, would be migrating South into the Levantine Corridor, the Middle East, Northern Africa, and the Green Sahara. 

"Greening" would increase and decrease depending on the degree of monsoonal rains (pluvials)

Animals affected by increased African glaciation would be migrating North into the Sahel (Arabic for "coast") - the Southern part of North Africa between the Sahara and the Sudanese savanna (east to west from the Atlantic to Ethiopia).

So what would make the Sahara turn green? 

Heat. Yes, more heat. More heat is more evaporation - evaporating ocean water is more rainfall - extended periods of rainfall are called pluvials. These "pluvials" feed into the West African monsoon seasons. These extreme monsoon seasons equals larger lakes and swelling rivers - cyclically reactivating a "green" Sahara. Later, this glacial excursion, inter-glacial warming and pluvial downpours would fuel the Natufian culture in the Levant to sedentarism and agriculture between 30-11kya. 

These Milankovitch fueled pluvials - from the monsoonal systems in subtropical regions - affected not only Saharan Africa, but desert Arabia, India and Pakistan. 

Thus animal migrations southward to escape glaciers and northward in Africa due to disrupted ecological communities - into the Sahel, then the Sahara, then into the Levantine Corridor (later, the "Garden of Eden" along with Mesopotamia), then Arabia, followed by India and Pakistan - were followed by the first hunter-gatherers Homo erectus.

Still, for a million years after the First Wave of human beings out of Africa - the Sahara desert returned, and stayed dry. In my view, the Pleistocene Ice Ages, monsoonal pluvials and the Sahara Pump Theory have more credence than the Levantine Corridor as a migration route out of Africa on its own. It explains, geologically, the stagnation of Oldowan technology outside of Africa - no cultural, heritable exchange for a million years - while Acheulean was sparked within Africa. These peoples were still capable of learning and evolving culturally. Recently, in 2013, stone tools found in India, of the Acheulean kind, were originally dated to between 1.1m - 800kya. Yet, a recent dating of these very same tools suggest a new time period of circa 1.5mya - a mere 100ky after known Acheulean emergence in Africa, and when the Sahara Pump would have been dry blocking further migration out, or back in. But glaciation does not necessarily correlate with monsoonal rains in tropical parallels. But it does correlate with lowered sea levels and land bridges further exposing the Levantine corridor. Or - these Homo erectus. were simply smart enough to continue to evolve, being culturally isolated - as it would seem. But, we do know, the First Wave, was a result of the Sahara Pump - and undeniable evidence comes from Homo sapiens rock art during the last known green Sahara:

Rock art depictions of cattle, camels, and people in the Sahara region of Chad offer evidence that humans and animals once occupied this area. At the time rock art was done—from the fifth to the second millennium B.C.—the area was an open savanna, which supported the animals represented in the rock art.

Despite recent conjecture, intelligent as they were, I doubt Homo erectus made use of rafts and/or boats to reach distant and isolated islands. At least not before their co-existence with later species of our genus Homo, like Homo sapiens, and further employing their capacity for heritable culture.

It only takes an Ice Age to lower the light blue sea levels and turn them into a Land Bridge - ask the Aborigines

Repeated glacials (ice ages), would have provided over 1 million years, ample time for Homo erectus to reach Java in Indonesia. Homo floresiensis (the Hobbit) is a dwarf sub-species of Homo erectus that survived on Indonesia as recently as 18kya. Stories of giants and dwarves are embedded in our ancestral memories - informing oral traditions with sights that early Homo sapiens encountered along the last major migration of our genus Homo. 

So paleoclimatology (the study of prehistoric climates) is vital in understanding, not only what shapes us, but what moves us. Literally.

During the time of Homo habilis, shelter was nest-like, atop a cliff, or under a fallen tree. A cave is widely considered too dangerous for a prey animal like Homo habilis, and the environment was considerably warmer in the Late Pliocene and early Pleistocene in Africa for the "Handy Man." Yet, as they had a tool-making industry, and employed in primitive (read early) human hunting strategy - they would undoubtedly and repeatedly make use of the same shelters. But, critical here - without the persistence hunting strategy employed by Homo erectus, they would have held onto their chimp-like body fur.

When Homo erectus migrates out of Africa, we have evidence of shelter construction. In northern Israel, at the site of Gesher Benot Ya'aqov, a Homo erectus encampment of 750kya has been unearthed. The camp was planned and laid out according to divisions of labor and utility. For example, a hut for butchering, a hut for processing gathered items, and another for processing fish. (Fish processing at this early site changes what we first thought about early humans fishing - it was widely believed Homo sapiens began to do so more seriously around 109kya in S. Africa.) Situated on a Pleistocene lake-shore, it would be the oldest example of fishing ever discovered. But I postulate, that shelter construction by Homo erectus had to evolve much earlier for them expand this shelter building skill set into building specialized camps nearly three-quarters of a million years ago. First, as it gradually lost it's fear of predators, and perhaps in tandem with refined and controlled fire use - they conquered their fear of caves. This is the first so-called, "cave man." A significant portion of fire hearth remains, butchered animal remains, and stone tools were found at, or around the mouths of caves. But, this was hardly a "cave man." Researchers believe these caves were more camps than homes. Also, where there are no caves - there's still Homo erectus. To better understand the evolution of the home and construction of shelters - we should revisit Homo habilis' fallen tree shelters; bearing in mind that, if Homo habilis could gather choice stones for tool construction, then, presumably, they can gather branches and sticks for shelter enhancement - perhaps, even, utilizing tools to cut, chop and shape them while doing so.

From a fallen tree with a few branches for blockage.

To a fallen tree with more branches and plant/mud debris for deliberate construction.

To deliberate construction with fully resourced materials

The first two hardly seem like a stretch for Homo habilis. And the last, though a modern day hunter's shelter, is not far off from what Homo erectus would have been capable of. Yet, since Homo erectus was not limited to just wooded environments, and was the first hunter-gatherer, their shelters in grassland areas would have utilized large game bones for support and hides for wind-breakage. They would've taken the Homo habilis technique a step further - for two identifiable reasons: refined tool use, and environment/material considerations. They gathered large branches, or bones, for structural support, instead of simple cover, like Homo habilis. They dug holes in the ground to set them in, and would arrange them in a circular, or oval, fashion, overlaying them with either leaves, or animal hides - and leaving a hole in the top for smoke to escape from the fire in the center ground, in the middle of a circle of stones - the fireplace.

So shelter's for Homo erectus were built around fires. Home is where the hearth is. Hearth, literally means "burning place," and its older than the home itself. The words "heart" and "hearth" both have an original meaning of "central spot." And, fire use is, more than likely, 1.27 million years old.

It most be noted, that migration out of Africa through an open corridor or Sahara Pump is not limited to an exodus - but also, of Homo erectus hunting game back into Africa. (We have, and will continue to discuss this introgression) And that this evolved form of shelter may have been an early ice-age necessity for a creature that evolved in the warmer East Africa and perhaps brought this advancement back into Africa with them. But, again an examination of climate is at hand. East Africa is less of an equatorial climate due to its higher elevation and monsoonal rainy seasons. Whereas, in other areas of East Africa, like Rwanda and eastern Ethiopia, it is more tropical. In certain places, it is drier and cooler than one might expect - places like Somalia and Ethiopia experience tremendous droughts to this day. The eastern coastal regions would be hot, but more inland, considerably milder. And though there are glaciers at higher altitudes atop mountains - it would not have compared to the glacials near the 40th parallel during an extreme Ice Age, which would force the disruption of flora and fauna nearly the world over - cyclically, repeatedly throughout the Pleistocene.

Thus, as we'll see with others of the genus Homo that evolved from Homo erectus -  Homo heidelbergensis, Homo neanderthalensis, Homo denisovans, and Homo sapiens - further research suggests that Pleistocene, ice-age humans, ancient and new, hunted big game against the ice sheets to limit escape routes. In whole regions of 27-35 degree temperatures, for a hominin that evolved in dry and/or wet, yet typically warmer Africa, perhaps even these animals skins were a necessity for bodily warmth. Yet, there is little evidence to suggest this. But, in my view, this is a glaring absence of culture in correlation with the environment they faced, and in which they had not evolved to survive. And, if persistence hunting brought upon the evolution of more sweat glands to cool in the midday heat, then shelter and clothing in multiple Ice Ages would further eliminate the need for fur. Without making use of these same animals hides for clothing - how could they not have perished in this new, icy and hostile frontier?

The most compelling argument against clothing at this time is the genetics of body lice associated with us humans. The head lice diverged from body lice circa 107kya, according to genetic studies - suggesting that clothing would be no more than 100K years old for Homo sapiens. Yet, we know, Homo heidelbergensis and Neanderthals both wore hides and fur in the drastic cold of their Ice Age environments. Neither were the first to face the severe cold of glacials. And if Homo sapiens has evolved superior capacity for heritable culture in comparison to all previous hominins - then, in my view, when our species was born - clothing was already utilized by others of our genus - if only in environments where necessary.

The Sahara would again turn green circa 1.1mya. And during the second wave of migration out of Africa brought on by the Sahara Pump, Homo heidelbergensis would follow its evolutionary parent, Homo erectus.

Heidelbergensis in Europe evolved into the Neanderthals in Europe and the Middle East, and into Homo denisova in eastern Europe, Asia, the islands of Micronesia, Indonesia and New Guinea. Heidelbergensis in Africa would evolve into...Homo sapiens.

Homo Techne- there is a detectable trajectory here. That there is a feedback between environment and response. That if you respond with invention - you can cope with environment. At every step along the way thus far, the population, and thus, the geographic range of our ancestors increased. With that population increase came inheritable culture. That culture brings a fertile ground for the birth and nurturing of shared ideas. Those ideas turn into invention. Those inventions turn into a milieu of technologies - begetting evermore.

But cultural isolation is generally not by choice, but external, climactic circumstance in these later lines of our ancestors. We will see with later additions to the genus Homo how and when isolated cultures, beliefs and even races, begin to develop into the myriad examples reflected today. We will see how environment influences all, how we've always used technology to cope, combat and endure - and how introgression is as cyclical as the earth's revolutions - hence, today's "globalization."