Edgar Rice Burroughs’s (ERB) Martian (Barsoom) novels, although they take place in “the present”, describe current-day (circa 1866 to 1941) Barsoom as being preceded by a long march of history going back one million years to a vanished maritime civilization consisting of white (the “Orovars”), black (the “First Born,” at least in “modern” times), and yellow (we’ll call them the “Okar” or “Okarians” etc., also at least in modern times) peoples. ERB frequently tells us that ancient Barsoom flourished one million years ago. This ancient civilization ended as the atmosphere thinned and the oceans evaporated, to be replaced by the rise of the red Barsoomian civilizations and people. All that is left of this vanished civilization are dead cities and legends, plus a few anomalous hidden remnants touched upon in some of ERB’s novels1 and fan fiction.
Although ERB never wrote stories that took place within this past history, there have been a few fan-written stories published on the Web2 that do so, apparently at the implicit height of the ancient Barsoomian period. It is intriguing to consider the stories yet untold from these ancient times, to include those from the never-documented long fall of ancient Barsoomian civilization. Did these people understand what was happening as the oceans receded and the atmosphere thinned? What did they try to do to stop or slow the death of their civilization, beyond building the canals and atmosphere factory, and ERB’s occasional reference to newer portions of their cities being built to follow the receding waters? Did they go quietly with dignity into oblivion, did they approach it with mindless terror, or did they fight the fall vigorously with intellect and muscle? We'll try to fill in some of the gaps in this history as we trace the deterioration of ancient Barsoom, based on our ideas but also building upon the ideas of others (conveniently found within ERBzine3). We'll also have some fun doing this!
ERB’s Martian novels contain a good degree of science not founded in currently accepted fact. We can agree that ERB did the best he could with the knowledge of his time, and was focused more on telling a good story than scientific accuracy. Some of the questionable items he includes are:
He also ignores some of the usual vagaries of life:
- Life as we know it on a habitable Mars!
- Egg-laying humans
- The 8th and 9th rays for aircraft buoyancy and atmosphere production, respectively
- “Radium” as the component of proximity-detecting guidance systems, explosive projectiles and lighting
- An astonishing range of four and more than four-limbed body plans
- Climates and ecosystems that simply don’t match up with our current knowledge of Mars
- Storage of the sun’s rays for various purposes
- A general timeline for civilization that goes back a million years or soWe shouldn’t let facts spoil having fun with the Barsoom he created, nor should these facts bar us from creating new stories. In fact they can help us make the telling that much more interesting. We may also indulge in a little weird science ourselves in the process of doing so. It’s also interesting to note where his stories align fairly closely with reality – his descriptions of geography, for instance, have been aligned with modern astronomical observations5. We’ll leverage some of these alignment observations below. For example, it’s been proposed that the Northern Hemisphere of ancient Barsoom was largely covered with ocean, due to its lower overall elevation, with most of the habitable land in the Southern Hemisphere. We also have another area to address regarding science. From today’s viewpoint (but not necessarily ERB’s) the ancient Barsoomians were civilized for many thousands, possibly tens or even hundreds of thousands years. Why didn’t they develop a technological civilization and simply migrate to Jasoom (Earth)? To our Western civilization/"Jasoomian" view they must certainly have had sufficient time to do this, since after all, we went from the first powered flight to the Moon in 66 years. There certainly were other authors writing about space flight who were contemporary to ERB6. Did it simply not occur to them, or was limited space-flight achieved and then lost or suppressed?
With one exception4, no mention of weather and season other than his mention of hot days and cold nights. Not much is said regarding disease.
What Caused Barsoom's Oceans and Atmosphere to Deteriorate?
Let's talk about the Barsoomian atmosphere and oceans.
We’ll start with some basic physics. Retention of a stable atmosphere by a planet is a function of a delicate balance of temperature and gravity. Pressure, at the thermodynamic level, is a function of the motion of individual molecules of atmospheric components, which increases when you heat these molecules. Gravity pulls on the molecules and keeps them from caroming off into space. Some do7, but as long as their energy is below a certain level, and the gravity above a certain level, a stable atmosphere can be retained. If the concept is unfamiliar think of lots of rubber balls bouncing around in a room – they occasionally hit each other. Now if there is an open window occasionally a ball will escape. Increase the energy of the bouncing and the statistical likelihood of more balls escaping goes up.
We can assume that this balance was much more delicate for ancient Barsoom than for our Earth. In fact, let's assume that a slow loss of atmosphere and water was already occurring, but at a slow enough rate that changes were only noticeable over a geological time scale. Remember this point...
Let’s talk about “greenhouse gases.” Greenhouse gases, primarily carbon dioxide (CO2), cause greater retention of the Sun's heat, which over time will cause subtle increases in global temperature if these gases were to increase in the atmosphere. Plants metabolize CO2 back to oxygen (O2) – this is part of what ecologists call the “carbon cycle.”
Let’s also assume that the volcanoes of the Tharsis Montes region were periodically active in ancient “historical” times (Weird Science Alert! The latest scientific thinking is that they were actually last active 40 million years ago). CO2 is a major product of volcanism. (There would probably be much said about these volcanoes in this religion too – there’s a story in there.)
We can assume that the early peoples of Barsoom probably, as they evolved from primitive hunter-gatherers to agriculturists, began to burn off forests to obtain more croplands. Fire also generates CO2. This burning would both increase the amount of CO2 and reduce the amount of plants able to metabolize CO2 back to O2.
So, the situation we have is that, as population rose with increasing civilization there was an ever-increasing need for more cropland, which necessitated increasing burn-off of the forests. We have the atmosphere of ancient Barsoom getting loaded up with greenhouse gases while the ability to remove these gases is being decreased. Thus, ever so slowly, Barsoom began to warm up. Not by much, mind you, just a few fractions of a degree. However, that's all it takes for changes to start to occur.
Thus, the ancient Barsoomians sealed their fate. Forest burn-off upset the balance. The increase in CO2 caused more heat to be retained by the atmosphere, and more atmosphere would begin to escape into space. At the same time, O2 production from vegetation goes down. The atmosphere begins to thin. This thinning would be disproportionate to the composition of the atmosphere – the lighter molecules (O2 and nitrogen) would go before the heavier molecules (CO2).
So what about the oceans? The Barsoomian temperature elevation would impact them also, causing some subtle changes here too. Similar to the atmosphere, liquid water actually exists in an equilibrium with its other physical states, so there are always some water molecules existing in the gaseous phase present. We commonly call the transition of liquid to gaseous water that occurs at temperatures comfortable to us "evaporation" -- this increases with increasing temperature until we reach a point where we are boiling the water, and the equilibrium significantly favors the gaseous state (to the chemists in the audience – we know we’re simplifying this a bit). Where this gets really interesting is at higher altitudes (lower air pressure). Try boiling water at higher altitudes and you'll find that it boils at a lower temperature -- some things like hard-boiled eggs are much harder to cook because that transition of liquid to gas is occurring at a faster rate at lower temperatures. At a low enough pressure water can actually go from ice to a gas – sublimation. Therefore, similar to the atmosphere there is also equilibrium here, although it's more affected by temperature and pressure than gravity, although once gaseous these water molecules would then be subject to the same behavior as other atmosphere components. So, after a while, water would begin to evaporate and slowly escape into space.
Is evaporation enough to account for the loss of the oceans? Probably not – there were likely some other factors at play here. For example, we believe today that there is considerable subterranean ice on Mars – undoubtedly some fraction of the ancient oceans might have ended up in this form.
The ancient Barsoomians, in an attempt to forestall their fate, may have actually accelerated their doom. Would knowledge of the worsening conditions have triggered a religious or intellectual revolution that attempted to explain or understand the collapse? Could they have experimented with electrolysis to produce oxygen from water? Might a form of alchemy have arisen (Weird Science Alert!), focused on binding water and air into preservable and stable forms or even creating more? Likely “yes,” since we know that at some point the ancient Barsoomians built the atmosphere factories. What false starts and mistakes might have been made along the way that actually accelerated the collapse? Is the scarlet and ochre vegetation a result of this? Did arcane chemistry result in the runaway binding of oxygen with iron to form ferric oxides (and analogous compounds with other atmospheric components?) Is water preserved as subsurface hydrates or in some arcane chemical form? We’ll assume some of this happened, even if we again cross over into weird science.
So we have a plausible “smoking gun” for the Barsoomian environmental and ecological collapse. Increased CO2 caused global warming, raising the temperature of the atmosphere to a point where the equilibrium that kept it stable was broken. O2 partial pressure went down at an accelerated pace relative to heavier components such as CO2. Somewhere in this first phase the more delicate ecologies would have been disrupted – sessile marine forms like corals, for example, would have begun to die off early. Food chains would begin to be disrupted. As atmosphere loss accelerated at some point so did evaporation through natural and man-made processes, with the result of the oceans receding and ultimately disappearing.
We’ll describe a proposed Barsoomian history using milestones along a somewhat arguable timeline to the present, leveraging the science and pseudo-science described above. Where we can, we’ll try to propose a few explanations of how we got to “present-day Barsoom,” and illustrate the changes with a few maps.
1. 1-4 Billion years ago
We can begin with the emergence of life on Barsoom. Early Barsoom (and the other early planets) was subject to massive meteor strikes (called the “Late Heavy Bombardment”) and tectonic activity. These meteor strikes created the great rift valleys or other relatively isolated zones, which could have served as isolated “test tubes”for the evolution of life in different patterns during an era of a much warmer, wetter climate.
Two or more lines of evolutionary patterns (parallel body plans) developed in isolation: the four limbed (e.g. humans) and the more than four-limbed (e.g. green men, thoats, calots)8, 9. We can suggest that the multiplicity of limbs (up to 10!) was either size-driven or were the more “primitive” forms, and that many other forms were mutations from that pattern. We can also assume that combinations of egg-laying and live-bearing body plans were also present and mixed in here somehow10.
Over time, these isolated zones eroded sufficiently that life emerged from them, spread out, and re-colonized and competed with each other. Also over time, Barsoom began to dry; geological activity lessened. The atmosphere began to thin and protect less from solar and other forms of radiation; thus more mutations occurred which increased the rate of evolution.
Much time passed…
2. Millions of years ago
We can envision here a lush world whose ecosystems are complex and teeming with a wide variety of life on the land, in the air, and in the seas. The world is still moist although continuing to dry slowly, and slow drying continues to drive evolution and land-borne migration. The volcanic highlands of the Tharsis Montes region were still active, and few men chose to live in this desolate place.True men evolved from a non-intelligent four-limbed ancestor -- presumably a primate of some sort. These true men may have been live-bearing instead of egg-laying. The primitive green men evolved through a path of convergent evolution from a non-intelligent egg-laying six-limbed ancestor. The kaldanes evolved far inland, possibly from a crustacean-like progenitor, and were segregated. Over time, wandering tribes of hunter-gatherers evolved to agricultural settlements to city-states to nations as slow drying and atmosphere loss continued to occur. Some history of this time was lost due to incessant war between wanderers, green men, and primitive villages. Many settlements reverted back to wandering as they were destroyed and their populations integrated back into wandering society or were enslaved by green men. Agriculture became more critical to survival, and, where necessary, there were burn-offs of forest land to yield more space for crops and also to drive back the hostile life of the forests (e.g., siths). Slowly the settlements got larger, wanderers got fewer, sophistication for agriculture and mariculture increased (and it needed to), and populations increased, with city-states forming based on trade and mutual defense relationships between their component settlements, villages, and towns. Some competition and war between city-states for land occurred, but also cooperation between them against the green men.The less numerous green men were always in the background as a destabilizing force and a driver to the true men evolving to a more organized culture. Indeed, the green men predation on the true men forced isolation of early men that caused the differentiation into races and the initiation of civilization. We can plausibly imagine that each race was molded by this isolation in different ways:As urbanization increased so did trade. Early development of the bow leveled the playing field with the larger and stronger green men. The bow, combined with stone axes and knives, were the primitive weapons of choice. Stone Age weapons eventually began to give way to copper, bronze, iron, and then steel swords, likely short swords in this ancient era. The bow, evolving from stone to bronze to iron tipped arrows, was the weapon of choice. Spears may also have been used.
The black race evolved from men driven into the hotter southern desert regions around inland seas and moisture traps. They early on evolved a strong martial tradition and cunning to enable them to meet the green men on an equal footing – mobbing individual green men along with a vicious campaign of egg hunting and destruction. This combined with protected safeholds in valleys served to provide the black race with sufficient protection to begin to civilize. The yellow race evolved from men driven into the hostile and often snow-covered mountainous regions around the Tharsis Montes. The yellow race used simple isolation to reduce the menace of the green men. With the yellow race living on the inaccessible mountains, the green men had little incentive to seek them out in this inhospitable environment, and were readily dealt with in the border regions again by the strategy of mob attacks. The white race evolved from men congregated around the rivers and shores, and were driven early to develop water travel that proved to be an enabler of civilization in addition to being a strategy for survival. Spreading across the offshore islands proved to be the ultimate protection from the green men, who could not follow and lacked the ability to cooperate among themselves to build sufficient culture to develop a shipbuilding capability. Population explosion on near-shore islands forced a similar explosion in ship-building and ocean travel. Others remained on the shores of the oceans and rivers and maintained contact with their sea-faring brothers.
Population moved inland, mostly in the Southern Hemisphere, as slow drying continued. The discovery of irrigation allowed cultivation within marginal areas in the southern deserts. The need for better forms of irrigation prompted the building of small canals and aqueducts, thus permitting the southern plains to become the "bread-basket" of ancient Barsoom. Within this environment of plenty city-states and early nations would form.
Joint expeditions against the green men were another impetus for nation-forming. Standing armies were formed and campaigns executed with the purpose of fighting and exterminating the green men. The green men were never numerous because of their violent nature among themselves and because they had not yet developed social behaviors or organization for protecting their vulnerable eggs during the five year incubation period. Their eggs were thus susceptible to animal predation and destruction by men (and other green men). Much hatred toward the green men existed amongst the true men – possibly a racial memory from pre-history – and expeditions formed against the green men – the green men would retain a racial memory of this hatred, and return it in kind. Green men were eventually reduced in numbers and sometimes enslaved or even trained as soldiers (to include teaching them language), or pushed into the wild lands such as the southern deserts and other marginal areas. These expeditions would have even become stylish amongst certain social classes as the expeditions turned from war more into hunts as the numbers of green men were reduced. At some point the green survivors would start to cooperate, emulate the true men, and develop some organization of their own as a necessity to survive against the constant attacks of the true men. Some green men might even have joined with the true men.
3. 1 Million years ago
Here we provide our first map, updated from prior publications (“A New Map of Barsoom”). At this point the peak of Orovar civilization was attained11. Much maritime commerce and travel occurred, and this was the primary means for the spread of civilization, news, new ideas, etc. We have the First Born centered in the Southern Hemisphere, the Okar in the Northern Hemisphere around the Tharsis Montes region, and the Orovars on the shores of Barsoom’s oceans. Standing armies were eroded or were reduced in size (war was bad for business), and a middle-class began to arise. We might imagine mercantile nations with philosopher merchants living in luxury in their cities while the bowman/sailors/hunters evolved from the armies when there was no longer much fighting. Within the cities life was good, while the sailors and hunters met enough perils (e.g., piracy, the few remaining green men) that their population and more violent tendencies were also kept in check. Although it is tempting to compare this era of Barsoom to Rome a comparison to pre-1900 India is probably more accurate.
The evolution of civilization resulted in a population increase that required a proportionate increase in agriculture. This resulted in an increasing demand for crop land, and thus an increase in forest burn-off to create new crop lands. At some point a “tipping point” was reached, and atmosphere loss accelerated.
We can also extend our knowledge of ocean current and wind behavior on Earth to Barsoom, and postulate patterns that would have driven trade routes and population migrations. These maps should serve nicely to aid authors in developing stories of this era. Note the location of Exum at the confluence of both Northern and Southern hemisphere ocean currents, and the equivalent wind patterns. It’s obvious that Exum would be a major trading port in the maritime commerce of ancient Barsoom, as all (sea) roads led to it.
4. 900,000 years ago
At this point we can invoke the acceleration of global warming (already aggravated by the burning of forests to create crop lands). Remember that subtle balance of temperature and gravity that impacts atmosphere retention? With a slight increase of temperature we now have a slightly more energetic atmosphere -- molecules of atmosphere components will begin to move faster, and that slow loss of air to space will accelerate. The situation begins to subtly worsen.
There's been some speculation in the ERBzine about the climatological "tipping point” that may have accelerated atmospheric thinning and the drying of the oceans. We propose that this tipping point was increased activity of the hitherto relatively dormant Tharsis Montes volcanoes. Volcanoes can eject gases such as CO2 and also solid material that may be retained for long periods in the atmosphere. In this case, let's assume that just CO2 and other gases are being released at an accelerated rate. The result would bean even more elevated rate of greenhouse gases in the atmosphere, an increased rate of heating, and thus an increased rate of atmosphere loss.
This would at first be evidenced in any inhabited highlands, such as the Tharsis Montes region that we propose as the ancestral home of the Okar. We can imagine a culture with many similarities to the ancient Incas of South America, with cities at higher elevations. Some of the highest habitations would experience harsher weather and eventually even difficulty breathing. Agriculture would become increasingly difficult. The population of these extreme environments would begin to migrate to lower altitudes.
Islands such as Gathol that were the above water portions of sea floor mountains would see evidence of ocean drying first as quays began to appear to rise above the ships they serviced. Ocean shallows would have begun to become exposed. Droughts would occur in formerly fertile regions. Crops would fail, forests would begin to die, and formerly fertile savannahs would become deserts.
It would have become difficult at this point to deny the inevitable. There would have been a dawning realization of this tipping point having occurred, and that ultimately it would mean their descendants’ death. Some would have approached this with apathy, some with religion, most ignored it, others, over time, might have begun to call out for something to be done to preserve life and civilization, and been pushed into an intellectual revolution.
With the drying of the forests, wood began to become a premium trade item – restricting and ultimately ending ship-building and causing a shift from predominantly wooden weapons (e.g. bows, spears) to all metal weapons. The long sword became the companion to the short sword that had been used for ages in close-in fighting when enemies were within the radius a spear could be used or a bow could be drawn and fired. This change in weapons would make exterminating the green men that much harder, even when used by mounted cavalry to address the difference in height (the green men would eventually copy this to compensate).
At the time of realization that the tipping point was here technology was mostly at a Roman level with some exceptions (what ERB knew and his thoughts on where technology might advance). Medicine was very advanced. There were mostly cottage industries – NO industrialization whatsoever (no Barsoomian ever figured out mass production, gunpowder or the steam engine). “Radium” was mostly a curiosity at this point, but useful for lighting. There were no firearms, but catapults and ballistae could have been well understood.
We can assume that a minority of various voices for action would band together and begin working on solutions. Therefore, a great convocation to discuss ways to address the problem would be reasonable. Learned savants from all over Barsoom would have traveled to it. This convocation probably extended over a period of months or years. It was probably quite lively at times until a consensus began to be reached, or at least enough of one for action to begin to be taken.
Let’s have some fun with this – there could be some good stories here! Several decisions and directions likely arose from convocation:The black and yellow races, fewer in numbers than the Orovars, might have then begun to specialize in certain areas of technology:
A decision to increase the pace of science and engineering as any solution would derive from these disciplines An investigation into the applied use of the 8th ray, which was otherwise a curiosity. Realization of the possibility of flight, although there was a containment problem for the 8th ray that would have led to further metallurgy. Some limited success with small balloons. Applied use of the 9th ray, also otherwise a curiosity, with realization that the 9th ray actually could be used for atmosphere creation Parallel investigation of other means for atmosphere creation, such as electrolysis of water to produce oxygen Some dabbling with space travel but not considered a solution for the large scale. Gems that produced rays had to be devoted to 9th ray production An investigation into protected habitat (“safehold”) creation such as through extension of the city pits or the sealing of underground caverns and lava tubes Hydroelectric power might have been discovered, and used sparingly Flight might also have been discovered, but was probably uncommon and might have been restricted for military and inter-government communications Research to better understand ocean evaporation and air loss. How far would the atmosphere and water loss go? At what point could it be stopped? Could it be reversed? Could polar water be used? An investigation into changing the peoples and animals of Barsoom. Could changes be made so that they could survive with less air and water? Could better strategies be developed and followed-through if people could live longer, and focus a longer adult life span to solving problems?There could have been a brief further flowering of civilization due to accelerated technological progress. All of these lines of investigation and action evolved and converged into “The Great Plan” for survival. The short term plan was to move12 into rift valleys, craters, caverns, lava tubes, expanded city pits, polar settlements, the underground sea of Omean (created from an existing water-filled cavern) – all moisture traps. Either depth or physical seals would retain air to some degree. Electrolysis of water to produce oxygen was part of the solution, done with the knowledge that on an industrial scale it would accelerate the disappearance of the oceans. The longer term plan was to build an atmosphere plant (which would not only provide breathable air but adjust its composition to ensure a proper balance of greenhouse and non-greenhouse gases) and canals; however these would not be ready in time to prevent significant ecological collapse. The black race began to specialize in bio-engineering (Weird Science Alert!). They realized that life would get tougher and that the current short lifespan and live birth would not be optimum in a tough environment. They also realized that the relatively short life span limited the effectiveness of the individual in defining and making the changes necessary for survival. Research into life extension and conversion to egg-laying began. Eggs would better protect the growing child from a harsh environment, eliminate the vulnerability of the mother during pregnancy, and allow storage and selective birth. They introduced these changes into themselves first, and thus are the "First Born" of the Barsoomian races from eggs, lending some truth to their name for themselves. The yellow race began to specialize in the physical sciences, and also exploring the arctic regions in secret. They created plastics and refined the uses of radium into a science. They secretly established some small domed settlements in the arctic, and also developed the radium lighting found in some dead cities.
There was much debate on city pits vs. rift valleys and caverns as safeholds. The pits would be better at retaining air because they could be more easily sealed, but where food would come from was unclear. The mentalists13 sought to create food via the power of thought alone. Experiments with using radium lights for growing crops were successful but of insufficient scale to support a large population indefinitely. The pits were thus viewed as a shorter term solution – they also had small scale air pumps (air compression – the air was there just not enough). Experiments with solar and gravity power for the pumps were also conducted.
Biological engineering would have accelerated, with many successes. More practical genetic engineering means were found to extend life to about 1000 years, and to also reduce the need for water and transition to human egg-laying. Other animal forms were also similarly engineered for egg-laying. Eggs also began to be stored. The story of the Tree of Life derives from legends of this time. Other forms, such as the dead sea bottom moss, would also have been developed.
Although these changes were introduced into the white, black, and yellow races this was viewed as only a partial solution. The optimum solution was to engineer the red race from all three existing races – an even tougher and better tailored human for the new environment that was coming (hybrids already existed). Other plant and animal species were also similarly toughened with the goal of creating a new ecology suited to the tough environmental conditions coming, or to at least meet this change "in the middle."
This accelerated industrialization was a resource drain, and caused further reduction in available resources (and possibly further climate change). Martial law might have been declared if panic ensued. Constraints on travel arose as ships were commandeered for project support, or were lost and could not be replaced due to the shortage of wood. Some pirate attacks on ships and cities might occur as resources began to be scarce. Withdrawal to larger cities to pool resources might have occurred, with abandoning of smaller settlements. Green men extermination expeditions would have ended. We would see the beginning of reduction of birth rate.
5. 750,000 years ago.
Barsoom is now a very different place due to accelerating climatological change from both natural and man-made processes. The Okar and particularly the First Born begin to become isolated from each other and the other races. Commerce and civilization in the Southern hemisphere essentially ends except where the rising populations of the red men permit them to move into cities abandoned by the other races where resource availability, geography, and the availability of safeholds permit. The deeper oceans of the Northern hemisphere, although much reduced, allow civilization to persist there a bit longer. Caravans begin to replace maritime commerce, but cannot sustain the volume of shipping and become a target for marauders and the increasing hordes of green men.
The birth rate continues to plummet, which further accelerates the abandonment of cities. We begin to see some adaptation to lower air pressure. The cities that remain populated experience significant breakdowns of society and social services. The technological and industrial base developed 150,000 years prior is eroding, although the scattered safeholds retain some of it.
Life has gotten ugly. The Southern plains became uninhabitable except for green men and the safeholds of the First Born. Life is better in the North, and Orovar civilization is still very much in evidence.The short term survival plans are in place, with migration to new niches and safeholds. There is a rise of warlords who take over some of the safeholds – some are benevolent and some not. Some wars and riots for safeholds occur as there is still more population than could fit in them – some safeholds are destroyed as result, or seized by the green men who enslave their occupants. Suspicion of strangers begins as they could be advance scouts for raiding parties. This also results in the rise of the warrior, with universal arming of the populace and the beginnings of a far more martial culture. Extreme protection of females begins. Some cannibalism occurs in areas of complete ecological collapse. There is much storing of eggs in the safeholds.
Despite all this we have the beginnings of the great canal systems, begun largely by Okarian engineers who build safeholds within the extensive network of old lava tubes within the Tharsis Montes. These early canals, along with some rivers and other water courses that might have been artificially connected and deepened, were the beginnings of the vast canal network. These canals would allow repopulation of some areas that had been abandoned.
5. 500,000 years ago
Civilization and maritime commerce is gone – the classical civilizations have effectively ended and been replaced by a network of safeholds that follow the expanding network of canals. The oceans are mostly gone as a medium for transportation (ships had to moor too far from most cities) except in the far North. Ecological collapse accelerates. There is loss of some of the more marginal safeholds due to failure of life support or to disease. Any remaining enclaves of non-egg-layers die out, with discontinuities in family lines. Remaining enclaves of First Born or Okar not at their polar safeholds begin to die-out or interbreed early on. There is complete loss of communications between the races. The atmosphere plant, designed by the Okar but built by the Orovars and finished by the red men is partially operational but not before additional population loss occurs. Life is now limited to the safeholds and moisture traps.
6. 250,000 to 100,000 years ago.
The oceans are gone for all practical purposes.Canal building continues as the dried out Northern seabeds permitted land access to the polar ice and the north polar continent. The atmosphere plant is now fully operational which stabilizes the drying and atmosphere loss – a new equilibrium of atmosphere and water retention is reached. Population begins to slowly increase again, but civilization is still a remembered dream. Many leave the more isolated safeholds, which by now are almost entirely populated by red men – the Orovars are mostly gone as a pure-bred race with the exception of a few northern enclaves. The Okar have mostly retreated to their domed North Polar cities while the First Born have retreated to the Valleys Dor and Kamtol. Some abandoned cities are repopulated, and some new cities are built in especially hospitable areas. Green men take over some deserted cities.
We now see “modern” Barsoom. The red men dominate, with the Okar and the First Born restricted to their polar refuges.
1 Lothar in Thuvia, Maid of Mars; The Citadel of Horz in Llana of Gathol
2 Cf. Pirates at Xanator, Voyage to Zodanga
3 Many excellent works are available on ERBzine by such as Den Valdron and Rick Johnson.
4 Chessmen of Mars
5 Cf. A New Map Of Barsoom, Geographers Of Mars I: Matching Mars And Barsoom, Mapping Barsoom II, Mapping Barsoom II, Mapping Barsoom III
6 Cf. Master of Adventure: The Worlds of Edgar Rice Burroughs, by Richard A. Lupoff. However, we must remember that science fiction is often based on the author's world view, and what ERB writes is plausible in that light.
7 In other words, exceeding the escape velocity of the planet in question.
8 Evolution on Barsoom
9 I’m intentionally ignoring the three—legged ulsios of John Carter and the Giant of Mars.
10 ERB never tells us how thoats, calots, etc. breed. Are they egg-layers?
11 They certainly co-existed with the black and yellow races. What was the nature of their interactions? There might be a story or two here also. Were the red hybrids already emerging?
12 Akin to "generation ships" from other sci-fi genres
13 See Thuvia Maid of Mars