The old Amazon

By Razib Khan | January 14, 2012 2:49 pm

Once Hidden by Forest, Carvings in Land Attest to Amazon’s Lost World:

For some scholars of human history in Amazonia, the geoglyphs in the Brazilian state of Acre and other archaeological sites suggest that the forests of the western Amazon, previously considered uninhabitable for sophisticated societies partly because of the quality of their soils, may not have been as “Edenic” as some environmentalists contend.

Instead of being pristine forests, barely inhabited by people, parts of the Amazon may have been home for centuries to large populations numbering well into the thousands and living in dozens of towns connected by road networks, explains the American writer Charles C. Mann. In fact, according to Mr. Mann, the British explorer Percy Fawcett vanished on his 1925 quest to find the lost “City of Z” in the Xingu, one area with such urban settlements.

In addition to parts of the Amazon being “much more thickly populated than previously thought,” Mr. Mann, the author of “1491,” a groundbreaking book about the Americas before the arrival of Columbus, said, “these people purposefully modified their environment in long-lasting ways.”

If one wants to recreate pre-Columbian Amazonia, most of the forest needs to be removed, with many people and a managed, highly productive landscape replacing it,” said William Woods, a geographer at the University of Kansas who is part of a team studying the Acre geoglyphs.

“I know that this will not sit well with ardent environmentalists,” Mr. Woods said, “but what else can one say?”

There are two descriptive models which have to be interpreted in different normative frames. First, there is the model whereby before the arrival of the Europeans the New World was lightly populated by indigenous groups which had a minimal impact upon the environment. This is the description. Before the 1960s this was viewed by the mainstream culture as a rationale for the justified conquest of the New World by Europeans, who put the land to productive economic usage, whereas before it had been fallow and under-untilized. After the 1960s many, especially in the environmental movement, inverted the moral valence of the description. Instead of being primitive savages, the native peoples were at balance with the environment. Rather than an outmoded way of life to be superseded, they were a potential model for the future.

The second descriptive model is the one that Charles C. Mann outlines in 1491: New Revelations of the Americas Before Columbus. It posits that in fact the New World was much more heavily populated and its environment more impacted by humanity than we had thought previously. Rather, it suggests that the introduction of Old World diseases resulted in massive population crashes, subsequent to which there was a “re-wilding” of much of the Americas. Mann focuses more on the period before the arrival of Europeans, but if you read the scholarship on the arrival of Paleo-Indians there is a fair amount of evidence that even their appearance resulted in a massive change in the suite of fauna which characterized the New World (e.g., the gray wolf and American bison are also Holocene newcomers, just like man).

Some have argued tat Mann has taken a maximalist position (in fact, some readers have lied and stated that Mann argued that the Amazon was as populated as Bangladesh!). But even granting that Mann may be sampling from the more revisionist tail of the scholarship, I think it is creditable that we need to move away from the extreme position of the first descriptive model. There is a fair amount of circumstantial evidence that New World civilizations had not attained the same level of sophistication and complexity as Old World civilizations (see Guns, Germs, and Steel for some of the reasons why). But it is also likely that the Aztecs and Incas were not sui generis aberrations, but rather one point along the spectrum of social complexity which characterized the New World.

This is a subtle point though, because the new model also has normative ramifications. I state above that New World civilizations were not as complex or developed as Old World ones, and that is not a position that many are comfortable with. Rather, they may want to assert that the New World societies were just as complex and sophisticated as the Old World civilizations, that fundamentally all civilizations have equal value and similar character. Therefore, these partisans are particularly enthusiastic about the model which Charles C. Mann popularizes in 1491, as it reverses the narrative of noble simple savages, projecting the indigenous as highly cultured, and only brought down by the biological weapons which Europeans brought.

Where does that put those who wish to construct a plausible model of reality, rather than a mythic history for purposes of ideology? It is lazy to simply pick the position in the middle, but in this case that’s probably the most prudent unless you want to dive into the primary literature yourself. I don’t accept the old model anymore for a variety of reasons, not just having to do with the natural history of the New World. But, I can’t personally assess in detail the magnitude of the numbers that some of the scholars Mann relies upon to revise upward population estimates. So I take the revision with a grain of salt and some caution.

I would conclude that there is one reason I can think of why the Amazon basin might have been more suitable for human habitation that some other wet tropical zones in the Old World: the relative lack of disease. Many wet lowland zones which would otherwise be suitable farmland are lightly populated due to malaria, but this was not an issue in the New World before 1492.

CATEGORIZED UNDER: Agriculture, Anthroplogy, Environment
MORE ABOUT: Amazon, Charles C. Mann

Comments (4)

  1. dave chamberlin

    I think Charles Mann’s book 1491 is revolutionary book, much like Jared Diamonds “Guns Germs and Steel” was for it’s day. I hope that each of these books continue to inspire research so that a more complex picture emerges of their respective subject areas. If in time these books become outdated or over simplified, I hope these books continue to be given the respect they deserve for the new broader perspectives they have helped create.

  2. Scott

    “‘If one wants to recreate pre-Columbian Amazonia, most of the forest needs to be removed, with many people and a managed, highly productive landscape replacing it,’ said William Woods, a geographer at the University of Kansas who is part of a team studying the Acre geoglyphs.”

    Does anyone actually believe this crap? I buy into Charles Mann’s hypothesis more than Razib, probably. I’m sure that population numbers in pre-Columbian Amazonia were much higher than previously thought and that the cultures were much more sophisticated.

    But I don’t know how anyone could believe that MOST of the Amazonian forest was REMOVED during the pre-Columbian era. In order for that to happen, populations would have to be on the level they are now (ie, several humdred million).

    This was clearly spoken by someone with a political axe to grind.

  3. #2, seemed too strong to me too.

  4. Query if the arid period that wiped out civilizations in the American Southwest around 1000 CE might have made civilization possible in what would otherwise have been too dense a jungle in the Amazon?

    The geographic scale of the South American Tupi and Macro-Je-Kaingang language families of that region are suggestive of the possibility that there might have been a couple of large scale Amazonian civilizations at a time depth shallow enough to leave a linguistic trace.

    A 2008 National Geographic story linked in the story quoted above, suggests that a contemporaneous neighboring civilization had, at “their height between A.D. 1250 and 1650, the clusters may have housed around 50,000 people” with individual subcities in a cluster each built on perhaps 150 acres.

    A few comparisons can ground that number:

    Roman era London had about 60,000. The Sumerian City of Uruk probably reached about that size on the late end of the time range from ca. 4100 BCE to 2900 BCE. Jericho had a population of less than 3,000 in the pre-pottery Neolithic A (through about 7300 BCE), and probably didn’t have 50,000 people until sometime in the early copper or bronze ages. At its peak, pre-Columbian Mexico City probably had 150,000 people, and perhaps a dozen other cities in the Aztec sphere of influence had more than 10,000.

    The Inca empire on the eve of the arrival of Columbus is estimated to have had 12 million people, although the estimates are necessarily rough and the population density of 39 per square mile would have included large expanses of low population density villages and hamlets interspersed with more dense cities. It isn’t really clear how populous the largest urban areas there would have been.

    Ancient Rome had from 450,000 to a couple of million people in its peak years and had fallen to under 50,000 around 500 CE, after its fall. Athens had perhaps 250,000 people in its 5th century BCE Golden era of the ancient world. Homeric Troy was probably smaller than Athens but still of the same order of magnitude, and pre-Epic Troy of the Bronze Age may have been around 50,000 people.

    In sum, these Amazonian civilizations were operating on a copper age/early Bronze Age scale, but their largest cities were probably smaller than the largest Inca or Aztec cities.


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About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at


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