This is a great cartoon by Randall Munroe that makes a very important point very effectively. Spread it around, love it, learn from it.

Here is an excellent video walkthrough of the cartoon, discussing its value as a communication tool.

But do ignore the details of the prehistory because the cartoonist has fallen into the same trap so many others have, well meaning in intention but simply a) not an expert on key things and b) unaware of the real consequences of getting certain things wrong.

When we represent prehistory, we represent humanity both past and present. It is not difficult to do so in a way that leads to serious and meaningful, even impactful, misconceptions.

So, here, I’m going to complain not just about this cartoon, but about the general phenomenon of people who are not paleontologists or archaeologists (or some other appropriate expert) using human prehistory to make a point, but at the same time, throwing accuracy about that prehistory under the bus.

Right way, I want to point out the consequences: Westerners, for sure, but this is more widespread than that, tend to have a view of humans that involve concepts of civilized and primitive, and hierarchical concepts mixed with evolutionary ones. And there are other problems in the conceptualization of prehistory and the diversity of humanity. These problems make it very easy to maintain a racist perspective despite overwhelming evidence against the validity of biological race. These problems make it very easy to lessen the pain and suffering of certain people, which, often, we are busy causing in our own self interest. These problems in conceptualizing the nature of humanity across time and space lead to all sorts of misunderstandings with all sort of consequences including, but not limited to, simply getting it all wrong.

XKCD is a comic written in and fully appreciated by the context of modern skepticism and science cheerleading. Let us please not throw the important social and natural sciences of archaeology, prehistory, paleoanthropology, etc. under the bus in service of making a point in some other area of study. A smart man whom I respect quipped, “but this comic is not about archaeology.” My answer to that: This comic makes one point about climate change and dozens of points about archaeology. It is about archaeology.

Why this is a great cartoon.

Look at the cartoon. Go from top to bottom.

It tells us that over a very long period of time, as humans did all sorts of different things, and conditions on the earth changed dramatically, the global surface temperature a) remained within a fairly narrow range and b) didn’t vary that quickly even when it did vary.

Then, all of the sudden, temperatures shoot way up and are expected to shoot way up even more. Holy crap. Point well made.

Missed opportunities

The climate change science is not bad but a bit off. The baseline of temperatures (pre industrial) vs. now should be somewhat different in relation to the current temperature. If you take the last few thousand years as basline, which is the proper thing to do, we are closer to 1.5, and not 1.0, degrees C above it. But that may be a nitpick since the time scale of this cartoon is larger. But, once you get past that level of time scale, the question of baseline becomes untethered from pragmatics and you can justify anything.

Also, there are probably times in the past, within the time range of this cartoon, where more abrupt and dramatic climate change did indeed occur. And, at those times, major effects happens with humans.

This is where not getting the archaeology right causes the cartoon to both miss some key points and become inadvertantly somewhat less than straight forward.

Here’s the thing. Climate change can have a very negative effect on humans. How do we know? Because it apparently has happened over and over again. For example (and there are many examples), within the time range of this graphic, climate changed caused a significant increase in aridity in a huge area of southern Africa. The place was pretty well populated by hunter-gatherers before that, and after that, and for thousands of years, no one could live there. Climate change had made the region uninhabitable for humans.

Similarly, climate change probably caused depopulations, evacuations, and migrations in many other parts of the world at several points in time represented here.

Critics from the denier side of things would point out that climate change has always caused problems, so this new change is no big deal, and XKCD ignore this. But the cartoon, had it mentioned more of these earlier changes, would instead represent a different fact: Natural variation in climate can be catastrophic to humans. The level of change happening now, and expected in the near future, still caused by humans, is much larger than what happened during this time period, or faster. So look out!!!

But that’s not the point I want to make.

Simple facts and big concepts

NOTE: Since I wrote this post, at least one change was made in the original carton, pertaining to the flooding of the scablands in Washington State. Perhaps other changes will be made over time!

There are a number of simple facts that the time line either gets wrong or represents in a way that we would not like for a basic intro class in archaeology or paleontology. Some of these facts were pointed out to me by John McKay or Helga Ingeborg Vierich. This is not comprehensive, but gets the point across:

  • Impressive prehsitoric art appears on the cartoon at 15K. Art and adornmnent appear well before the time line begins, and jot just in Europe. The super impressive cave wall art dates well before the time line, and somewhat less impressive works occur very much earlier. This is a decades old conception overturned many years ago.
  • The Clovis First model of the peopling of the Americas is on its last legs and should not be used as assumed knowledge.
  • The Missoula mega-flods affected eastern Washington, not Oregon.
  • The glaciers weren’t just in New York and Boston, they covered many other places. If the idea is to connect glacial geography to people’s lives, references to other areas might be helpful.
  • Wrangle Island is not tiny. He may have confused Wrangle Island with Ts. Paul in the Privilovs.
  • Abu Hureyra is one of several sites with early year round settlement. More important may be the more southerly Natufian, where foraging peoples, for a very long time, took up permanent settlement, and the first commensal organisms (which would become very important to humans, like plague carrying rats and domestic dogs, etc.) came on the scene.
  • Agriculture has multiple origins, but a single origin is implied here.
  • The origin of copper metal working happens in multiple places (two with smelting in the old world, plus it was worked in the new world).
  • Similarly, other metal working has multiple origins.
  • People will fight about the date for “proto-indo-european” languages or even is fuch a proto-thing existed or could be dates. The majority of historical linguists don’t accept this at all. But if that is right or not, again, Indo-European languages are not particularly important in overall human history. The cartoon centralizes a relatively rare language group and ignores thousands of other language groups, as though the mostly post hoc Western lineage of human civilization is assumed to be the most important.
  • “Permanent settlement in the fertile crescent” is out of the blue, and contradicted earlier on the time line. Permanent settlements in the region predate this by 6,000 years.
  • All of the early steps in civilization rising are focused on a very limited area, represent only a small (and very Western oriented) portion of civilization, ignoring most of human prehistory, and privilege “civilization” over what the fast majority of people were doing at the time.
  • Same problem with writing. Writing was invented many times over many areas, but it looks here like it may have a single origin, the origin that is part of the Western Civilization story.
  • Missed opportunity: “Invasion of the sea peoples” may very well have been an example of climate change messing up a population and causing a mass migration.
  • For later civilizations, I appreciate the reference to the New World. But again, it is only part of the story, mentioning a small part of the record. Isn’t it a much more interesting story to note that between 10K and 2K (or so) dozens of independent highly organized hierarchical societies, often referred to as “this or that civilization” arose all over the world, while at the same time, the vast majority of people lived off the land as foragers?
  • The Industrial Revolution starts in the 18th, not 19th,century, in Europe.

Larger scale things you might learn from this graphic that are wrong.

That agriculture was invented once, as part of Western Civilization, and the same for metal working, marginalizes the new world, many regions of Asia, many regions of Africa. These are misconceptions that those of us who teach intro to world prehistory or similar courses have to spend a large amount of our time refuting.

The idea seems to be represented that humans made the transition from hunter-gatherers at one point in time and thereafter were mostly agriculturalists. The opposite is true. Most humans were living in small groups as hunter gatherers for the entire time represented by this cartoon, except at the end. Half the humans or more at the time of Christ, for example. It is likely that in many regions, at various points in time, an early stab at horticulture was abandoned, and people returned to agriculture.

Is this important?

Well, getting facts right is important. In the case of prehistory, this mainly means not overstating the facts. One might argue that in a simplified version of reality (like in a cartoon) it is ok to overstate things as facts where we really don’t know. No, it isn’t. There are ways to speak briefly, and in an interesting way, of a past that we understand more vaguely than some DK book for five year olds. So let’s do that.

The oversimplification of prehistory contributes to the co-opting of intelligence, innovation, rights over various things like landscapes and cultural phenomena, by the dominant cultures who have condensed the relevant prehistories to centralize and privilege themselves. The prehistory presented here mostly privilages what we sometimes refer to as “Western Civilization” with its middle eastern roots and its simple, linear, one way, always improving, progressive history. A very inaccurate history.

As Helga Vierlich wrote on my Facebook timeline, “In short, this reflects a preoccupation with “progress” whereas what it really shows is a progressive ecosystem and social clusterfuck that brings us to the present situation – characterized by continuing destruction of the last ecologically sustainable (“indigenous”) economies… and also characterized by deforestation, massive climate change, pollution, ecosystem distraction, soil erosion, and species extinction.”

So, in making a point about self destruction by the human species, due to anthropogenic climate change, the oversimplification misses key points in that actual process.

But it is still a good cartoon.

I would like people who pass this cartoon around to make a brief statement, like, “I hear the prehistory is oversimplified a bit, but this makes a great point about climate change” or words to that effect. Many will argue that this statement is not enough. But I’m not a big fan of sacrificing the really cool for the sake of the perfectly pedantical. Usually.


  1. #1 Ellen
    United States
    September 13, 2016

    So, I guess my undergrad foundation in archaeology, combined with 25+ years of following the latest findings in the popular press still holds up! I, too, found the prehistory parts kinda cringe-worthy, especially the cave paintings and the earliest peopling of NA. I had not given much thought to the way erroneous info created a Western linear narrative, so thank you for the insight.

  2. #2 Iain Davidson
    September 13, 2016

    The detail that I think they overlook is that there was a massive and very rapid climatic shift, warmer, colder then warmer again, in much of the northern hemisphere, less so down here, in the part they call the Younger Dryas. And this was not insignificant. In Europe it marked the end of the culture that produced cave art. In the middle east it is said to be part of the reason agriculture happened. So those are pretty big impacts on humans of climate changes. It would be good to have the scale of those changes on the same scale as the modern climate change. The big difference is that with past climatic changes on big scales, population levels were low and people could move around relatively easily or find new resources to keep them alive (provided they could get water). But assuming similar human responses, to say nothing of animal and plant responses, to the warming currently going on, there is very much less that we can do because there are so many people everywhere. Ultimately, stopping the boats may be a solution for us, but there will still be a problem everywhere else (as we see).
    You can find the relevant references about the Younger Dryas and my comment on them at

  3. […] (9/13/16): This is interesting. Over at, Greg Laden points out that many of the historic markers in the graphic fall into the trap of […]

  4. #4 Susan Anderson
    September 13, 2016

    Thanks VERY much! This is useful. I’ve been reading an occasionally cringeworthy but thought provoking (oddly contradictory to its point; people making a good and imho glib academic living dissing human activity) book, Anthropocene or Capitalocene, which covers some of the issues you mention. It introduced me to the concept of “cheap nature” and cheap labor, tracing the seed of human self-destruction to our habit of not restoring but rather expanding what we take. The history of deforestation starting with Columbus is particularly appalling. We cannot stop exploiting until we know we are doing it.

    It seems the “manifest destiny” of human and particularly US Americans is something we will not lightly let go, perhaps to the final dirty endgame of collapse.

  5. #5 Michael Tobis
    September 13, 2016

    I don’t get it.

    If you had to choose color text to uniquely identify each time period in the Holocene with some human-relevant events, wouldn’t they be about the introduction of new technologies?

    You don’t think the domestication of the dog or the horse is a big deal because they are part of an ethnocentric narrative?

    I just don’t get it.

    Before you try to explain it to me again, I’d challenge you to propose some alternative human events that would satisfy the needs of the cartoon and also pass your test.

  6. #6 Greg Laden
    September 13, 2016


    I could easily suggest a set of touchstones to use in a cartoon like this, which would provide historical time-embedded reference points, be interesting, probably something interesting to draw a stick figure for, and not be problematic in the ways suggested here.

    For example, we could have four or five technologies, we could have a half dozen or so “origin” events for horticulture or animal husbandry, we could have one or two migration points, and seven or eight separate “civilizations” Like he has now. But, instead of having most of them on the same traditional V. Gordon Childe style Western Civilization timeline, only some of them would be on that timeline. They would be distributed across the world evenly, so everyone could have part of the history, and we would not be privileging, yet again, Western Civilization As Central To All Things narrative. This is not hard.

    That’s the first and probably main thing I’d change.

    Then, I’d add something in there, about 3K y.o or so, that said something like “60% or so of humans live in diverse foraging or mixed economy societies” just to emphasize that when we refer to ag/hort/pastoralism and civilization we are still talking about a minority of people.

    I wouldn’t bother with the historic reversals. The cartoon is, after all, not about the nuances of the past. But the above are NOT nuances. They are primary concepts.

    The third thing I would do, as noted, but this changes and complexities the climate narrative a bit, is to note where climate change did impact humans here and there in a big way (much would have to be speculative, but it can be described as such) even though the climate shifts were presumably small compared to the present day and immediate future.

  7. #7 riverat
    Willamette Valley, Oregon
    September 14, 2016

    One nitpick. The Missoula floods did affect Oregon significantly although certainly not to the extent of the scab lands of Eastern Washington. In passing down the Columbia River they were deep enough at Portland to flood the Willamette Valley as far south as Harrisburg, about 80 miles south of Portland and at 310 feet in elevation. Erratics floated in on ice bergs were found around Harrisburg. I’ve heard that much of the good soil in the valley came from the soil scoured off of the scab lands and washed in.

  8. #8 Greg Laden
    September 14, 2016

    Riverat, yes. Also, the floods are placed on the cartoon about 500 years later than they happened, I think, and they occurred many times over a 2K or so period of time.

  9. #9 John J. McKay
    United States
    September 14, 2016

    There were about 40 floods over a 2000 year period. His marker is a few hundred years in.

  10. #10 Kevin
    United States
    September 14, 2016

    Legit criticism, but while accuracy and non-western-centric perspectives are important, the cartoonist was writing to give his audience familiar historical touchstones so that they could conceptualize the ultimate point about the modern rate of climate change. He included events that the lay audience would be familiar with, and it seems a little odd to complain that his climate cartoon failed to also be a great archaeology cartoon. Yes, it’s a biased cartoon and I hope that he does other, more accurate ones on human history in the future, but he accomplished his goal.

    And he accomplished it better than the entire climate science community has managed to do over decades of failed communication.

  11. #11 Greg Laden
    September 14, 2016

    Kevin, the lay audience includes a lot of people with South American, Asian, and African heritage, for example, who are familiar with their history to know that there were civilizations of various sorts, innovations of various sorts, in that time. But not for them in this cartoon!

    It is possible that Monroe only writes for a European ethnic audience mainly in the US but I doubt it (the mainly in the US part might be right, but the US is not that monolithic culturally).

    Let me be clear: I am not complaining that it is not a great archaeology cartoon If that was the problem this wouldn’t be a thing. It is not an archaeology cartoon. As a colleague who did not like my critique said, “people are not even going to notice the problems with the archaeology”… and that is exactly the point. They won’t notice it, they will just absorb it, and the various and often destructive myths will be reified, reinforced, strengthened, continued, and made legit by a modern depiction in case anyone was wondering if anything changed since they were taught all this stuff badly in social studies class years ago!

    The cartoon does accomplish something important, and I say that at the beginning and end of the post.

    You should know that among climate scientists there are critiques of his handling of earlier variation in surface temperatures, by the way.

    But, in any event, this cartoon does what Mann and Hughes did years ago, and quite a few graphics have come out doing just what Monroe does here. This cartoon may be the best of the lot, or maybe not, but it is not correct or fair to others to say that every other effort has been failed communication. You probably just haven’t seen other stuff.

    So, it might be better. Or not quite better but in the top 5%. It is flawed wrt the archaeology, in important ways, and fixable. It may or may not be a great representation of earlier surface temperature change. Holocene variation is something I’m quite familiar with and I would never have depicted the Holocene as a nearly flat line. That is more an effect of moving average (sort of) than actual lack of change. There are very some abrupt changes in the late Pleistocene glossed here.

    He misses opportunities; the graphic seems to show zero effect on humans from climate until now, and this is demonstrably wrong. One could come away form this cartoon with the conclusion that he’s glossing ancient and natural variation or that such variation existed but, lo and behold, look at the archaeology, we’ve never been knocked off the time line by that, so why should we now? And the biggest change on the graph is the future, predicted, by models and who trusts models? And so on and so forth. This cartoon is just as subject to a Gish Gallop approach as anything that anyone else has ever done.

    No, this is not an unflawed attempt at communication. It is very cool. But it has the same problems every other attempt has, and I can tell you exactly what those problems arise from (though I suspect you already know):

    We are engaged in a dishonest conversation. If this was an honest conversation, this graph (with the archaeology fixed, of course) would make a great point and be wonderful. But since this is a dishonest conversation (between the deniers and the scientists, with the deniers forcing the dishonesty, to be clear) this graphic and every other attempt has plenty of handles for anyone who wants to grab something bad out of it.

  12. #12 Kevin
    September 14, 2016

    Thanks for the response; your points are well taken. I’m hoping this Monroe’s effort here can be the seed of something that continually grows and is revised and stays visible in popular culture.

  13. #13 BBD
    September 15, 2016


    He misses opportunities; the graphic seems to show zero effect on humans from climate until now, and this is demonstrably wrong.

    Are you referring to the Ruddiman hypothesis here?

  14. #14 Greg Laden
    September 15, 2016

    Not really, I was thinking simply of the increasing evidence that under conditions at the more extreme end of natural climate variability human populations have been vulnerable. Given that, we should assume that our species is generally somewhat vulnerable to climate change.

    This seems almost stupid to bother with, who would think otherwise? But people do think otherwise, or at least, make the claim.

  15. #15 MikeL
    September 15, 2016

    I hear what you’re saying (I notice all the nitpicks now that you point them out), but it strikes me that the cartoon does actual prehistory educators a service by collecting all the misconceptions in one place, so a lecturer can spend a lesson discussing the western-centric reductive narrative presented in the comic.

    I could see Munroe doing a followup where he depicts the vagaries of the non-linear progression of prehistory (he’s been more than willing to dive into such things previously), but for this I’d argue that the point he makes about climate change neccessitated a strong, uncomplicated narrative of prehistory – and I’m actually surprised he didn’t simplify it down further.

  16. #16 Greg Laden
    September 15, 2016

    MikeL Exactly. I am an educator in the area of prehistory. I came across this cartoon. I do a certain amount of my edumication duties on this blog. And, so … !!!

    I agree that the narrative of time needs to e uncomplicated and strong, and contain things people relate to. This can be done, easily, while a) getting the details right and b) not reifying the heternomrativewesternopatriarchy.

    I would object that these are not nitpics. This is important stuff. Among the suggested issues one could rank them on a nitpic to serious points off if it was on an exam scale, and the most nitpicky thing would be how many floods happened in the scablands and when they happened, which probably doesn’t matter at all because the point is made, just a bit off.

  17. #17 Mark Draughn
    September 15, 2016

    So, for those of us who are curious about all things science, do you have any recommendations about how to start getting the prehistory picture right? Perhaps a good website to start at, or a textbook that isn’t deadly dry? A popular book, maybe?

  18. […] ways of communicating the risks posed of rapid warming, which brings us back to the great (but not perfect) xkcd cartoon. Here it is in […]

  19. #19 Greg Laden
    September 15, 2016

    Mark, there has never been a great overview of prehistory for the general public that wasn’t problematic in some way or another.

    Diamond’s books that look at the distant past do a good job of getting mostly out of the mold, but they are heavily criticized for being off at least a little on every fact, off a lot by some.

    Modern day World Prehistory classes taught by good teachers are good. The line I’m giving you here in this post is the same that is currently normally given in modern day up to date classes.

    I use The Human Past: World Prehistory and the Development of Human Societies (Third Edition) as a textbook in those cases. I’m not sure it is the best but I like it a lot.Each area is covered by a different set of experts, so they’ll show some bias in how great their own area/time period is, but if you spread that across time and space the you are there.

  20. #20 CherryBombSim
    September 15, 2016

    Can I whinge about the geology, too?

    “Ice sheets around Alaska shrink, exposing a land bridge between Asia and North America.”

    Beringia was never glaciated, people could just stroll across at the LGM.

  21. #21 StevoR
    Adelaide hills, South Australia
    September 15, 2016

    Excellent analysis and corrections to a graphic graphic here. Thankyou Greg Laden, I’ve learnt from this.

    FWIW. I’m one of those who have enjoyed and shared this widely online originally – and thought at the time it was fascinating and completely factually accurate.

  22. #22 WesP
    September 15, 2016


    >People will fight about the date for “proto-indo-european” languages or even is fuch a proto-thing existed or could be dates. The majority of historical linguists don’t accept this at all.

    Can you clarify this point?

  23. #23 BBD
    September 16, 2016

    Mark Draughn

    So, for those of us who are curious about all things science, do you have any recommendations about how to start getting the prehistory picture right? Perhaps a good website to start at, or a textbook that isn’t deadly dry? A popular book, maybe?

    I rather liked Steven MIthen’s After the Ice: A Global Human History, 20,000 – 5,000BC. It’s been some years since I read it, but IIRC it was in reasonable accord with what Greg says above and in the OP. And it’s readable, though a bit of a doorstop. But…

    Mark, there has never been a great overview of prehistory for the general public that wasn’t problematic in some way or another.


    … So I could well be unaware of all sorts of issues.

  24. #24 Susan Anderson
    September 16, 2016

    My Capitalocene book is too annoying to seriously recommend, though there’s some good stuff in it. But it does cover in detail the plundering of empire, Spanish, Portuguese, British (and no doubt Dutch) associated with world travel, resulting in deforestation and piles of toxic rubble (and disease and slavery) everywhere they went. From this you might intuit my objection: it’s all too extreme.

    I mean: here we all are and what are we going to do about it? Yes, we’ve been bad, but not entirely so. And our existence is not a matter for debate.