Response to Comment

 

A Sophist wrote a comment in response to the blog entry Diamond attempts to defend myths of Easter Island: Lipo and Hunt respond :

My questions remain: 1. Were there Palm trees on Easter Island when the first Europeans visited? And if not, then H+L are arguing this was rats and not humans cutting the trees down? 2. If Palm Trees are unable to be made into canoes, how did the people make ocean going canoes? In there were no canoes, how did Dolphin get into the diet? I guess I am missing the problem. This seems to be a lesson in how isolated political leaders who do not feel the pain of their actions (cutting down the forest for whatever bloody reason: fuel, canoes, to move statues, etc) can lead their society to the brink of destruction. 

The questions themselves point to common but false assumptions often made about Easter Island prehistory and they are worthing examining. 

Question #1:  Palm Trees.  I’m not sure how the two different parts to the question are related (i.e., whether there were palm trees at contact in 1722 and whether rats “cut down” the trees). For the first question: no one knows exactly whether there living examples of palm trees on the island in AD 1722 when Roggeveen first arrived nor later in the 1770s when the Spanish and English arrived.  The overall impression we get from these early written accounts is that the island was largely devoid of trees though there are also mentions of “palms” in some of the descriptions.  The pollen and macro  botanical record is equally unclear given the relatively poor dating of the island as a whole and relatively few dates of palm nuts in particular. A major effort to date events on the island (with modern understanding of the need to link past events with dated events) would go a long way to resolve this issue (among many others). 

One difficulty in resolving pre- versus post- contact differences in the island’s landscape and ecology is the fact that point at which researchers arrived on the island to make systematic descriptions is more than 250 years after initial contact and decades after the island was turned into a sheep ranch. Certainly, the presence of 60,000 sheep and associated ranching activities likely resulted in the final termination of many plants that may have been present in small numbers in late prehistory.  So the timing of the final termination of the palm is still a bit unclear.

The second part of the question seems to assume that we (Hunt and Lipo) argued that it was “rats… cutting the trees down.” The statement is absurd to begin with and of course we have never argued this. What we have argued is that arrival of rats with humans on to the island brought immediate and substantial changes to the ecology of the island. The introduction of rats is really the introduction of the first teeth on the island and their presence (as is well documented in many environments) will impact native vegetation especially that which has coevolved dispersal mechanisms with birds. The impact of rat is a fact and indisputable given the evidence that exists of rat gnawing seeds. But did they “cause” the trees to go extinct (as this question implies we say)?

The answer is, of course, no. The rats did not cause the palm forest to go extinct for several reasons. First, things don’t “cause” other things to happen except in common sense (see Sellars 1963: Science, perception and reality).  Second, while rat predation on palm nuts has been an ignored factor in the vegetation changes that are commensurate with human arrivals, rats were not the sole factor.  We *do* know that rat predation on seeds can make massive changes in vegetation and even extinction even when humans are not present.  As Hunt has discussed, the elimination of Pritchardia palm in the Ewa Plain clearly predates the actual arrival of humans (see Hunt, T., 2007. Journal of Archaeological Science 34 (2007) 485-502; Athens, J.S., Tuggle, H.D., Ward, J.V., Welch, D.J., 2002. Avifaunal extinc- tions, vegetation change, and Polynesian impacts in prehistoric Hawai’i. Archaeology in Oceania 37, 57-78.p. 73).

On Easter Island with its tiny size (about 6x10miles), however, there was never a point at which rats were separate from humans. It takes about an afternoon to walk from one side of Rapa Nui to the other: human and rat impacts will be effectively simultaneous across the the entire island.  We know that the people arriving on Easter Island were slash-and-burn cultivationists — a strategy we side widespread across the Pacific (and indeed around the world). Their lives depended on transforming the environment to one that was capable of supporting human life through the growth of Polyensian domesticated plants. Thus, humans burned the forest down right from the get-go.  The combination of human burning for land clearance with rat predation on palm nuts would mean that the forest have a difficult time to grow back on its own.  Recent excavations by a Belgian team up at Vaitea (I believe: I heard about this second hand) show that in prehistory there were attempts to grow these palm trees. This is not at all surprising: the trees were certainly disappearing given activities of slash-and-burn and rat predation and this would be something that prehistoric people noticed (contra the assumptions inherent in claims by Diamond). 

What gets confused as a claim that we (Hunt and Lipo) argued that rats “caused” palm tree extinction are some comments that Hunt made in his paper in American Scientist that:

 

The evidence from elsewhere in the Pacific makes it hard to believe that rats would not have caused rapid and widespread environmental degradation. But there is still the question of how much of an effect rats had relative to the changes caused by humans, who cut down trees for a number of uses and practiced slash-and-burn agriculture. I believe that there is substantial evidence that it was rats, more so than humans, that led to deforestation.

and in his 2007 JAS article where he says:

 

In this review I have examined ar- chaeological, palaeo-environmental, and contemporary eco- logical evidence to suggest that the Pacific rat may have played a major role in Rapa Nui’s ecological catastrophe. The fact that rats alone are capable of widespread forest de- struction compels us to evaluate their contribution to the trans- formation of Rapa Nui, as well as in other island ecosystems. While I argue that the role of rats has often been underesti- mated, direct human actions of felling and use of fire likely have played a significant role as well. Additional research will be essential to disentangle the contributing factors. The environmental catastrophe of Rapa Nui is likely a complex history, one that has been masked by speculations about the in- tentions of people cutting down the last tree. Indeed, the ‘‘last tree’’ may simply have died. Rats may have simply eaten the last seeds. Perhaps the lessons of Rapa Nui tell of the effects of invasive species, invasional meltdowns, and the synergy of ef- fects that ensue as people and their portmanteau biota reach evolutionary isolates in the remote islands of the Pacific. 

But what is clear in the context of these quotes is that what Hunt is arguing (as we both do later on) is that the loss of the forest is the outcome of a number of factors among which rats is one. It is certainly possible to argue that rats could have caused the extinction of the palm trees, but in the case of Rapa Nui it also seems clears that the rat predation was occurring simultaneously with human burning and clearing of the palm forest. Empirically, this is undebatable  as we have rat gnawed seeds that are found contemporaneously with burned palm. 

It is also silly to argue that the presence of non-gnawed seeds somehow “disproves” the role of rat predation. Some nuts probably didn’t get eaten especially if the tree was burned before the rats were able to consume them.  Even a small impact to seed production for these trees is likely to have caused changes in the life history structure of the forest whereby there become fewer and fewer young trees. Rats do not have to eat every single palm nut for the forest to go into major decline or even extinction. Clearly the r-selected strategy of palm trees embodied by nut production is a testament to the fact that the palm is evolutionarily successful by maximizing the number of offspring due to the fact on average some of the nuts will grow into new trees, not all.  The novel introduction of toothed predators likely only had to have a small effect to have upset the balance between forest regeneration and failure. Of course, this is topic that clearly needs more research. 

Question #2:  Canoes and Dolphins: In the second part of his/her question, A Sophist writes: "2. If Palm Trees are unable to be made into canoes, how did the people make ocean going canoes?”  I guess the assumption here is that the presence of dolphin remains at Anakena must somehow have required large ocean going canoes. It also refers to the fact that we argue that palm trees are not useful for constructing canoes, at least not the sailing/voyaging canoes used by Polynesians. To disentangle this question, let’s start by saying that it is likely that whatever canoes brought people to Easter Island were likely around for some period after their arrival. We don’t know this specifically since we have no evidence but the faunal record seems to record more deep water/pelagic fish in the early assemblages than later. The acquisition of these fish would have required canoes and early on there would have been the original canoes to use.  It also seems that at some point these canoes rot away, are lost, or used to sail elsewhere as the faunal remains show significantly less pelagic fish. From that point on the emphasis of the population was nearly entirely on terrestrial resources (though some small % of fish from the limited nearshore reef seemed to supplement the diet). The palm trees appear to have been lost over 4 centuries were not used in canoe manufacturing even though they were present.  This is almost certainly because palm trees are not good raw material for canoes: they are flexible grasses filled with mush. 

The presence of dolphin remains at Anakena is certainly interesting but it doesnt seems to contradict our overall understanding of the archaeological record.  The remains are few in number and were never a major source of food. Ethnographically we know that dolphin come into the Anakena bay and were sometime hunted there. The bay is shallow. Traditional means of hunting dolphin often involved trapping them in shallow water by driving them toward shore with rocks knocked underwater (see http://www.youtube.com/watch?v=QP3FbrF5YyM if you stomach it). Deep water canoes were not necessary for hunting dolphin. 

Final Comment:  The final comment by A Sophist is a bit puzzling: "This seems to be a lesson in how isolated political leaders who do not feel the pain of their actions (cutting down the forest for whatever bloody reason: fuel, canoes, to move statues, etc) can lead their society to the brink of destruction. “ It is not clear at all what “this” refers to or who the “isolated political leaders” are or what “brink of destruction” means. Inherent in here is the idea that somehow the forest was a vital resource upon which people depended. The fact is that there is no evidence that palm trees ever played a central role in the subsistence or settlement activity of people of the island. As sweet potato farmers, the clearance of trees (like all farmers) resulted in more land available for growing crops. The burning of the forest resulted in temporarily increased nutrients in the soil. The fact that rat predation (not to mention the slow growth and reproduction of the tree itself) meant that the forest never regrew was not a catastrophe. Alternative (laborious yet, but indeed clever) means of enriching the soil through rock mulch as well as intensely tended gardens (manavai) were able to keep the soils growing food. The trees simply were not a vital resource to the prehistoric population.

Diamond attempts to defend myths of Easter Island: Lipo and Hunt respond

 

Author Mark Lynas (The God Species: How the planet can survive the age of humans, Six Degrees, High Tide) recently posted a discussion of The Statues That Walked on his blog (www.marklynas.org) -- The myth of Easter Island’s ecocide.  In his essay, Lynas agrees with the basis of our research and concludes:

Like all of us, modern Easter Islanders are inter-dependent with the rest of the world. Perhaps the more recent studies of their history will help challenge the Hobbesian and pessimistic view that human nature necessarily tends towards destruction and violence. Resilience and sustainability are just as likely outcomes, even over the longer term. This, I think, is the true lesson of Easter Island.

His essay states, as we do in TSTW, that ecocide - at least on Easter Island - is a myth and that the evidence contradicts claims made by Jared Diamond (and others).  Interestingly, Jared Diamond (Collapse, Guns, Germs and Steel) chose this forum as a platform to argue against our research and conclusions.  Diamond's letter to Mark's posting is posted in full here.  Below is our response to Diamond's comments.  We have cross posted this here and on Mark Lynas' blog.  Enjoy!

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Diamond attempts to defend myths of Easter Island:  Lipo and Hunt respond

 

We are hardly surprised that Jared Diamond would write that we are “transparently wrong” about Easter Island.  He has a vested interest in defending his “ecocide” storyline published back in 1995 in Discover Magazine and again in his bestselling book Collapse. We acknowledge that Diamond has much at stake here.  But so do the Easter Islanders.  So too does the field of archeology.  And so too does the truth.

Diamond’s thesis about what happened on Easter Island is not new, building as it did on presumptions originally offered by the first Europeans to set foot on the island in the early 18th century. Sadly, this thesis was not challenged because it so conveniently confirmed 18th century prejudice about superior (European) and inferior (everyone not European) societies. Thor Heyerdahl expanded the story and added a further racist twist about lighter-skinned people who accomplished much, and darker-skinned people who incited rebellion, warfare, and ruin.  Diamond simply continues the tradition by reworking the tale to remove the racist elements, relying instead upon an environmental twist put forth by popular writer Paul Bahn and palynologist John Flenley.

An important role of scholarship is to examine long-held myths and see if they hold up under modern scientific tests.  The original Easter Island thesis, in any of its iterations, including Diamond’s, does not.  Let us point out that we didn’t go to Easter Island to tear down Diamond’s thesis. We went there to support it by filling in the missing archeological data. It was only when we convinced ourselves that any iteration of that original story, including Diamond’s, had no archeological evidence to support it and much to contradict it that we began to see where the research was leading us.

It is also important to note that Diamond is not an archaeologist and has not done archaeological or palaeoecological research in Polynesia. We have been doing research and primary archaeological field work on Easter since 2000. One of us (TH) has worked in Pacific Island archaeology for nearly 40 years and taught at University of Hawaii for 23 years.  On Easter Island we have done more field work and covered a greater breadth of archaeology than anyone else in the past two decades.  Our work has been peer-reviewed and published in science’s most selective and prestigious journals.  We outline in detail the evidence from our work and that of scores of colleagues working on the island in our book The Statues that Walked.  Diamond would have readers believe that the majority of archeologists who have studied Easter Island support his thesis.  It is simply not true. The new evidence that we and other serious scholars have provided over the past decade not only contradicts the old story that Diamond has so heavily invested in, but has led to a new consensus among the majority of scholars around our work.

Now, let us deal with the four or five major points of contention.

 

Deforestation

 

Everyone agrees that Easter Island was almost completely deforested by the time Europeans first visited in 1722.  The key issue is causation. In the absence of evidence to refute the facts we lay out, Diamond chooses either to ignore or misrepresent what we do argue. We never argued that rats were the sole cause of deforestation.  As the evidence shows and as we argued in our book, deforestation was a cumulative process that took centuries.  It resulted from rat predation of seeds and from people using fire to clear vegetation for agriculture.

To defend his position that rats played no significant role in deforestation, Diamond cites a study by Mieth and Bork.  Setting aside the fact that even if only a fraction of palm nuts were destroyed by rats, the cumulative effect would have been significant, let’s examine this study on its merits.

We were well aware of the work of Mieth and Bork as we did our work. But we were also aware of the fact (which Diamond fails to point out) that Mieth and Bork based their claim on nut fragments, not whole nuts. Before we rejected this study, we took the time to  experiment ourselves with 25 modern rat-gnawed palm nuts from mainland Chile that we broke into fragments of the sizes resembling those reported by Mieth and Bork.  This sample of 100% whole rat-gnawed nuts--when broken and then counted by their fragments--became a much, much smaller percentage. This shows the problem using Mieth and Bork whose estimate of 10% rat gnawed fragments implies that most nuts (if they were counted whole) were actually gnawed by rats.

Indeed, there is an extensive scientific literature on the impact of rats in island ecosystems that Diamond is either unaware of or simply doesn’t want readers to know about, such as one example from Lord Howe Island, where ecologists point out that without massive programs of rat eradication, the native palms on the island will go extinct. And rats have been on Lord Howe only since 1918, when a steamship ran aground!  Diamond himself, in his own writing, has referred to rats as “agents of extermination” (Diamond 1985).

Bottom line: Diamond needs to explain how, in the absence of predators and with an almost unlimited supply of food, the rat population would have remained small and had no impact on native plants and animals.

Next, Diamond makes the argument that even if rats could do this type of damage, the particular type of trees on Easter Island was not vulnerable to rats. The facts are as follows: Of the 17 major woody species identified from charcoal found in ancient cooking fires, 14 are documented to have seen major rat impacts elsewhere, or to be edible and highly vulnerable.  Furthermore, because the Jubaea palms were slow growing and did not fruit until about 70 years of age, they were particularly vulnerable. Some fraction of new palms would grow, but not enough to replace an entire forest over time.  Older trees would die, many were lost to fire, and in the end it was a losing battle; not enough young seedlings made it to reproductive age.

As for Diamond’s notion that palms were not diminished by rats, but taken down the islanders for rollers to move statues or to carve into canoes, enabling deep-sea fishing, anyone who has seen a palm tree cross-section with its thin, brittle bark and soft fibrous interior would quickly recognize these would not be suitable. Nor frankly would they have been capable of supporting the weight of multi-ton statues as rollers.

As for his allegation that palms were an important part of the islanders’ subsistence, there is overwhelming evidence that the islanders didn’t think so.  As we document in The Statues That Walked on research conducted by Joan Wozniak (2003), Chris Stevenson (Stevenson et al 2002, 2006; Ladefoged  et al. 2005, 2010) and  Hans-Rudolf Bork (Bork et al. 2004) lithic mulch gardens, along with stone-walled gardens known locally as manavai, provided the basis for the islander’s subsistence soon after the island was settled.  Palms provided no direct, long-term benefit so their loss had few if any consequences.

Chronology—When exactly was the island colonized?

One of our most important findings resulted from excavation and radiocarbon dating to establish the date of settlement as 300-800 years later than Diamond’s thesis requires. Diamond insists on missing evidence to argue for a longer chronology.  His argument asks us to accept on faith the notion that “the evidence must be there, we just can’t find it.”  That wouldn’t stand up in court, and it certainly doesn’t stand up in science.  Until such time as serious scientists prove otherwise, there are no reliable radiocarbon dates that support settlement of Easter Island before 1200 A.D. (Hunt and Lipo 2006). To argue otherwise ignores more than 2,000 radiocarbon dates from multiple archipelagos that provide overwhelming evidence that all of the eastern Pacific Islands were settled only over the past thousand years (Rieth et al 2011;Wilmshurst et al 2011), with Easter settled around 1200 A.D.  Even the most skeptical archaeologists working in the Pacific are now quibbling about chronological differences of only 50 to 100 years, not several centuries as Diamond imagines.

Statue Transport---Did the states move horizontally or vertically?

 

Diamond’s thesis hangs on the need for logs to “roll” the statues from the quarries to their final destinations.  In support of his thesis, he asks the reader to “imagine it yourself.”  Surely, he implies, it would be crazy to move a multi-ton statue in a standing position.  And if all you are solely relying upon is your own imagination, it may sound like a scary proposition. But that’s not reason enough to declare some past event as impossible.

But readers need to keep in mind that Diamond’s collapse thesis relies heavily on how the statues were moved.  To sustain his thesis regarding the eventual “collapse” of the ancient society, he needs statue movement to be the “engine” that caused the loss of trees. Decouple the loss of trees from moving statues and the “collapse” story looses steam. Thus, we are not surprised that Diamond holds so tenaciously to old beliefs and discredited claims.

But one has to wonder if Diamond has read The Statues that Walked.  In the book we discuss how fallen statue positions, kinds of breakage, statue shapes with a forward center of mass, as well as statue modifications made between quarry and placement on platforms can only be explained by vertical movement.  As archaeologist and colleague on the island Sergio Rapu (who has studied statues his whole life and has a M.A. degree in archaeology) taught us, the statues were “engineered to move.”  Oral traditions have long insisted that they “walked.” And while some have shown that it is possible to move a statue horizontally on a contraption of logs, (as Diamond posits they were moved) such a method completely ignores the direct and unambiguous evidence provided by the statues themselves.

But there is much better news awaiting readers who might want “to imagine it” themselves.   In recent experiments funded by National Geographic and fully filmed, we “walked” a multi-ton replica of an actual statue (one found along an ancient transport road).  Moving a statue in a standing position is not only possible; it’s relatively easy and can be done with a small group of people using only ropes.  Our experiment will be highlighted in a forthcoming NOVA-National Geographic television special to be broadcast on PBS in the spring of 2012.  Then the rest of the world will see what we have seen—the statues of Easter Island walking upright! Stay tuned!

 

Collapse only after European Contact

 

Again Diamond makes an appeal to authority in lieu of reference to evidence.  He mistakenly says we relied on only one source (Peiser, who does not even appear in our book’s bibliography—again, did he read our book?) who, he points out, has not done any work on the island.  Let us also note once again that Diamond has not conducted any field work on the island.  Nor to our knowledge has one of Diamond’s proclaimed “leading experts,” Paul Bahn, done any field studies on the island.

As we show in The Statues that Walked, rather than repeat assumptions and claims made in the past, we sought direct evidence with no preconceived ideas we needed to defend.  In that frame of mind, what the evidence kept pointing to is that many of the “facts” offered up by so-called “experts” were simply claims repeated over and over and nothing more. The island was certainly transformed over the course of human history (including the dramatic impact of more than 100 years of sheep ranching once the Chileans took control of the island.).  But what is Diamond’s evidence that prehistoric loss of the forest led to cultural and demographic collapse? There is none other than the assumption that losing trees is bad for people living on this island.  Is there evidence of soil erosion? Yes, but it shows re-deposited soils were successfully cultivated. In addition, radiocarbon dating and modern observations show that the most dramatic soil erosion occurred in post-contact and modern times (i.e., largely the results of sheep ranching).  Would the loss of trees have resulted in a critical shortfall of food and/or necessary materials?  The answer is a resounding “no.” Could the palm tree have provided a vital food source for people in the form of nuts? Yes, however, the introduction of tree-dwelling rats meant that these pests would have consumed most of the nuts first.

Diamond repeats a number of traditional notions about the island’s history.  In particular, he cites “evidence of widespread warfare” based on “oral accounts and preserved weapons and skeletal injuries.”  Let’s examine this so-called evidence. First, oral traditions were collected in the 20th century, almost 200 years after European contact.  Alfred Metraux, an anthropologist who studied the islanders’ oral traditions, concluded that they were most likely of very recent origin (Metraux 1940). Katherine Routledge, who worked on the island in the early 20th century, also describes how unreliable and contradictory she found the oral traditions. Our work does not draw upon oral traditions, given their uneven and unknown reliability. Some traditions may well be consistent with what actually happened in the past. In other cases they may not.  It is impossible to evaluate them on their own merits and independent lines of evidence are necessary (e.g., statues “walking” had to be evaluated in terms of evidence beyond just oral traditions).

Diamond’s “preserved weapons,” the mata’a, are agricultural tools that he has chosen to describe as “weapons.”  Their design alone, a rounded to irregular shape, should have been enough to make him question their purpose. But if he had read the microscopic studies reporting edge damage on thousands of these artifacts, he would have seen that the damage they show is consistent with their role in cutting and scrapping plant material (e.g., Church and Ellis 1994).  Indeed, our field studies show that they are found in the greatest concentrations in the lithic mulch gardening areas, right where one would expect to find them. And the island has no fortifications, such as those we see on other Polynesian islands where warfare was frequent.

Diamond points to evidence of violence in human skeletal remains.  However, the published data reveal there are only two cases in which violence appears to have resulted in death, and one of these was an individual who suffered a bullet wound to the head.  The skeletal evidence shows injuries and as we explain in The Statues that Walked, the ancient islanders engaged in some conflicts with one another. But as we outline in our book, statues were a focus of competitive signaling that staved off lethal violence.

Finally, Diamond ignores field research reporting dated domestic habitation sites (see Hunt and Lipo 2009 for discussion). When the habitations are plotted in fifty-year intervals, the number of those occupied clearly shows that the first and only sustained decline, as a relative measure of the population, began only in the first interval following European contact.  Before contact the data show a population that is growing and stabilizing, as reflected in their habitations across the landscape.  There is no evidence of population decline, let alone “collapse” until after European contact.  Indeed, there is direct, abundant evidence that population numbers grew, stabilized, and then fell only after European contact beginning in 1722.

 

The Lesson of Easter Island

 

Rather than address the evidence, Diamond attempts to deride our work by claiming that the people on the dust jacket are not experts in the field.  Diamond is certainly no expert in the field of Easter Island archaeology, regardless of his popularity. The individuals who commented on our book are experts in the areas of human and environmental change, including extensive research in the Pacific Islands.  These well-qualified, highly respected individuals know how science works and are directly engaged in research on ecology, evolution, and environmental change. Lacking quotes by “experts” who we have necessarily challenged in our research (perhaps such as Diamond?)  is certainly no reason for suspicion. The truth of the matter rests in the hands of the reader and the factual evidence outlined in The Statues that Walked.

There are those such as popular writer Paul Bahn and and palynologist John Flenley who continue to push the old doomsday, “ecocide” scenario.  But recent work has shown the central significance of lithic mulch (e.g., Bork et al. 2004; Stevenson et al. 2005; Ladefoged et al. 2010; Wozniak 1999, 2003), the lack of evidence for a 1680 AD “Collapse” event (e.g., Mulrooney et al. 2009, Lipo and Hunt 2009), that mata’a are not developed weapons (Church and Rigney 1994; Church and Ellis 1995), the lack of structural integrity of palms to serve as rollers or use as canoes (e.g., Bork and Meith 2003), the lack of evidence for cannibalism (e.g., McLaughlin 2005), the shorter chronology for colonization not just for Easter, but for the entire eastern Pacific (e.g., Kennett et al. 2006; Reith et al. 2011; Wilmshurst et al. 2008, 2011), the devastating effects that rats have on island environments (e.g., Athens 2009), details about the impact that Europeans had on historic populations (e.g., Fischer 2005), direct evidence about statue transport based on analysis of moai roads (e.g., Lipo and Hunt 2005; Love 2001), the inherently nutrient poor state of soil on Rapa Nui (e.g., Ladefoged 2005) and more.  These findings point to the growing body of evidence that falsifies the basic claims made in favor of “ecocide.” And based on this evidence, the majority of archaeologists working on Easter and elsewhere in Polynesia now reject the notion that the island suffered a pre-European collapse.

Our work in The Statues that Walked brings a wide range of current research into focus and combines more than a decade of our own field and related Easter Island research to form a coherent picture that is the basis of a new scientific consensus.  Easter Island was a story of remarkable success. And as young Native Islanders have told us, knowledge of their ancestors’ success, not failure, matters greatly to them. The “collapse” story for Easter Island is a convenient and popular parable used for shocking the public about the dangers of over-exuberance and environmental disregard.  However, as we describe in our book, the island’s collapse came only with the germs, guns, and enslavement brought by the outside world.  Given what is at stake in terms of lessons to be learned about long-term survival on an isolated and resource poor location, the truth matters.  Indeed, we have much to learn from Easter Island.

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2009 The Myth of AD 1680: New Evidence from Hanga Ho‘onu, Rapa Nui (Easter Island). Rapa Nui Journal 23(2): 94-105

 

Owsley, Douglas W., George W. Gill, and Stephen D. Ousley

1994 Biological effects of European contact on Easter Island. In In the Wake of Contact: Biological Responses to Conquest. C.S. Larsen and G.R. Milner, eds., pp. 161-177. New York: Wiley-Liss.

 

Reith, Timothy M., Terry L. Hunt, Carl P. Lipo, Janet M. Wilmshurst

2011 The Thirteenth Century Polynesian Colonization of Hawai‘i Island Journal of Archaeological Science 38(10): 2740-2749

 

Steadman, David W., Patricia Vargas Casanova, and Claudio Cristino Ferrando

1994 Stratigraphy, Chronology, and Cultural Context of an Early Faunal Assemblage from Easter Island. Asian Perspectives 33(1): 79-96.

 

Stevenson, Christopher M., Thegn Ladefoged, and Sonia Haoa

2002 Productive Strategies in an Uncertain Environment: Prehistoric Agriculture on Easter Island. Rapa Nui Journal 16(1): 17-22.

 

Stevenson, C. M., S. Haoa, T. N. Ladefoged, M. A. Mulrooney, P. M. Vitousek, O. A. Chadwick, and C. Puleston

2010 Evaluating Rapa Nui Prehistoric Terrestrial Resource Degradation. Rapa Nui Journal 24(2): 15-16.

 

Wilmshurst, J.M., T.L. Hunt, C.P. Lipo, and A. Anderson

2011 High precision radiocarbon dating shows recent and rapid initial human colonization of East Polynesia. Proceedings of the National Academy of Sciences USA 108 (5):1815-1820.  http://www.pnas.org/cgi/doi/10.1073/pnas.1015876108

 

Wilmshurst, J.M., A.J. Anderson, T.F.G. Higham, and TH Worthy.

2008 Dating the late prehistoric dispersal of Polynesians to New Zealand using the commensal Pacific rat. Proceedings of the National Academy of Sciences USA 105 (22) 7676–7680. www.pnas.org/cgi/doi/10.1073/pnas.0801507105

 

Wozniak, Joan A.

1999 Prehistoric horticultural practices on Easter Island: lithic mulched gardens and field systems. Rapa Nui Journal 13(3): 95-99.

 

Wozniak, Joan A.

2003 Exploring Landscapes on Easter Island (Rapa Nui) with Geoarchaeological Studies: Settlement, Subsistence, and environmental changes.  Ph.D. Dissertation. University of Oregon, Eugene.

Jared Diamond attempts to defend the myths of Easter Island—

Carl Lipo and Terry Hunt Respond

We are hardly surprised that Jared Diamond would write that we are “transparently wrong” about Easter Island.  He has a vested interest in defending his “ecocide” storyline published back in 1995 in Discover Magazine and again in his bestselling book Collapse. We acknowledge that Diamond has much at stake here.  But so do the Easter Islanders.  So too does the field of archeology.  And so too does the truth.

Diamond’s thesis about what happened on Easter Island is not new, building as it did on presumptions originally offered by the first Europeans to set foot on the island in the early 18th century. Sadly, this thesis was not challenged because it so conveniently confirmed 18th century prejudice about superior (European) and inferior (everyone not European) societies. Thor Heyerdahl expanded the story and added a further racist twist about lighter-skinned people who accomplished much, and darker-skinned people who incited rebellion, warfare, and ruin.  Diamond simply continues the tradition by reworking the tale to remove the racist elements, relying instead upon an environmental twist put forth by popular writer Bahn and palynologist Flenley.

An important role of scholarship is to examine long-held myths and see if they hold up under modern scientific tests.  The original Easter Island thesis, in any of its iterations, including Diamond’s, does not.  Let us point out that we didn’t go to Easter Island to tear down Diamond’s thesis. We went there to support it by filling in the missing archeological data. It was only when we convinced ourselves that any iteration of that original story, including Diamond’s, had no archeological evidence to support it and much to contract it that we began to see where the research was leading us.

It is also important to note that Diamond is not an archaeologist and has not done archaeological or palaeoecological research in Polynesia. We have been doing research and primary archaeological field work on Easter since 2000. One of us (TH) has worked in Pacific Island archaeology for nearly 40 years and taught at University of Hawaii for 23 years.  On Easter Island we have done more field work and covered a greater breadth of archaeology than anyone else in the past two decades.  Our work has been peer-reviewed and published in science’s most selective and prestigious journals.  We outline in detail the evidence from our work and that of scores of colleagues working on the island in our book The Statues that Walked.  Diamond would have readers believe that the majority of archeologists who have studied Easter Island support his thesis.  It is simply not true. The new evidence that we and other serious scholars have provided over the past decade not only contradicts the old story that Diamond has so heavily invested in, but has led to a new consensus among the majority of scholars around our work.

Now, let us deal with the four or five major points of contention.

Deforestation

Everyone agrees that Easter Island was almost completely deforested by the time Europeans first visited in 1722.  The key issue is causation. In the absence of evidence to refute the facts we lay out, Diamond chooses either to ignore or misrepresent what we do argue. We never argued that rats were the sole cause of deforestation.  As the evidence shows and as we argued in our book, deforestation was a cumulative process that took centuries.  It resulted from rat predation of seeds and from people using fire to clear vegetation for agriculture.

To defend his position that rats played no significant role in deforestation, Diamond cites a study by Mieth and Bork.  Setting aside the fact that even if only a fraction of palm nuts were destroyed by rats, the cumulative effect would have been significant, let’s examine this study on its merits.

We were well aware of the work of Mieth and Bork as we did our work. But we were also aware of the fact (which Diamond fails to point out) that Mieth and Bork based their claim on nut fragments, not whole nuts. Before we rejected this study, we took the time to  experiment ourselves with 25 modern rat-gnawed palm nuts from mainland Chile that we broke into fragments of the sizes resembling those reported by Mieth and Bork.  This sample of 100% whole rat-gnawed nuts--when broken and then counted by their fragments--became a much, much smaller percentage. This shows the problem using Mieth and Bork whose estimate of 10% rat gnawed fragments implies that most nuts (if they were counted whole) were actually gnawed by rats.

Indeed, there is an extensive scientific literature on the impact of rats in island ecosystems that Diamond is either unaware of or simply doesn’t want readers to know about, such as those from Lord Howe Island, where ecologists point out that without massive programs of rat eradication, the native palms on the island will go extinct. And rats have been on Lord Howe only since 1918, when a steamship ran aground!  Diamond himself, in his own writing, has referred to rats as “agents of extermination” (Diamond 1985).

Bottom line: Diamond needs to explain how, in the absence of predators and with an almost unlimited supply of food, the rat population would have remained small and had no impact on native plants and animals.

Next, Diamond makes the argument that even if rats could do this type of damage, the particular type of trees on Easter Island were not vulnerable to rats. The facts are as follows: Of the 17 major woody species identified from charcoal found in ancient cooking fires, 14 are documented to have seen major rat impacts elsewhere, or to be edible and highly vulnerable.  Furthermore, because the Jubaea palms were slow growing and did not fruit until about 70 years of age, they were particularly vulnerable. Some fraction of new palms would grow, but not enough to replace an entire forest over time.  Older trees would die, many were lost to fire, and in the end it was a losing battle; not enough young seedlings made it to reproductive age.

As for Diamond’s notion that palms were not diminished by rats, but taken down the islanders for rollers to move statues or to carve into canoes, enabling deep-sea fishing, anyone who has seen a palm tree cross-section with its thin, brittle bark and soft fibrous interior would quickly recognize these would not be suitable. Nor frankly would they have been capable of supporting the weight of multi-ton statues as rollers.

As for his allegation that palms were an important part of the islanders’ subsistence, there is overwhelming evidence that the islanders didn’t think so.  As we document in The Statues That Walked on research conducted by Joan Wozniak (2003), Chris Stevenson (Stevenson et al 2002, 2006; Ladefoged  et al. 2005, 2010) and  Hans-Rudolf (Bork et al. 2004) lithic mulch gardens, along with stone-walled gardens known locally as manavai, provided the basis for the islander’s subsistence soon after the island was settled.  Palms provided no direct, long-term benefit so their loss had few if any consequences.

Chronology—When exactly was the island colonized?

One of our most important findings was excavation and radiocarbon dating to establish the date of settlement as 300-800 years later than Diamond’s thesis requires. Diamond insists on missing evidence to argue for a longer chronology.  His argument asks us to accept on faith the notion that “the evidence must be there, we just can’t find it.”  That wouldn’t stand up in court, and it certainly doesn’t stand up in science.  Until such time as serious scientists prove otherwise, there are no reliable radiocarbon dates that support settlement of Easter Island before 1200 A.D. (Hunt and Lipo 2006). To argue otherwise ignores more than 2,000 radiocarbon dates from multiple archipelagos that provide overwhelming evidence that all of the eastern Pacific Islands were settled only over the past thousand years (Rieth et al 2011;Wilmshurst et al 2011), with Easter settled around 1200 A.D.  Even the most skeptical archaeologists working in the Pacific are now quibbling about chronological differences of only 50 to 100 years, not several centuries as Diamond imagines.

Statue Transport---Did the states move horizontally or vertically?

Diamond’s thesis hangs on the need for logs to “roll” the statues from the quarries to their final destinations.  In support of his thesis, he asks the reader to “imagine it yourself.”  Surely, he implies, it would be crazy to move a multi-ton statue in a standing position.  And if all you are solely relying upon is your own imagination, it may sound like a scary proposition. But that’s not reason enough to declare some past event as impossible.

But readers need to keep in mind that Diamond’s collapse thesis relies heavily on how the statues were moved.  To sustain his thesis regarding the eventual “collapse” of the ancient society, he needs statue movement to be the “engine” that caused the loss of trees. Decouple the loss of trees from moving statues and the “collapse” story looses steam. Thus, we are not surprised that Diamond holds so tenaciously to old beliefs and discredited claims.

But one has to wonder if Diamond has read The Statues that Walked.  In the book we discuss how fallen statue positions, kinds of breakage, statue shapes with a forward center of mass, as well as statue modifications made between quarry and placement on platforms can only be explained by vertical movement.  As archaeologist and colleague on the island Sergio Rapu (who has studied statues his whole life and has a M.A. degree in archaeology) taught us, the statues were “engineered to move.”  Oral traditions have long insisted that they “walked.” And while some have shown that it is possible to move a statue horizontally on a contraption of logs, (as Diamond posits they were moved) such a method completely ignores the direct and unambiguous evidence provided by the statues themselves.

But there is much better news awaiting readers who might want “to imagine it” themselves.   In recent experiments funded by National Geographic and fully filmed, we “walked” a multi-ton replica of an actual statue (one found along an ancient transport road).  Moving a statue in a standing position is not only possible; it’s relatively easy and can be done with a small group of people using only ropes.  Our experiment will be highlighted in a forthcoming NOVA-National Geographic television special to be broadcast on PBS in the spring of 2012.  Then the rest of the world will see what we have seen—the statues of Easter Island walking upright! Stay tuned!

Collapse only after European Contact

Again Diamond makes an appeal to authority in lieu of reference to evidence.  He mistakenly says we relied on only one source (Peiser, who does not even appear in our book’s bibliography—again, did he read our book?) who, he points out, has not done any work on the island.  Let us also note once again that Diamond has not conducted any field work on the island.  Nor to our knowledge has one of Diamond’s proclaimed “leading experts,” Paul Bahn, done any field studies on the island.

As we show in The Statues that Walked, rather than repeat assumptions and claims made in the past, we sought direct evidence with no preconceived ideas we needed to defend.  In that frame of mine, what the evidence kept pointing to is that many of the “facts” offered up by so-called “experts” were simply claims repeated over and over and nothing more. The island was certainly transformed over the course of human history (including the dramatic impact of more than 100 years of sheep ranching once the Chileans took control of the island.).  But what is Diamond’s evidence that prehistoric loss of the forest led to cultural and demographic collapse? There is none other than the assumption that losing trees is bad for people living on this island.  Is there evidence of soil erosion? Yes, but it shows re-deposited soils were successfully cultivated. In addition, radiocarbon dating and modern observations show that the most dramatic soil erosion occurred in post-contact and modern times (i.e., largely the results of sheep ranching).  Would the loss of trees have resulted in a critical shortfall of food and/or necessary materials?  The answer is a resounding “no.” Could the palm tree have provided a vital food source for people in the form of nuts? Yes, however, the introduction of tree-dwelling rats meant that these pests would have consumed most of the nuts first.

Diamond repeats a number of traditional notions about the island’s history.  In particular, he cites “evidence of widespread warfare” based on “oral accounts and preserved weapons and skeletal injuries.”  Let’s examine this so-called evidence. First, oral traditions were collected in the 20th century, almost 200 years after European contact.  Alfred Metraux, an anthropologist who studied the islanders’ oral traditions, concluded that they were most likely of very recent origin (Metraux 1940). Katherine Routledge, who worked on the island in the early 20th century, also describes how unreliable and contradictory she found the oral traditions. Our work does not draw upon oral traditions, given their uneven and unknown reliability. Some traditions may well be consistent with what actually happened in the past. In other cases they may not.  It is impossible to evaluate them on their own merits and independent lines of evidence are necessary (e.g., statues “walking” had to be evaluated in terms of evidence beyond just oral traditions).

Diamond’s “preserved weapons,” the mata’a, are agricultural tools that he has chosen to describe as “weapons.”  Their design alone, a rounded to irregular shape, should have been enough to make him question their purpose. But if he had read the microscopic studies reporting edge damage on thousands of these artifacts, he would have seen that the damage they show is consistent with their role in cutting and scrapping plant material (e.g., Church and Ellis 1994).  Indeed, our field studies show that they are found in the greatest concentrations in the lithic mulch gardening areas, right where one would expect to find them. And the island has no fortifications, such as those we see on other Polynesian islands where warfare was frequent.

Diamond points to evidence of violence in human skeletal remains.  However, the published data reveal there are only two cases in which violence appears to have resulted in death, and one of these was an individual who suffered a bullet wound to the head.  The skeletal evidence shows injuries and as we explain in The Statues that Walked, the ancient islanders engaged in some conflicts with one another. But as we outline in our book, statues were a focus of competitive signaling that staved off lethal violence.

Finally, Diamond ignores field research reporting dated domestic habitation sites (see Hunt and Lipo 2009 for discussion). When the habitations are plotted in fifty-year intervals, the number of those occupied clearly shows that the first and only sustained decline, as a relative measure of the population, began only in the first interval following European contact.  Before contact the data show a population that is growing and stabilizing, as reflected in their habitations across the landscape.  There is no evidence of population decline, let alone “collapse” until after European contact.  Indeed, there is direct, abundant evidence that population numbers grew, stabilized, and then fell only after 1722.

The Lesson of Easter Island

Rather than address the evidence, Diamond attempts to deride our work by claiming that the people on the dust jacket are not experts in the field.  Diamond is certainly no expert in the field of Easter Island archaeology, regardless of his popularity. The individuals who commented on our book are experts in the areas of human and environmental change, including extensive research in the Pacific Islands.  These well-qualified, highly respected individuals know how science works and are directly engaged in research on ecology, evolution, and environmental change. Lacking quotes by “experts” who we have necessarily challenged in our research (perhaps such as Diamond?)  is certainly no reason for suspicion. The truth of the matter rests in the hands of the reader and the factual evidence outlined in The Statues that Walked.

There are those such as popular writer Paul Bahn and and palynologist John Flenley who continue to push the old doomsday, “ecocide” scenario.  But recent work has shown the central significance of lithic mulch (e.g., Bork et al. 2004; Stevenson et al. 2005; Ladefoged et al. 2010; Wozniak 1999, 2003), the lack of evidence for an 1680 AD “Collapse” event (e.g., Mulrooney et al. 2009, Lipo and Hunt 2009), that mata’a are not developed weapons (Church and Rigney 1994; Church and Ellis 1995), the lack of structural integrity of palms to serve as rollers or use as canoes (e.g., Bork and Meith 2003), the lack of evidence for cannibalism (e.g., McLaughlin 2005), the shorter chronology for colonization not just for Easter, but for the entire eastern Pacific (e.g., Kennett et al. 2006; Reith et al. 2011; Wilmshurst et al. 2008, 2011), the devastating effects that rats have on island environments (e.g., Athens 2009), details about the impact that Europeans had on historic populations (e.g., Fischer 2005), direct evidence about statue transport based on analysis of moai roads (e.g., Lipo and Hunt 2005; Love 2001), the inherently nutrient poor state of soil on Rapa Nui (e.g., Ladefoged 2005) and more.  These new findings point to the growing body of evidence that falsifies the basic claims made in favor of “ecocide.” And based on this evidence, the majority of archaeologists working on Easter and elsewhere in Polynesia now reject the notion that the island suffered a pre-European collapse.

Our work in The Statues that Walked brings a wide range of current research into focus and combines more than a decade of our own field and related Easter Island research to form a coherent picture that is the basis of a new scientific consensus.  Easter Island was a story of remarkable success. And as young Native Islanders have told us, knowledge of their ancestors’ success, not failure, matters greatly to them. The “collapse” story for Easter Island is a convenient and popular parable used for shocking the public about the dangers of over-exuberance and environmental disregard.  However, as we describe in our book, the island’s collapse came only with the germs, guns, and enslavement brought by the outside world.  Given what is at stake in terms of lessons to be learned about long-term survival on an isolated and resource poor location, the truth matters.  Indeed, we have much to learn from Easter Island.

References

Athens, Stephen

2009 Rattus exulans and the catastrophic disappearance of Hawai'i's native lowland forest. Biological Invasions 11: 1489-1501.

Auld T.D., Hutton I., Ooi M.K.J., Denham A.J.

2010 Disruption of recruitment in two endemic palms on Lord Howe Island by invasive rats. Biological Invasions 12: 3351-3361

Bork, Hans-Rudolf, Andreas Mieth, and Bernd Tschochner

2004 Nothing but stones? A review of the extent and technical efforts of prehistoric stone mulching on Rapa Nui. Rapa Nui Journal 18(1): 10-14.

Butler, K. R., C. R. Prior, and J. R. Flenley

2004 Anomalous radiocarbon dates from Easter Island.  Radiocarbon 46(1): 395-405.

Campbell, D. J., Atkinson, I. A. E.

2002 Depression of tree recruitment by the Pacific rat (Rattus exulans Peale) on New Zealand’s northern offshore islands. Biological Conservation 107:19-35.

Church, Flora, and Grace Ellis

1996 A use-wear analysis of obsidian tools from an Ana Kionga. Rapa Nui Journal 10(4): 81-88.

Church, F., and J. Rigney

1994 A microwear analysis of tools from site 10-241, Easter Island--An inland processing site. Rapa Nui Journal 8(4): 101-105.

Diamond, J.

1985 Rats as agents of extermination. Nature 318: 602-603.

Drake, D.R. and T. L. Hunt

2009 Invasive rodents on islands: integrating historical and contemporary ecology. Biological Invasions 11: 1483-1487.

Fischer, Steven R.

2005 Island at the End of the World: The turbulent history of Easter Island. London: Reaktion Books.

Hunt, T. L., and C. P. Lipo

2006 Late colonization of Easter Island. Science 311(5767): 1603-1606.

Hunt, T.L. and C.P. Lipo

2009 Revisiting Rapa Nui (Easter Island) “Ecocide.” Pacific Science 63: 601-616.

Kennett, Douglas, et al.

2006 Prehistoric human impacts on Rapa, French Polynesia. Natural History 80 (October 2004): 340-354.

Ladefoged, T. N., C. M. Stevenson, S. Haoa, M. Mulrooney, C. Puleston, P. M. Vitousek and O.A. Chadwick

2010 Soil nutrient analysis and Rapa Nui gardening. Archaeology in Oceania 45:80-85.

Lipo, Carl. P., and Terry L. Hunt

2005 Mapping prehistoric statue roads on Easter Island. Antiquity 79:158-168.

Lipo, C. P. and T. L. Hunt

2009 AD 1680 and Easter Island Prehistory.  Asian Perspectives. 48(2): 309-317.

McLaughlin, S.

2005 Cannibalism and Easter Island: Evaluation, Discussion of Probabilities, and Survey of the Literature on the Subject.  Rapa Nui Journal 19(1): 30-50.

Métraux, Alfred

1940 Ethnology of Easter Island. Honolulu: Bulletin, 160, Bernice P. Bishop Museum.

Mulrooney, M. A., T. N. Ladefoged, C. M. Stevenson, and S. Haoa,

2009 The Myth of AD 1680: New Evidence from Hanga Ho‘onu, Rapa Nui (Easter Island). Rapa Nui Journal 23(2): 94-105

Owsley, Douglas W., George W. Gill, and Stephen D. Ousley

1994 Biological effects of European contact on Easter Island. In In the Wake of Contact: Biological Responses to Conquest. C.S. Larsen and G.R. Milner, eds., pp. 161-177. New York: Wiley-Liss.

Reith, Timothy M., Terry L. Hunt, Carl P. Lipo, Janet M. Wilmshurst

2011 The Thirteenth Century Polynesian Colonization of Hawai‘i Island Journal of Archaeological Science 38(10): 2740-2749

Steadman, David W., Patricia Vargas Casanova, and Claudio Cristino Ferrando

1994 Stratigraphy, Chronology, and Cultural Context of an Early Faunal Assemblage from Easter Island. Asian Perspectives 33(1): 79-96.

Stevenson, Christopher M., Thegn Ladefoged, and Sonia Haoa

2002 Productive Strategies in an Uncertain Environment: Prehistoric Agriculture on Easter Island. Rapa Nui Journal 16(1): 17-22.

Stevenson, C. M., S. Haoa, T. N. Ladefoged, M. A. Mulrooney, P. M. Vitousek, O. A. Chadwick, and C. Puleston

2010 Evaluating Rapa Nui Prehistoric Terrestrial Resource Degradation. Rapa Nui Journal 24(2): 15-16.

Wilmshurst, J.M., T.L. Hunt, C.P. Lipo, and A. Anderson

2011 High precision radiocarbon dating shows recent and rapid initial human colonization of East Polynesia. Proceedings of the National Academy of Sciences USA 108 (5):1815-1820.

www.pnas.org/cgi/doi/10.1073/pnas.1015876108

Wilmshurst, J.M., A.J. Anderson, T.F.G. Higham, and TH Worthy.

2008 Dating the late prehistoric dispersal of Polynesians to New Zealand using the commensal Pacific rat. Proceedings of the National Academy of Sciences USA 105 (22) 7676–7680. www.pnas.org/cgi/doi/10.1073/pnas.0801507105

Wozniak, Joan A.

1999 Prehistoric horticultural practices on Easter Island: lithic mulched gardens and field systems. Rapa Nui Journal 13(3): 95-99.

Wozniak, Joan A.

2003 Exploring Landscapes on Easter Island (Rapa Nui) with Geoarchaeological Studies: Settlement, Subsistence, and environmental changes.  Ph.D. Dissertation. University of Oregon, Eugene.

The Statues That Walked

Just got the jacket cover material for "The Statues That Walked"

The monumental statues of Easter Island, both so magisterial and so forlorn, gazing out in their imposing rows over the island’s barren landscape, have been the source of great mystery ever since the island was first discovered by Europeans on Easter Sunday, 1722.   How could the ancient people who inhabited this tiny speck of land, the most remote in the vast expanse of the Pacific islands, have built such monumental works?  No such astonishing numbers of massive statues are found anywhere else in the Pacific. How could the islanders possibly have moved so many multi-ton monoliths from the quarry inland where they were carved to their posts along the coastline?  And most intriguing, and vexing, of all, if the island once boasted a culture developed and sophisticated enough to have produced such marvelous edifices, what happened to that culture?  Why was  the island the Europeans discovered a sparsely populated wasteland?

The prevailing accounts of the history of the island tell a story of self-inflicted devastation; a glaring case of eco-suicide.  The island was dominated by a powerful chiefdom that promulgated a cult of statue-making, exercising a ruthless hold on the island’s people and rapaciously destroying the environment, cutting down a lush palm forest that once blanketed the island in order to construct contraptions for moving more and more statues that grew larger and larger.  As the population swelled in order to sustain the statue cult, growing well beyond the island’s agricultural capacity, a vicious cycle of warfare broke out between opposing groups, and the culture ultimately suffered a dramatic collapse.

When Terry Hunt and Carl Lipo began carrying out archeological studies on the island in 2003, they fully expected to find evidence supporting this account.  But instead, revelation after revelation uncovered a very different truth.  In this lively and fascinating account of their definitive solution to the mystery of what really happened on the island, they introduce the striking series of archeological discoveries they made, and the path-breaking findings of others about the history of the Pacific islands, which led them to compelling new answers to the most perplexing questions.  Far from irresponsible environmental destroyers, they show, the Easter Islanders were remarkably inventive environmental stewards, devising ingenious methods to enhance the island’s agricultural capacity.   They did not devastate the palm forest, and the culture did not descend into brutal violence.  Perhaps most surprising of all, the making and moving of their enormous statutes did not require a bloated population or tax their precious resources; their statue-building was actually integral to their ability to achieve a delicate balance of sustainability.  The Easter Islanders, it turns out, offer us an impressive record of masterful environmental management rich with lessons for confronting the daunting environmental challenges of our own time.

Shattering the conventional wisdom, Hunt and Lipo’s iron-clad case for a radically different understanding of the story of this most mysterious place is scientific discovery at its very best.

Rats! (and German Ecologists)

Today's USA Today covers a new paper that is just being published in the Journal of Archaeological Science by ecologists Andreas Mieth and Hans-Rudolph Bork from the Institute for Ecosystem Research in Kiel, Germany. This paper "Humans, climate or introduced rats – which is to blame for the woodland destruction on prehistoric Rapa Nui (Easter Island)?" challenges Terry Hunt and my argument that (1) Easter Island was colonized in AD 1200 and (2) that rats played a role in transforming the ecology of the island.

Their argument sets up our previous work as a "straw man." They claim that we argued that rats *only* caused these trees to go extinct. This is, of course, absurd - trees were primarily destroyed by burning, not rats. Rats, however, must have had some impact on the environment simply because (1) they were there, having been introduced when people arrived (2) rat populations must have been large, based on the lack of natural predators and the plethora of food provided by the Jubaea chilensis palm (i.e., nuts). All we are saying is that this aspect needs to be considered when putting together the overall explanation.  

The real point of contention is what prevented regeneration of the forest, not what cut it down. The fact that there was no forest regeneration is fairly clear from archaeological evidence (made by a variety of folks). While we see prehistoric sedimentation, we don't see palm root molds other than those made in the pre-human occupation surfaces. Mieth and Bork, following the standard "catastrophe" story believe that the lack of regeneration is due to erosion and ecological collapse. I would argue that rats would have made it difficult, if not impossible for the trees to regrow - and that humans would have had little incentive to regrow these slow growing trees (Jubea palm live up to 500 years) especially since any new trees would harbor more rats. Much of the differences in these stances has to do with what one assumes the productivity of the wooded environment was like -- they assume that the productivity was high (because it was forested). I think the evidence speaks otherwise.

I've been working hard on this part of the story for the book - it forms the focus of a chapter we call "Resilience." Where this covers the conditions that prehistoric populations faced when they arrived on the island, the materials/technology/plants/animals they had with them, and the details of the history resulting from this combination. It's coming together...

Below is what I do not think is the case. It just didn't happen. More on this later...

++= ?

Questioning Collapse

The marketing folks at Cambridge have set up a web site for the Questioning Collapse edited volume. The website is basically a blog (built on wordpress) that allows students/reviewers to interact and pose questions -- as well as provide information about the authors and their research. It's a good way to promote a book, I think, since some of the aspects of reading the book are going to generate questions and challenges. Exactly how individuals will find out about the web site is a little more mysterious (thus, my link here.). I wonder if books have facebook pages. Although there isn't much in the way of content at the site now, it should grow pretty quickly.

Questioning Collapse Web Site

Colonization of Easter Island - and implications.

I have posted the poster that Terry Hunt and I plan to present at the Society for American Archaeology meetings in Austin, TX this week. You can download a pdf of the poster here. This poster presents an extended argument about the timing of the colonization of Easter Island (Rapa Nui). We suggest that the island was not occupied until about AD 1200, about 500 years after the "traditional" date of AD 700-900. While it might seem like a small point, this change in the chronology has rippling significance to the standard "collapse" story told by Flenley, Bahn, Diamond and others. What the date means is that there is only about 500 years for the entire prehistory of Easter Island - prior to Easter Sunday in AD 1722 when Roggeveen arrives on the island. 500 years for occupation, "climax," "collapse," and then rebound - if one is to accept the traditional story. One might think that this alone should present questions about the chronology as we present it. "If collapse occurred, then the short chronology can't be right." In fact, this is what a number of colleagues appear to believe and are arguing in print (Bahn and Flenley are publishing such a statement in the upcoming issue of Rapa Nui Journal). As it turns out, it appears that many researchers have worked backwards - while we have concrete evidence (as argued in the poster) for the "short" chronology, we don't have evidence for a "collapse" - at least pre-European arrival. This might seem odd to many as many assume that the story of collapse is one that is "obvious" or "certain." It's not. The problem here is a mixing of evidence and belief. This has resulted in what we term "belief based" archaeology for Easter Island. Researchers have made many claims about the prehistory of the islands but a remarkably large number of them are based on inferences derived from the story itself (i.e., circular reasoning). We do know without any reasonable doubt that there were large numbers of palm trees on the island prior to humans arriving. We also know at some point all of the trees went extinct. What we don’t know is the chronological and functional relations between humans and plants that resulted in the loss of trees. Lacking much of the basic evidence, a set of beliefs have been established and perpetuated that rationalize the story. For example: What is the connection between trees and people? Belief: Trees were used to move statues around (this is stated primarily because its assumed that this is why the trees went away) Evidence: We don’t know. We don’t even have evidence that the extinct palms were capable of moving statues around given that many of the related taxa have big mushy interiors. How did statues get moved? Belief: Trees used as levers or rollers Evidence: We don’t know but evidence points more towards the fact that they were “walked” rather than rolled. How many people were on the island in prehistory (at maximum)? Belief: 10-20,000 people because that’s the number assumed that were required for organizational structures to manipulate the movement of statues. Evidence: We don’t know though the number at contact is reported at 3-4,000 and the settlement patterns are largely dispersed rather than nucleated. When did people arrive on the island? Belief: 700-900AD because that is the amount of time it would take to get to 10-20,000 people Evidence: Looking critically at dates we can accept based on standard practices, we find that evidence points to 1200AD. This means that only 500 years passes before Europeans arrive (AD1722). When did the “collapse” occur? Belief: some several hundred years prior to European contact in AD1722. This gap is thought to occur to account for the well-fed and robust nature of the population in 1722 (i.e., post collapse) . Evidence: There is no evidence of prehistoric collapse. People were healthy in 1722, prior to that we simply don’t know but nothing exists to suggest cannibalism, warfare, catastrophe. Collapse certain did occur after 1722 – we have records of that (and was caused by disease and other dramatic population changes). How did people fight with one another? Belief: Obsidian bifaces called “mataa” are found all over the place. These were weapons. Evidence: The shape of the mataa are such that they would make terrible weapons. While there are few that are pointy, the vast majority are oddly shaped and have no pointed end. Their shape and usewear is consistent with cutting (if it were for stabbing one would expect significant impact damage on the tips – but that is not the case). Skeletal evidence also shows little evidence for traumatic injuries – skeletons exhibit non-lethal trauma.- How did people destroy their landscape? Belief: By cutting down the trees, the people “began a downward spiral” to cultural catastrophe – erosion and carrying capacity vanished. Evidence: Given known archaeological rat populations (we find them in all of the early layers) palm trees may not have been useful subsistence source – and may have harbored millions of rats. Polynesians who arrived on the island were cultivators – farmers – who relied on plants like the sweet potato, sugar cane, bananas. Thus its not clear there was a necessary relation between people and palm trees (other than the negative aspect of having them filled with rats eating the palm nuts). As for erosion – we know it occurred – but given the fact that the archaeological record is largely surficial over all (you can find mataa, obisidian flakes, groundstone every where) it doesn’t seem to have been prehistoric. Indeed, much of the major erosion seems to be a function of the 100 years of sheep ranching and other historic activities (most by Europeans). There are many more examples of a belief structure that focuses on "collapse" and "environmental overshoot" guiding what people perceive the evidence to be on Easter Island. All of these need to be carefully examined so that we can distinguish aspects of the archaeological record from the stories being spun about it.