Thursday, September 22, 2011

Jared Diamond dismantles Lynas: How to politely devastate a "skeptic" loon

Passersby were astonished by the unusually large amount of blood. Diamond sets right to work:

 Among Hunt’s and Lipo’s main conclusions, they say that Easter Island was deforested by rats, not by Polynesian settlers; that settlement was not until AD 1200 rather than earlier as widely assumed; that the tall stone statues of up to 90 tons were not transported horizontally, but were “walked” upright; that the collapse of Easter society was due to European impact, rather than to impacts of the settlers themselves before European arrival; and that the view of Easter society’s collapse as a self-inflicted ecological catastrophe is flawed. Unfortunately, the web postings don’t recognize the compelling reasons why Hunt’s and Lipo’s conclusions are considered transparently wrong by essentially all other archaeologists with active programs on Easter Island.
A "skeptic" with no experience of a given area of scholarship uncritically embracing a single source that claims to overturn all that went before, despite being regarded as  "transparently wrong" by the vast majority of qualified experts? Come on, that would never happen.

The initial reason for positing a role of rats in Easter’s deforestation was that some preserved seeds of Easter’s extinct palm tree, found in caves, show marks of gnawing by rats; and that a study of Hawaii attributed deforestation there to rats. However, evidence that rats played no significant role in Easter’s deforestation includes the following.  Rats occur not only on Easter but also on every other one of the hundreds of other Polynesian islands, most of which nevertheless did not end up deforested.  Over 90% of preserved palm seeds outside caves were not gnawed by rats.  Easter’s forest consisted not only of the palm but also of at least two dozen other species of trees and other plants, all of which also became extinct on Easter although most of them are not known to suffer seed predation by rats and continue to exist in the presence of rats on other Polynesian islands.
So we have "skeptics" who spin an entire narrative out of a single fact: there are some seeds in some caves, some of which were gnawed by rats. They then ignore the larger body of evidence and neglect the basic obligation of any scientist presenting a hypothesis to account for all the facts. Have we seen something like this somewhere before?

How could tall 90-ton statues have been dragged over unpaved hilly terrain?  The only reasonable solution, to avoid their tipping and breaking during transport, is to transport them horizontally and then lever them into an upright position.  Jo Anne Van Tilburg, the leading scholar of Easter statues, who has spent decades cataloging the hundreds of statues, carried out an experiment in which Easter Islanders demonstrated for her their horizontal transport and levering-up of a model statue.  But Hunt and Lipo claim that statues were transported vertically.  This seems an implausible recipe for disaster.  Imagine it yourself: if you were told to transport a 90-ton statue 33 feet high over a dirt road, why would you risk tipping and breaking it by transporting it vertically with all its weight concentrated on its small base, rather than avoiding the risk of tipping by laying it flat and distributing its weight over its entire length?
 Hunt and Lipo think that these statues "waddled" -- in all their 33-foot-tall glory -- up and down unpaved hills. As Diamond says, imagine it. But the problem here is not Hunt and Lipo having dumb ideas -- it's people like Lynas and Curry who spread this stuff to their many devoted fans, without any effort to assess critically the claims of the "skeptics."

This underscores that lukewarmism is not and never has been about a particular stance in relation to the science of global warming. Unfortunately, just like its cousin, denialism, it's about a particular attitude and approach to a given field. It's not primarily a set of erroneous conclusions, but an erroneous method motivated by partisanship.

Postscript on Peiser, Lynas' other crappy source: In a statement against interest by Lynas, a statement I don't know whether to praise for its honesty or condemn for its bald admission of indifference to the use of scholarly garbage, Lynas in his own comments basically admits Benny Peiser is a hack:

Actually Peiser’s paper was published in a special edition of E&E which was specifically devoted to taking apart Diamond’s ‘Collapse’ book, so fitted well into that. (I haven’t read any of the rest of it because Oxford University doesn’t subscribe to E&E!) [Memo to Lynas: Oxford is a thousand-year-old world-famous university with tens of thousands of journal subscriptions -- if they don't even carry the journal you are using to form the tentpole of your argument, that is a red flag.] I think the edition was guest edited by Julian Morris and Kendra Okonski – both very much anti-environment activists, latterly with the ‘International Policy Network’ (now defunct I think) and very much in the ‘climate denial’ line. So not great credentials…[No, really?] but that still doesn’t make the paper wrong – it should be judged on its own merits. Plus, I wouldn’t have given it so much weight except for the Hunt and Lipo book – which does seem very solid in terms of the fieldwork, and has also seen material published in the ‘right’ (specialist) journals. [Well, we know how that turned out for you.]
 Not a great day for Mark and his Curry-endorsed "opening mind," but here's hoping he learned from the experience.


  1. method motivated by partisanship

    It strikes me as more a form of Broderism. Certainly motivated by a desire to see the physical world conform to political biases in any case.

    I like to think of lukewarmism as the bargaining phase. Or maybe the hunt for the elusive compromise theory. Mostly the former, though, and I think a few of the other stages of grief have anologous reactions to undesirable information.