Ambiguity from Easter Island:
I occasionally cite the population history of Easter Island as an example of an isolated population that gets too big and then collapses.  There was even a nice graph of the time course. (Chapter 2 Terry L. Hunt and Carl P. Lipo ”Ecological Catastrophe, Collapse, and the Myth of “Ecocide” on Rapa Nui,” Questioning Collapse, Cambridge University Press, Cambridge 2010)

Alas for rhetorical impact, the time scale is off by about a factor of two, so I have been obliged to do a little hand waving and insist that the occupants of that island were not in fact a randomly mating community and anyway it is likely, but not clear, that the population never actually reached lethal levels. 

Now (Terry L. Hunt Easter Island’s Complex History NATURE vol. 479 no. 7371 November 3, 2011 page 41) it is suggested that the island was settled later than had been thought, never had a population collapse before Europeans even though the graph I cite shows one and then a second one starting, and that building statues prevented mass violence.  I suspect they had their violence, but I have no new data on that.  And I have the suspicion that the statues were not a means of staving off violent interactions but of staving off more tender and dangerous interactions.  They identified families and kept the total size of the mating pools viable. 

So I think, but now given that there is serious debate about just what was going on, the use of Easter Island as an example is seriously compromised.  The logic will have to go away.  Once more people understand about kinship and fertility they can apply it to that location.

There have been 32,327 visitors so far.

Home page