A fascinating talk on this subject was given in the Long Now series a little while back: http://longnow.org/seminars/02013/jan/17/statues-walked-what-really-hap

A fascinating talk on this subject was given in the Long Now series a little while back: http://longnow.org/seminars/02013/jan/17/statues-walked-what-really-happened-easter-island/ http://longnow.org/seminars/02013/jan/17/statues-walked-what... . Highly recommended.