I would be very interested in seeing the studies that show what is in the dust in Kenya compared to the dust in Hawaii. If the Hawaiian ones eat more snails I would think that calcium shouldn't be an issue.
I would also like to know how they determined the horn differences and body size of the Hawaiian ones is from inbreeding and had no environmental influence.
(There was spraying done quite a few years ago to kill coqui frogs in Hawaii...I wonder if that could have had any affect on the chameleons. I know it was thought to be killing some...but maybe it caused problems for the ones that didn't get enough of it to kill them?)