Figures 3 and 4 of this paper were switched in the initial release of the book reporting on IAU Colloquium No. 88; the plot above the Fig. 3 caption should be above the Fig. 4 caption and vice versa. This was corrected in some, but not all, of the books distributed after the error was discovered.
Author comment submitted on 9 March, 2017 by Wayne Osborn ( Wayne.Osborn@cmich.edu )