In Frank Wiley’s analysis of the size comparison of the ivorybill and the pileated . . . [t]he ivorybill isn’t “29% larger” as he calculated and published, but 40% larger.

Someone else may have already commented on that bad math, but I have not yet uncovered it on your website.  Thus, I will explain.  And pardon my lateness if this has already been laid to rest.

The baseline measurement is the pileated at 100 pixels body length.  The ivorybill is 140 pixels.  Thus, the proper math for saying, “The ivorybill is x% longer in body length than the pileated” is 140/100 = 1.40.  Proper statements then become, “The ivorybill is a factor of 1.4 longer in body length than the pileated,” or “The ivorybill is 40% longer in body length than the pileated.”  (Two ways of saying the same thing.)  Frank took the reverse approach with his math, which is fine(!), but then he put it into words wrong.  He would have been right if he had said, “The pileated is 29% shorter in body length than the ivorybill,” or “The pileated’s body length is 71% that of the ivorybill.”  (Again two ways of saying the same thing.  And also the same thing as saying the flip side using the 1.4 factor or 40% longer.)