the philosophical questions raised by multiple, visually similar species being considered as one have come up before. Zebras were discovered to be 3 separate sp

the philosophical questions raised by multiple, visually similar species being considered as one have come up before. Zebras were discovered to be 3 separate species. See "What, if anything, is a Zebra?" from 1983 http://polaris.gseis.ucla.edu/gleazer/462_readings/gould.pdf http://polaris.gseis.ucla.edu/gleazer/462_readings/gould.pdf