Carl Linnaeus end of his life he timidly advanced the hypothesis that all the species of one genus constituted at the creation one species; and from the last edition of his "Systema Naturæ" he quietly left out the strongly orthodox statement of the fixity of each species, which he had insisted upon in his earlier works. ... warnings came speedily both from the Catholic and Protestant sides. The mathematical PageRank algorithm, applied to 24 multilingual Wikipedia editions in 2014, published in "PLOS ONE" in 2015, placed Carl Linnaeus at the top historical figure, above Jesus, Aristotle, Napoleon, and Adolf Hitler (in that
Carl Linnaeus the idea of a hierarchical structure of classification which is based upon observable characteristics and intended to reflect natural relationships. While the underlying details concerning what are considered to be scientifically valid "observable characteristics" have changed with expanding knowledge (for example, DNA sequencing, unavailable in Linnaeus' time, has proven to be a tool of considerable utility for classifying living organisms and establishing their evolutionary relationships), the fundamental principle remains sound. Linnaeus' system of taxonomy was especially noted as the first to include humans ("Homo") taxonomically grouped with apes ("Simia"), under the header of "Anthropomorpha". German biologist Ernst Haeckel speaking in