The first phylogeny 30 Sep 202030 Sep 2020 The only diagram in the Origin is famously the hypothetical series of species forming a tree structure, but it isn’t an actual classification based on his principles. I have previously noted the rise of cladograms towards the end of the 19th century, but in a talk by Ian Hesketh, I was drawn to the following cladogram by Fritz Müller in his Für Darwin, in 1864, a mere 5 years after the Origin was published. And it even uses a distinction between homologous ancestral characters in distinction to what we now call conversantly evolved characters. Here it is in the English translation paid for by Darwin himself in 1869. The organisms being discussed here are amphipods of the genus Melita, of which there are around 80 species known today. Müller points out that genera are often created using characters like the secondary flagella of the antenna, which is variable, while the asymmetric clasping structure is shared by five species. So he classifies the relationships between the species using the clasp rather than the antennae. This is, to the best of my knowledge, the first classification using common descent as the principle, making a distinction between what we now call apomorphies and plesiomorphies, after Hennig. Darwin sketched a few, but did not publish them, and anyway his methodology was not so clear as Müller’s. By contrast with Muller, Haeckel’s grandiose trees in the Generelle Mophologie in 1866 showed no evidence of understanding clearly what Müller had done. So is this the earliest cladogram? Can anyone point to another? Thanks Evolution Natural Classification Systematics
Evolution Some more on that snake leg 17 Sep 2009 Lanclet, discussing a Jerry Coyne comment on a Pharyngula post, suggests that the snake actually had ingested a lizard, and the lizard’s leg had punctured the snake. It doesn’t change the point about atavisms, but it does make the case less sexy… Read More
Evolution Evolution quotes: Quetelet on populations 12 Jan 201212 Jan 2012 Populations arise imperceptibly; it is only when they have reached a certain degree of development that we begin to think of their existence. This increase is more or less rapid, and it proceeds either from an excess of births over deaths, or from immigrations, or both. In general, it is… Read More
A year on, 1865, Mivart made a decent stab at it, covered in detail here: http://www.isita-org.com/jass/Contents/2011vol89/e-pub/21368345.pdf and Craw wrote about Muller’s work, Craw, RC (1992). “Margins of cladistics: Identity, differences and place in the emergence of phylogenetic systematics”. In Griffiths, PE (ed.). Trees of life: Essays in the philosophy of biology. Dordrecht: Kluwer Academic. pp. 65–107. Another year, 1866, and there is Albert Gaudry (Tassy writes about him: https://doi.org/10.1016/j.annpal.2005.09.003) And in a new book: https://materiologiques.com/en/histoire-des-sciences-et-des-techniques/301-levolution-au-museum-albert-gaudry-9782373612264.html But this does all really rather depend on what a cladogram is, or means. To contrast Muller (1864), Mivart (1865) and Gaudry (1866) might be a worthwhile exercise. But method to one side, if anything branches, isn’t it a cladogram? We did not do that contrast but a peek in this might add to the tale (or confusion): https://www.cambridge.org/core/books/cladistics/D3C3FC2E69F52FB3BDBDBA219157E625