So, how well do phylogenetic trees from morphological studies match the trees made from independent molecular studies? There are over 1038 different possible ways to arrange the 30 major taxa represented in
Figure 1 into a phylogenetic tree (see
Table 1.3.1;
Felsenstein 1982;
Li 1997, p. 102). In spite of these odds, the relationships given in Figure 1, as determined from morphological characters, are completely congruent with the relationships determined independently from cytochrome
c molecular studies (for consensus phylogenies from pre-molecular studies see
Carter 1954, Figure 1, p. 13;
Dodson 1960, Figures 43, p. 125, and Figure 50, p. 150;
Osborn 1918, Figure 42, p. 161;
Haeckel 1898, p. 55;
Gregory 1951, Fig. opposite title page; for phylogenies from the early cytochrome
c studies see
McLaughlin and Dayhoff 1973;
Dickerson and Timkovich 1975, pp. 438-439). Speaking quantitatively, independent morphological and molecular measurements such as these have determined the standard phylogenetic tree, as shown in
Figure 1, to better than 38 decimal places. This phenomenal corroboration of universal common descent is referred to as the "twin nested hierarchy". This term is something of a misnomer, however, since there are in reality multiple nested hierarchies, independently determined from many sources of data.