From a paper by Matthew, W. D., Granger, W.,and
Stein, W. 1917.
Once in the not too recent past we discussed what is basically a giant terror turkey of the northern hemisphere. Discovered in Europe and described under the name Gastornis by Hebert at the same time (a pair of decades later) as it was discovered in North America and described as Diatryma by E. D. Cope and Barornis by O. C. Marsh. Diatryma and Barornis, being named 21 and 49 years after Gastornis respectively, have fallen to the level of junior synonym. However, regardless of the level at which these particular species may reside in hierarchical taxonomy, the discovery of multiple members of the genus on multiple continents is of great importance to understanding how "in charge" birds were in the early Cenozoic. Enormous birds were clearly the apex predators of South America, and likely much of Australasia as well with potential large predatory birds spreading to Africa as well. Gastornis is known only from Europe, Asia, and North America, but the fact that apex predators in northern and southern hemispheres both were avian is astounding. Gastornis consists of 3 - 4 species from Europe (G. parisiensis Hébert, 1855;G. sarasini Schaub, 1929;G. geiselensis Fischer, 1978; and G. russeli Martin 1992), a minimally known Chinese species (G. xichuanensis Hou, 1980), and the extremely (comparatively) well known North American species (G. gigantea Cope, 1876).