A Practical Criticism of Hennig-Brundin "Phylogentic Systematics" and Antarctic Biogeography

• Published in: Systematic Biology
• Main Author: Darlington, P. J.
• Format: Text
• Language: English
• Published: Oxford University Press 1970
• Subjects: Articles; Antarctic; Antarc*; Antarctica
• Online Access: http://sysbio.oxfordjournals.org/cgi/content/short/19/1/1; https://doi.org/10.1093/sysbio/19.1.1

A practical criticism of Hennig-Brundin “Phylogenetic Systematics” and Antarctic biogeography. Syst. Zool., 19:1–18 .—Hennig's (1966) Phylogenetic Systematics is primarily concerned with cladism. The central thesis is that all taxa must be monophyletic in a special, rigid sense, and that their rank must be determined solely by time of origin. Secondary concepts are that species split in a very simple way; that one of two daughter species derived from a common ancestor will deviate more than the other; that species divide only dichotomously and that phylogenies must be dichotomous; that rates of evolution and divergence are constant and the same in different groups, unless known to be different; that relative primitiveness established at time of species-splitting remains characteristic of groups throughout their history; and that primitive groups remain at or near their places of origin. These concepts are all oversimplified, in part illogical, not consistent with real situations that are common in nature, and of no practical use in systematics or biogeography. Brundin (1966) accepts and further oversimplifies Hennig's concepts and applies them uncritically in classification of southern chironomid midges and antarctic biogeography. His supposed history of antarctic land connections, beginning in the Jurassic, is based on application of Hennig's erroneous secondary concepts, on an imaginary parallelism between chironomids and birds, and on an arbitrary decision that chironomids cannot cross water gaps although they occur in aereal plankton. His conclusions are probably wrong as to dating, as to directions of dispersal, and as to existence of continuous land connections. Existing chironomids may really have dispersed during or not long before the Tertiary, along the edges of Antarctica, and across water gaps between the southern tips of the continents and Antarctica.