Geography Reference
In-Depth Information
U.S. ornithologist Ernst Mayr (1904-2005), one of the most influential
authors in evolutionary biology, played a key role in the Modern Evolutionary
Synthesis, the unified theory of evolution developed in the 1940s. Although
his biogeographic ideas share many similarities with those of the authors
belonging to the New York school of zoogeography, they do not derive from
Matthew but rather from Erwin Stresemann (1889-1972), a disciple of Ger-
man ornithologist Otto Kleinschmidt (1870-1954). In fact, it is interesting to
notethatthebiogeographicideasofMayr,Croizat,andHennigmightalllead
back to Kleinschmidt (Williams 2007b).
In
Systematics and the Origin of Species,
Mayr (1942:155) analyzed in
detail the process of geographic speciation: “A new species develops if a
population which has become geographically isolated from its parental spe-
cies acquires during this period of isolation characters which promote or
guarantee reproductive isolation when the external barriers break down.”
Mayr considered this “geographic speciation” to be the orthodox theory
and disregarded the possibility of sympatric speciation. In order to detail the
an ancestral species is differentiated into subspecies and the geographic
barriers develop and isolate the subspecies, which by later range expansion
establish a hybrid zone between the new species. The general approach fol-
lowed by Mayr is the historical dynamic method, which stressed the need to
examine entire faunas, analyzing the dispersal capabilities and distributional
ranges of the species as well as the ecological and geological history of the
area analyzed in order to understand the biogeographic history as a dynam-
ic and continuing process (Haffer et al. 2000). Mayr argued that knowledge
of biogeography may offer critical insight into evolution; however, he did not
include it in the four disciplines dealing with evolution—systematics, genet-
ics, paleontology, and ecology—when founding the Society for the Study of
Evolution in 1945 (Cain 1993).
