Moritz Wagner

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Moritz Wagner (October 3, 1813 in Bayreuth - May 31, 1887 in Munich, suicide) was a German traveler, geographer and a natural scientist.

His brother Rudolf was a physiologist and anatomist.

During 1852 - 1855, together with Carl Scherzer, travelled through North and Central America and the Caribbean. He also visited Persia, Georgia and Northern Iraq.

[edit] Wagner's significance

Ernst Mayr, the evolutionist and historian of biology, has given a clear account of Wagner's significance.^[1] Wagner spent three years in Algeria, when (amongst other activities) he studied flightless beetles. Each genus is split into a number of species, each of which is confined to a stretch of the north coast between rivers which descend from the Atlas mountains to the Mediterranean. As soon as one crossed a river, a different but closely related species appeared.^[2]

Wagner was able to confirm these observations in the Caucasus and in the Andean valleys, leading him to conclude:^[3]

"... an incipient species will only [arise] when a few individuals transgress the limiting borders of their range... the formation of a new race will never succeed... without a long continued separation of the colonists from the other members of their species."

There in a nutshell we have it: an early description of the process of geographic speciation. Another formulation of this idea came later: "Organisms which never leave their ancient area of distribution will never change." ^[4] This cannot be literally true, but it is close enough to be memorable.

The fate of this fine idea was unhappy. The most outstanding evolutionists (Darwin, Wallace, Weismann) attacked it and it suffered a long decline until in 1942 it was reintroduced by Mayr.^[5] The importance of geographic speciation became one of the core ideas of the evolutionary synthesis.^[6]

[edit] References

1. ^ Mayr E. 1982. The growth of biological thought: diversity, evolution and inheritance. Harvard. p562 et seq.
2. ^ Wagner M. Reisen in der Regentschaft Algier in den Jahren 1836, 1837 & 1838. Voss, Leipzig. p199-200
3. ^ Wagner M. 1873. The Darwinian theory and the law of the migration of organisms. Translated by I.L. Laird, London.
4. ^ Wagner, M. 1889. Die Entstehung der Arten durch räumliche Sonderung. Schwalbe, Basel. p82
5. ^ Mayr E. 1942. Systematics and the origin of species. Columbia, N.Y.
6. ^ Huxley J.S. 1942. Evolution: the new synthesis. Allen & Unwin, London.

[edit] External links

• Short biography (in German)
• Moritz Wagner, Travels in Persia, Georgia and Koordistan T. 1-3 (Farnborough, 1970) (facsimile reprint of ed. London, 1856).