ⓘ Ernst Mayr

                                     

ⓘ Ernst Mayr

Not to be confused with Ernst Mayr computer scientist, Ernst Mayer, Ernst Meyer, Ernest Mayer or Ernest May.

Ernst Walter Mayr was one of the 20th centurys leading evolutionary biologists. He was also a renowned taxonomist, tropical explorer, ornithologist, philosopher of biology, and historian of science. His work contributed to the conceptual revolution that led to the modern evolutionary synthesis of Mendelian genetics, systematics, and Darwinian evolution, and to the development of the biological species concept.

Although Charles Darwin and others posited that multiple species could evolve from a single common ancestor, the mechanism by which this occurred was not understood, creating the species problem. Ernst Mayr approached the problem with a new definition for species. In his book Systematics and the Origin of Species 1942 he wrote that a species is not just a group of morphologically similar individuals, but a group that can breed only among themselves, excluding all others. When populations within a species become isolated by geography, feeding strategy, mate choice, or other means, they may start to differ from other populations through genetic drift and natural selection, and over time may evolve into new species. The most significant and rapid genetic reorganization occurs in extremely small populations that have been isolated as on islands.

His theory of peripatric speciation a more precise form of allopatric speciation which he advanced, based on his work on birds, is still considered a leading mode of speciation, and was the theoretical underpinning for the theory of punctuated equilibrium, proposed by Niles Eldredge and Stephen Jay Gould. Mayr is sometimes credited with inventing modern philosophy of biology, particularly the part related to evolutionary biology, which he distinguished from physics due to its introduction of natural history into science.

                                     

1. Biography

Mayr was the second son of Helene Pusinelli and Dr. Otto Mayr. His father was a jurist District Prosecuting Attorney at Wurzburg but took an interest in natural history and took the children out on field trips. He learnt all the local birds in Wurzburg from his elder brother Otto. He also had access to a natural history magazine for amateurs, Kosmos. His father died just before he was thirteen. The family then moved to Dresden and he studied at the Staatsgymnasium "Royal Gymnasium" until 1918 in Dresden-Neustadt and completed his high school education there. In April 1922, while still in high school, he joined the newly founded Saxony Ornithologists Association. Here he met Rudolf Zimmermann, who became his ornithological mentor. In February 1923, Mayr passed his high school examination Abitur and his mother rewarded him with a pair of binoculars.

On 23 March 1923 on the lakes of Moritzburg, the Frauenteich, he spotted what he identified as a red-crested pochard. The species had not been seen in Saxony since 1845 and the local club argued about the identity. Raimund Schelcher 1891–1979 of the club then suggested that Mayr visit his classmate Erwin Stresemann on his way to Greifswald, where Mayr was to begin his medical studies. After a tough interrogation, Stresemann accepted and published the sighting as authentic. Stresemann was very impressed and suggested that, between semesters, Mayr could work as a volunteer in the ornithological section of the museum. Mayr wrote about this event, "It was as if someone had given me the key to heaven." He entered the University of Greifswald in 1923 and, according to Mayr himself, "took the medical curriculum to satisfy a family tradition but after only a year, he decided to leave medicine and enrolled at the Faculty of Biological Sciences." Mayr was endlessly interested in ornithology and "chose Greifswald at the Baltic for my studies for no other reason than that. it was situated in the ornithologically most interesting area." Although he ostensibly planned to become a physician, he was "first and foremost an ornithologist." During the first semester break Stresemann gave him a test to identify treecreepers and Mayr was able to identify most of the specimens correctly. Stresemann declared that Mayr "was a born systematist". In 1925, Stresemann suggested that he give up his medical studies, in fact he should leave the faculty of medicine and enrol into the faculty of Biology and then join the Berlin Museum with the prospect of bird-collecting trips to the tropics, on the condition that he completed his doctoral studies in 16 months. Mayr completed his doctorate in ornithology at the University of Berlin under Dr. Carl Zimmer, who was a full professor Ordentlicher Professor, on 24 June 1926 at the age of 21. On 1 July he accepted the position offered to him at the museum for a monthly salary of 330.54 Reichsmark.

At the International Zoological Congress at Budapest in 1927, Mayr was introduced by Stresemann to banker and naturalist Walter Rothschild, who asked him to undertake an expedition to New Guinea on behalf of himself and the American Museum of Natural History in New York. In New Guinea, Mayr collected several thousand bird skins he named 26 new bird species during his lifetime and, in the process also named 38 new orchid species. During his stay in New Guinea, he was invited to accompany the Whitney South Seas Expedition to the Solomon Islands. Also, while in New Guinea, he visited the Lutheran missionaries Otto Thiele and Christian Keyser, in the Finschhafen district; there, while in conversation with his hosts, he uncovered the discrepancies in Hermann Detzners popular book Four Years Among the Cannibals in German Guinea from 1914 to the Truce, in which Detzner claimed to have seen the interior, discovered several species of flora and fauna, while remaining only steps ahead of the Australian patrols sent to capture him.

He returned to Germany in 1930, and in 1931 he accepted a curatorial position at the American Museum of Natural History, where he played the important role of brokering and acquiring the Walter Rothschild collection of bird skins, which was being sold in order to pay off a blackmailer. During his time at the museum he produced numerous publications on bird taxonomy, and in 1942 his first book Systematics and the Origin of Species, which completed the evolutionary synthesis started by Darwin.

After Mayr was appointed at the American Museum of Natural History, he influenced American ornithological research by mentoring young birdwatchers. Mayr was surprised at the differences between American and German birding societies. He noted that the German society was "far more scientific, far more interested in life histories and breeding bird species, as well as in reports on recent literature."

Mayr organized a monthly seminar under the auspices of the Linnean Society of New York. Under the influence of J.A. Allen, Frank Chapman, and Jonathan Dwight, the society concentrated on taxonomy and later became a clearing house for bird banding and sight records.

Mayr encouraged his Linnaean Society seminar participants to take up a specific research project of their own. Under Mayrs influence one of them, Joseph Hickey, went on to write A Guide to Birdwatching 1943. Hickey remembered later, "Mayr was our age and invited on all our field trips. The heckling of this German foreigner was tremendous, but he gave tit for tat, and any modern picture of Dr E. Mayr as a very formal person does not square with my memory of the 1930s. He held his own." A group of eight young birdwatchers from The Bronx later became the Bronx County Bird Club, led by Ludlow Griscom. "Everyone should have a problem" was the way one Bronx County Bird Club member recalled Mayrs refrain.

Mayr said of his own involvement with the local birdwatchers: "In those early years in New York when I was a stranger in a big city, it was the companionship and later friendship which I was offered in the Linnean Society that was the most important thing in my life."

Mayr also greatly influenced the American ornithologist Margaret Morse Nice. Mayr encouraged her to correspond with European ornithologists and helped her in her landmark study on song sparrows. Nice wrote to Joseph Grinnell in 1932, trying to get foreign literature reviewed in the Condor: "Too many American ornithologists have despised the study of the living bird; the magazines and books that deal with the subject abound in careless statements, anthropomorphic interpretations, repetition of ancient errors, and sweeping conclusions from a pitiful array of facts. in Europe the study of the living bird is taken seriously. We could learn a great deal from their writing." Mayr ensured that Nice could publish her two-volume Studies in the Life History of the Song Sparrow. He found her a publisher, and her book was reviewed by Aldo Leopold, Joseph Grinnell, and Jean Delacour. Nice dedicated her book to "My Friend Ernst Mayr."

Mayr joined the faculty of Harvard University in 1953, where he also served as director of the Museum of Comparative Zoology from 1961 to 1970. He retired in 1975 as emeritus professor of zoology, showered with honors. Following his retirement, he went on to publish more than 200 articles, in a variety of journals - more than some reputable scientists publish in their entire careers; 14 of his 25 books were published after he was 65. Even as a centenarian, he continued to write books. On his 100th birthday, he was interviewed by Scientific American magazine. Mayr died on 3 February 2005 in his retirement home in Bedford, Massachusetts after a short illness. His wife, Margarete, died in 1990. He was survived by two daughters, five grandchildren and 10 great-grandchildren.

The awards that Mayr received include the National Medal of Science, the Balzan Prize, the Sarton Medal of the History of Science Society, the International Prize for Biology, the Loye and Alden Miller Research Award, and the Lewis Thomas Prize for Writing about Science. In 1939 he was elected a Corresponding Member of the Royal Australasian Ornithologists Union. He was awarded the 1946 Leidy Award from the Academy of Natural Sciences of Philadelphia. He was awarded the Linnean Society of Londons prestigious Darwin-Wallace Medal in 1958 and the Linnaean Society of New Yorks inaugural Eisenmann Medal in 1983. For his work, Animal Species and Evolution, he was awarded the Daniel Giraud Elliot Medal from the National Academy of Sciences in 1967. Mayr was elected a Foreign Member of the Royal Society ForMemRS in 1988. In 1995 he received the Benjamin Franklin Medal for Distinguished Achievement in the Sciences of the American Philosophical Society. Mayr never won a Nobel Prize, but he noted that there is no prize for evolutionary biology and that Darwin would not have received one, either. In fact, there is no Nobel Prize for biology. Mayr did win a 1999 Crafoord Prize. It honors basic research in fields that do not qualify for Nobel Prizes and is administered by the same organization as the Nobel Prize. In 2001, Mayr received the Golden Plate Award of the American Academy of Achievement.

Mayr was co-author of six global reviews of bird species new to science listed below.

Mayr said he was an atheist in regards to "the idea of a personal God" because "there is nothing that supports

                                     

2. Mayrs ideas

As a traditionally trained biologist, Mayr was often highly critical of early mathematical approaches to evolution such as those of J.B.S. Haldane, famously calling such approaches "beanbag genetics" in 1959. He maintained that factors such as reproductive isolation had to be taken into account. In a similar fashion, Mayr was also quite critical of molecular evolutionary studies such as those of Carl Woese. Current molecular studies in evolution and speciation indicate that although allopatric speciation is the norm, there are numerous cases of sympatric speciation in groups with greater mobility such as birds. The precise mechanisms of sympatric speciation, however, are usually a form of microallopatry enabled by variations in niche occupancy among individuals within a population.

In many of his writings, Mayr rejected reductionism in evolutionary biology, arguing that evolutionary pressures act on the whole organism, not on single genes, and that genes can have different effects depending on the other genes present. He advocated a study of the whole genome rather than of isolated genes only. After articulating the biological species concept in 1942, Mayr played a central role in the species problem debate over what was the best species concept. He staunchly defended the biological species concept against the many definitions of "species" that others proposed.

Mayr was an outspoken defender of the scientific method, and one known to sharply critique science on the edge. As a notable example, in 1995, he criticized the Search for Extra-Terrestrial Intelligence SETI as conducted by fellow Harvard professor Paul Horowitz as being a waste of university and student resources, for its inability to address and answer a scientific question. Over 60 eminent scientists led by Carl Sagan rebutted the criticism.

Mayr rejected the idea of a gene-centered view of evolution and starkly but politely criticized Richard Dawkins ideas:

The funny thing is if in England, you ask a man in the street who the greatest living Darwinian is, he will say Richard Dawkins. And indeed, Dawkins has done a marvelous job of popularizing Darwinism. But Dawkins basic theory of the gene being the object of evolution is totally non-Darwinian. I would not call him the greatest Darwinian.

Mayr insisted that the entire genome should be considered as the target of selection, rather than individual genes:

The idea that a few people have about the gene being the target of selection is completely impractical; a gene is never visible to natural selection, and in the genotype, it is always in the context with other genes, and the interaction with those other genes make a particular gene either more favorable or less favorable. In fact, Dobzhansky, for instance, worked quite a bit on so-called lethal chromosomes which are highly successful in one combination, and lethal in another. Therefore people like Dawkins in England who still think the gene is the target of selection are evidently wrong. In the 30s and 40s, it was widely accepted that genes were the target of selection, because that was the only way they could be made accessible to mathematics, but now we know that it is really the whole genotype of the individual, not the gene. Except for that slight revision, the basic Darwinian theory hasnt changed in the last 50 years.

                                     

2.1. Mayrs ideas Currently recognised taxa named in honour of Ernst Mayr

  • Mayrs forest rail Rallicula mayri Hartert, 1930 - a species of bird found in New Guinea.
  • New Ireland rail Gallirallus ernstmayri † Kirchman & Steadman, 2006 - a relatively large, probably flightless, extinct rail, family Rallidae, known from subfossil remains found on prehistoric archeological sites, in caves on New Ireland, in the Bismarck Archipelago, western Oceania)
  • Bismarck black Myzomela psammelaena ernstmayri Meise, 1929 - a subspecies of bird, a honeyeater, family Meliphagidae, confined to several small islands to the west of the Admiralty Islands, in western Oceania, northeast of New Guinea.
  • Mayrs swiftlet Aerodramus orientalisi Mayr, 1935 - a species of bird found in New Ireland and Guadalcanal.
  • a species of spider - Cebrennus mayri Jager, 2000
  • a genus of pseudoscorpions - Ernstmayria Curcic et al., 2006
  • a species of earwig - Irdex ernstmayri Gunther, 1930
  • Star Mountains worm-eating snake Toxicocalamus ernstmayri OShea, Parker & Kaiser, 2015 - a 1.2 m, rare and secretive, venomous snake from the family Elapidae, believed to feed exclusively of earthworms, particularly the giant earthworms of the Megascolecidae. The etymology reads: The species name ernstmayri is a patronym honoring the German-American ornithologist, systematist, and evolutionary thinker Ernst Mayr 1904–2005. There are several connections linking Ernst Mayr to this new species of Toxicocalamus, which make him, and this snake, the ideal candidates for a patronym. First, Mayr himself visited New Guinea, and during the late 1920s he spent over 2 years conducting fieldwork in an area now part of PNG, as a member of a joint Rothschild–AMNH expedition focusing on birds of paradise, during which he collected many new bird and orchid species. Second, the holotype of T. ernstmayri has been housed in the MCZ collection, mislabeled as Micropechis ikaheka, after having arrived and been accessioned in June 1975, the month and year that Mayr retired. Third, the true identity of this specimen was recognized by one of us MOS during a visit to the MCZ in May 2014, undertaken with the financial support of an Ernst Mayr Travel Grant from Harvard University, awarded to enable examination of the Toxicocalamus holdings at the MCZ and the AMNH, the two U.S. institutions where Mayr worked. Finally, 2015, the publication year of this description, marks the decennial of Mayrs passing at age 100, and naming a New Guinea snake after him seems a suitable tribute.
  • a species of damselfly - Palaiargia ernstmayri Lieftinck, 1972
  • a roundworm - Poikilolaimus ernstmayri Sudhaus & Koch, 2004 - a new species of nematode, family Rhabditidae, associated with termites of the genus Reticulitermes, on Corsica.
  • an assassin bug - Bagauda ernstmayri Kulkarni & Ghate, 2016 - a species of cavernicolous, thread-legged assassin bug, known only from Satara, in the Western Ghats of Maharashtra State, India.
  • Ernst Mayrs water rat Leptomys ernstmayri Rummler, 1932 - a species of rodent, of the family Muridae, from the Foja Mountains of Papua Province, Indonesia, and Central Cordillera, Adelbert Range, and Huon Peninsula of Papua New Guinea.
  • Mayrs honeyeater Ptiloprora mayri Hartert, 1930 - a species of bird found in New Guinea.
  • a species of bird lice - Anaticola ernstmayri Eichler, 1954


                                     

3. Mayrs summary of Darwins theory

Darwins theory of evolution is based on key facts and the inferences drawn from them, which Mayr summarised as follows:

  • Individuals in a population vary significantly from one another fact.
  • A struggle for survival ensues inference.
  • Much of this variation is heritable fact.
  • Every species is fertile enough that if all offspring survived to reproduce, the population would grow fact.
  • This slowly effected process results in populations changing to adapt to their environments, and ultimately, these variations accumulate over time to form new species inference.
  • Individuals less suited to the environment are less likely to survive and less likely to reproduce; individuals more suited to the environment are more likely to survive and more likely to reproduce and leave their heritable traits to future generations, which produces the process of natural selection fact.
  • Resources such as food are limited and are relatively stable over time fact.
  • Despite periodic fluctuations, populations remain roughly the same size fact.

In relation to the publication of Darwins Origins of Species, Erst Mayr identified philosophical implications of evolution:

  • The refutation that the universe has purpose.
  • Population thinking replaces essentialism.
  • The implausibility of creationism.
  • Defeating the justifications for a human-centric world.
  • Materialistic processes explain the impression of design.
  • An evolving world, not a static one.
                                     

4.1. Bibliography Books

  • Mayr, Ernst 1991. One Long Argument. Cambridge: Harvard University Press. ISBN 978-0-674-63906-5.
  • Mayr, Ernst 1988. Toward a New Philosophy of Biology. Cambridge: Harvard University Press. ISBN 978-0-674-89666-6.
  • Mayr, Ernst 2001. What Evolution Is. New York: Basic Books. ISBN 978-0-465-04426-9.
  • Mayr, Ernst 1942. Systematics and the Origin of Species, from the Viewpoint of a Zoologist. Cambridge: Harvard University Press. ISBN 978-0-674-86250-0.
  • Mayr, Ernst 1945. Birds of the Southwest Pacific: A Field Guide to the Birds of the Area Between Samoa, New Caledonia, and Micronesia. New York: Macmillan.
  • Mayr, Ernst 1991. Principles of Systematic Zoology. New York: McGraw-Hill. ISBN 978-0-07-041144-9.
  • Mayr, Ernst 2001. The Birds of Northern Melanesia. Oxford Oxfordshire: Oxford University Press. ISBN 978-0-19-514170-2.
  • Mayr, Ernst 1982. The Growth of Biological Thought. Cambridge Mass.: Belknap P. of Harvard U.P. ISBN 978-0-674-36446-2.
  • Mayr, Ernst. & William B. Provine, eds 1980. The Evolutionary Synthesis: Perspectives on the Unification of Biology, ISBN 0-674-27225-0
  • Mayr, Ernst 1970. Populations, Species, and Evolution. Cambridge: Belknap Press of Harvard University Press. ISBN 978-0-674-69013-4.
  • Mayr, Ernst 1963. Animal Species and Evolution. Cambridge: Belknap Press of Harvard University Press. ISBN 978-0-674-03750-2.
  • Mayr, Ernst 1976. Evolution and the Diversity of Life. Cambridge: Belknap Press of Harvard University Press. ISBN 978-0-674-27105-0.
  • Mayr, Ernst 2004. What Makes Biology Unique?. Cambridge: Cambridge University Press. ISBN 978-0-521-84114-6.
  • Mayr, Ernst 1997. This Is Biology. Cambridge: Belknap Press of Harvard University Press. ISBN 978-0-674-88469-4.
                                     

4.2. Bibliography Global reviews of species new to science

  • Mayr, E. 1957. "New species of birds described from 1941 to 1955". Journal of Ornithology. 98: 22–08. doi:10.1007/BF01677166.
  • Zimmer, J. T.; Mayr, E. 1943. "New Species of Birds Described from 1938 to 1941". The Auk. 60 2: 249–262. doi:10.2307/4079651. JSTOR 4079651.
  • Mayr, E.; Vuilleumier, F. 1983. "New species of birds described from 1966 to 1975". Journal of Ornithology. 124 3: 217. doi:10.1007/BF01640607.
  • Mayr, E. 1971. "New species of birds described from 1956 to 1965". Journal of Ornithology. 112 3: 302–316. doi:10.1007/BF01640689.
  • Vuilleumier, F.; Mayr, E. 1987. "New species of birds described from 1976 to 1980". Journal fur Ornithologie. 128 2: 137. doi:10.1007/BF01661691.
  • Vuilleumier, François; LeCroy, Mary; Mayr, Ernst 1992. "New species of birds described from 1981 to 1990". Bulletin of the British Ornithologists Club. 112A: 26.


                                     

4.3. Bibliography Other notable publications

  • 1985. How biology differs from the physical sciences. In D. J. Depew and B H Weber, eds., Evolution at a Crossroads: The New Biology and the New Philosophy of Science, Cambridge MA: The MIT Press, pp. 43–63.
  • 1964 Introduction, Bibliography and Subject Pages vii–xxviii, 491–513 in On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life, by Charles Darwin. A Facsimile of the First Edition. Harvard University Press.
  • 1953 with E G Linsley and R L Usinger. Methods and Principles of Systematica Zoology. McGraw-Hill, New York.
  • 1951 with Dean Amadon, "A classification of recent birds". American Museum Novitates no. 1496
  • 1940 "Speciation phenomena in birds". American Naturalist 74:249–278
  • 1950 The role of the antennae in the mating behavior of female Drosophila. Evolution 4:149–154
  • 1962 "Accident or design: The paradox of evolution". Pages 1–14 in The Evolution of Living Organisms G W Leeper, Ed Melbourne University Press.
  • 1931 "Birds collected during the Whitney South Sea Expedition. XII Notes on Halcyon chloris and some of its subspecies". American Museum Novitates no 469
  • 2000. Biology in the Twenty-First Century Bioscience 50 Oct. 2000: 895–897.
  • 1954 "Changes in genetic environment and evolution". Pages 157–180 in Evolution as a Process J Huxley, A C Hardy and E B Ford Eds Allen and Unwin. London
  • 1946 "The naturalist in Leidys time and today". Proceedings of the Academy of Natural Sciences of Philadelphia 98:271–276
  • 1947 "Ecological factors in speciation". Evolution 1:263–288
  • 1992. The idea of teleology. Journal of the History of Ideas 53:117–135
  • 1984 Evolution and ethics. Pages 35–46 in Darwin, Mars and Freud: Their influence on Moral Theory A L Caplan and B Jennings, Eds. Plenum Press, New York.
  • 1955 "Karl Jordans contribution to current concepts in systematics and evolution". Transactions of the Royal Entomological Society of London 107:45–66
  • 1996. The autonomy of biology: the position of biology among the sciences. Quarterly Review of Biology 71:97–106
  • 1946 "History of the North American bird fauna" Wilson Bulletin 58:3–41
  • 1935 "Bernard Altum and the territory theory". Proceedings of the Linnaean Society of New York 45, 46:24–38
  • 1929 with W Meise. Zeitschriftenverzeichnis des Museums fur Naturkunde Mitteilungen aus dem Zoologischen Museum in Berlin 14:1–187
  • 2002. with Walter J Bock. Classifications and other ordering systems. Zeitschrift Zool. Syst. Evolut-Forsch. 40:1–25
  • 1948 "The new Sanford Hall". Natural History 57:248–254
  • 1980 with W B Provine, Eds. The Evolutionary Synthesis. Harvard University Press.
  • 1974 Teleological and teleonomic: A new analysis. Boston studies in the Philosophy of Science 14:91–117
  • 1941 "Borders and subdivision of the Polynesian region as based on our knowledge of the distribution of birds". Proceedings of the 6th Pacific Scientific Congress 4:191–195
  • 1988. The why and how of species. Biology and Philosophy 3:431–441
  • 1930 by Ernst Hartert "List of birds collected by Ernst Mayr". Ornithologische Monatsberichte 36:27–128
  • 1956 with C B Rosen. "Geographic variation and hybridization in populations of Bahama snails Cerion". American Museum Novitates no 1806.
  • 1930 "My Dutch New Guinea Expedition". 1928. Ornithologische Monatsberichte 36:20–26
  • 1961 "Cause and effect in biology: Kinds of causes, predictability, and teleology are viewed by a practicing biologist". Science 134:1501–1506
  • 2001. Mayr, E. 2001, "The philosophical foundations of Darwinism" PDF, Proceedings of the American Philosophical Society, 145 4: 488–495, PMID 11894859, archived from the original PDF on 2008-04-14
  • 1959 "Agassiz, Darwin, and Evolution". Harvard Library Bulletin. 13:165–194
  • 1944 "Wallaces Line in the light of recent zoogeographics studies". Quarterly Review of Biology 19:1–14
  • 1981 Evolutionary biology. Pages 147–162 in The Joys of Research W. Shripshire Jr, Ed. Smithsonian Institution Press.
  • 1965 Comments. In Proceedings of the Boston Colloguium for the Philosophy of Science, 1962–1964. Boston Studies in the Philosophy of Science 2:151–156
  • 1951 Introduction and Conclusion. Pages 85.255–258 in The problem of land connections across the South Atlantic with special reference to the Mesozoic. Bulletin of the American Museum of Natural History 99:79–258
  • 1997. The objects of selection Proc. Natl. Acad. Sci. USA 94 March: 2091–94.
  • 1923 "Die Kolbenente Nyroca rufina auf dem Durchzuge in Sachsen". Ornithologische Monatsberichte 31:135–136
  • 1938 Birds of the Crane Pacific expedition, Ernst Mayr and Sidney Camras, Zoological Series of the Field Museum of Natural History, Volume XX, No. 34.
  • 1943 "A journey to the Solomons". Natural History 52:30–37.48
  • 1941 "The origin and history of the bird fauna of Polynesia". Proceedings of the 6th Pacific Scientific Congress 4:197–216
  • 1927 "Die Schneefinken Gattungen Montifringilla und Leucosticte" J. fur Ornithologie 75:596–619
  • 1957 "Species concepts and definitions". Pages 371–388 in The Species Problem E. Mayr ed. AAAS, Washington DC.
  • 1926 "Die Ausbreitung des Girlitz Serinus canaria serinus L. Ein Beitrag zur Tiergeographie". J. fur Ornithologie 74:571–671
  • 1972 Geography and ecology as faunal determinants. Pages 549–561 in Proceedings XVth International Ornithological Congress K H Voous, Ed E J Brill, Leiden, The Netherlands.
  • 1980 How I became a Darwinian, Pages 413–423 in The Evolutionary Synthesis E Mayr and W Provine, Eds Harvard University Press, Cambridge, Massachusetts.
  • 1959 "Darwin and the evolutionary theory in Biology". Pages 1–10 in Evolution and Anthropology: A Centennial Appraisal B J Meggers, Ed The Anthropological Society of Washington, Washington DC.
  • 1932 "A tenderfoot explorer in New Guinea" Natural History 32:83–97
  • 1969 Discussion: Footnotes on the philosophy of biology. Philosophy of Science 36:197–202
  • 1999. Darwins influence on modern thought Crafoord Prize lecture, September 23, 1999.
  • 1994. with W.J. Bock. Provisional classifications v. standard avian sequences: heuristics and communication in ornithology. Ibis 136:12–18
  • 1923 "Der Zwergfliegenschnapper bei Greifswald". Ornithologische Monatsberichte 31:136
  • 1959 "The emergence of evolutionary novelties". Pages 349–380 in The Evolution of Life: Evolution after Darwin, vol 1 S. Tax, ed University of Chicago.
  • 1978 Tenure: A sacred cow? Science 199:1293
  • 1985. Darwins five theories of evolution. In D. Kohn, ed., The Darwinian Heritage, Princeton NJ: Princeton University Press, pp. 755–772.
  • 1931 Die Vogel des Saruwaged und Herzoggebirges NO Neuginea Mitteilungen aus dem Zoologischen Museum in Berlin 17:639–723
  • 1996. What is a species, and what is not? Philosophy of Science 63 June: 262–277.
  • 1944 "Timor and the colonization of Australia by birds". Emu 44:113–130
  • 1972 Continental drift and the history of the Australian bird fauna. Emu 72:26–28
  • 1944 "The birds of Timor and Sumba". Bulletin of the American Museum of Natural History 83:123–194
  • 1972 Lamarck revisited. Journal of the History of Biology. 5:55–94