In 80 domestic chickens from 8 breeds, the volumes of 12 brain parts were identified as dimensions in a cluster analysis. Based on Euclidean metrics and the Ward algorithm at least 2 groups were found that are congruent with the breeds ‘White Crested Polish chicken’ and ‘Breda’, although the breed identity was not a variable used in the cluster analysis. Domestication is interpreted as evolution which includes the possibility of speciation. It is hypothesized that White Crested Polish chickens and Bredas are becoming new species in terms of a biospecies concept.

Keywords:
Birds, Domestication, Intraspecific variability, Speciation, Chicken breeds, Brain allometry, Cluster analysis
1.
Anderson, M. (1994) Sexual Selection. Princeton University Press, Princeton, New Jersey, USA.
2.
Bachmann, K. (1998) Species as units of diversity: an outdated concept. Theory Biosci., 117: 213–230.
3.
Baron, G., H. Stephan, and H. Frahm (1996) Comparative Neurobiology in Chiroptera. Vol. 1. Birkhäuser, Basel.
4.
Bischof, H.J., and A. Rollenhagen (1999) Behavioural and neurophysiological aspects of sexual imprinting in zebra finches. Behav. Brain Res., 98: 267–276.
5.
Clark, D.A., P.P. Mitra, and S.S.-H. Wang (2001) Scalable architecture in mammalian brains. Nature, 411: 189–193.
6.
Corbet, G.B., and J. Clutton-Brock (1984) Taxonomy and nomenclature. In Evolution of Domesticated Animals (ed. by I.L. Mason), Longman, London-New York, pp. 434–438.
7.
Crawford, R.D. (1984) Domestic fowl. In Evolution of Domesticated Animals (ed. by I.L. Mason), Longman, London-New York, pp. 298–311.
8.
Darwin, C.R. (1859) On the Origin of Species by Means of Natural Selection. Murray, London.
9.
Darwin, C.R. (1868) The Variation of Animals and Plants under Domestication. 2 Vol. Murray, London.
10.
De Winter, W., and C.E. Oxnard (2001) Evolutionary radiations and convergences in the structural organization of mammalian brains. Nature, 409: 710–714.
11.
Deacon, T. (1990) Rethinking mammalian brain evolution. Am. Zool., 30: 629–705.
12.
Desforges, M.F., and D.G.M. Wood-Gush (1976) Behavioural comparison of Aylesbury and Mallard ducks: sexual behaviour. Animal Behaviour, 24: 391–397.
13.
Dobzhansky, T. (1937) Genetics and the Origin of Species. Columbia University Press, New York.
14.
Dubois, E. (1914) Die gesetzmässige Beziehung von Gehirnmasse zu Körpergrösse bei den Wirbeltieren. Z. Morph. Anthrop., 18: 323–350.
15.
Engelmann, C. (1975) Vererbungsgrundlagen und Zuchtmethoden beim Geflügel. Neumann, Leipzig (Germany).
16.
Finlay, B.L., and R.B. Darlington (1995) Linked regularities in the development and evolution of mammalian brains. Science, 268: 1578–1584.
17.
Finlay, B.L., R.B. Darlington, and N. Nicastro (2001) Developmental structure in brain evolution. Behav. Brain Sci., 24: 263–308.
18.
Fisher, R.A. (1930) The Genetical Theory of Natural Selection. Facsimile Reprint 1999, Oxford University Press, Oxford, UK.
19.
Frahm, H.D. and G. Rehkämper (1998) Allometric comparison of the brain and brain structures in the White Crested Polish chicken with uncrested domestic chicken breeds. Brain Behav. Evol., 52: 292–307.
20.
Frahm, H., G. Rehkämper, and C. Werner (2001) Brain alteration in a crested versus non-crested breeds of domestic ducks (Anas platyrhynchos f.d.). Poultry Sci., 80: 1249–1257.
21.
Gallyas, F. (1971) A principle for silver staining of tissue elements by physical development. Acta Morphol. Acad. Sci. Hung., 19: 57–71.
22.
Hammerstein, P. (1998) What is evolutionary game theory?. In Game Theory and Animal Behavior (ed. by L.L. Dugatkin, and H.K. Reeve), Oxford University Press, Oxford, UK, pp. 3–15.
23.
Harvey, P.H., and J.R. Krebs (1990) Comparing brains. Science, 249: 140–146.
24.
Hemmer, H. (1990) Domestication: the Decline of Environmental Appreciation. Cambridge University Press, Cambridge, UK.
25.
Herre, W., and M. Röhrs (1990) Haustiere – zoologisch gesehen. Fischer, Stuttgart (Germany).
26.
Hoy, R.R. (1990) Evolutionary innovation in behavior and speciation: opportunities for behavioral neuroethology. Brain Behav. Evol., 36: 141–153.
27.
Iwaniuk, A.N., and J.E. Nelson (2001) A comparative analysis of relative brain size in waterfowl (Anseriformes). Brain Behav. Evol., 57: 87–97.
28.
Jerison, H. (1994) Evolution of the brain. In Neuropsychology. Handbook of Perception and Cognition (ed. by D.W. Zaidel), Academic Press, San Diego, CA, pp. 53–82.
29.
Kruska, D. (1988) Mammalian domestication and its effect on brain structure and behavior. In Intelligence and Evolutionary Biology (ed. by H. Jersion and I. Jerison), NATO ASI Series, Vol. G17. Springer, Berlin (Germany), pp. 211–250.
30.
Lapicque, L. (1907) Tableau général des poids somatique et encephalique dans les espèces animal. Bull. Soc. Anthrop. Paris 5e serie, Vol. 8.
31.
Lapointe, F.-J., G. Baron, and P. Legendre (1999) Encephalization, adaptation and evolution of chiroptera: a statistical analysis with further evidence for bat monophyly. Brain Behav. Evol., 54: 119–126.
32.
Lefebvre, L., P. Whittle, E. Lascaris, and A. Finkelstein (1997) Feeding innovations and forebrain size in birds. Anim. Behav., 53: 549–560.
33.
Lefebvre, L., N. Juretic, N. Nicolakakis, and S. Timmermans (2001) Is the link between forebrain size and feeding innovations caused by confounding variables? A study of Australian and North American birds. Anim. Cog., 4: 91–97.
34.
Lill, A., and D.G.M. Wood-Gush (1965) Potential ethological isolating mechanisms in assortative mating in the domestic fowl. Behaviour, 25:16–44.
35.
Lockard, R.B. (1968) The albino rat: a defensible choice or a bad habit. Am. Psychol., 23: 734–742.
36.
Magurran, A.E. (1999) Population differentiation without speciation. In Evolution of Biological Diversity (ed. by A.E. Magurran and R.M. May), Oxford University Press, Oxford, UK, pp. 160–183.
37.
Maynard Smith, J. (1958) The Theory of Evolution. Penguin Books, Harmondsworth, UK.
38.
Mayr, E. (1963) Animal Species and Evolution. The Belknap Press of Harvard University Press, Cambridge, MA.
39.
Mayr, E. (1970) Population, Species, and Evolution. An Abridgement of Animal Species and Evolution. The Belknap Press of Harvard University Press, Cambridge, MA.
40.
Merker, B. (1983) Silver staining of cell bodies by means of physical development. J. Neurosci. Meth., 9: 235–241.
41.
Moeller, H. (1975) Zur Grössenabhängigkeit von Hirnmerkmalen beim Hauskaninchen. Zool. Jb. Anat., 94: 161–199.
42.
Price, E.O. (1998) Behavioral genetics and the process of domestication. In Genetics and the Behavior of Domestic Animals (ed. by T. Grandin), Academic Press, San Diego, CA, pp. 31–65.
43.
Price, E.O. (1999) Behavioral development in animals undergoing domestication. Appl. Anim. Behav. Sci., 65: 245–271.
44.
Regenstein, F. (1970) Vererbung bei Hühnern und Tauben. Oertel und Spörer, Reutlingen (Germany).
45.
Rehkämper, G., H.D. Frahm, and M. Dion (1999) Eye muscle nuclear size in a breed of domestic rabbits with floppy ears. J. Brain Res., 39: 401–408.
46.
Rehkämper, G., H.D. Frahm, and K. Zilles (1991) Quantitative development of brain structures in birds (Galliformes and Passeriformes) compared to that in mammals (Insectivores and Primates). Brain Behav. Evol., 37: 125–143.
47.
Rehkämper, G., E. Haase, and H.D. Frahm (1988) Allometric comparison of brain weight and brain structure volumes in different breeds of domestic pigeons, Columba livia f.d. (Fantails, Homing pigeons, Strassers) Brain Behav. Evol., 31: 141–149.
48.
Requate, H. (1959) Federhauben bei Vögeln. Eine genetische und entwicklungsphysiologische Studie zum Problem der Parallelbildungen. Z. Wiss. Zool., 162: 191–313.
49.
Röhrs, M. (1959) Neue Ergebnisse und Probleme der Allometrieforschung. Z. Wiss. Zool., 162:1–95.
50.
Romanov, M.N., and S. Weigend (2001) Analysis of genetic relationship between various populations of domestic and jungle fowl using microsatellite markers. Poultry Sci. 80: 1057–1063.
51.
Romeis, B. (1989) Mikroskopische Technik. Urban und Schwarzenberg, München (Germany).
52.
Snell, O. (1892): Die Abhängigkeit des Hirngewichts von dem Körpergewicht und den geistigen Fähigkeiten. Arch. Psych. Nervenkr., 23: 436–446.
53.
Spurway, H. (1955) The causes of domestication: An attempt to integrade some ideas of Konrad Lorenz with evolution. J. Genetics, 53: 325–362.
54.
Stephan, H., G. Baron, G., H.D. Frahm, and M. Stephan (1986) Grössenvergleiche an Gehirnen und Hirnstrukturen von Säugern. Z. mikrosk. anatom. Forsch., 100: 189–212.
55.
Tierney, A.J. (1996) Evolutionary implications of neural circuit structure and function. Behav. Proc., 35: 173–182.
56.
Timmermans, S., L. Lefebvre, D. Boire, and P. Basu (2000) Relative size of the hyperstriatum ventrale is the best predictor of feeding innovation rate in birds. Brain Behav. Evol., 56: 196–203.
57.
Tinbergen, N. (1952) The Study of Instinct. Oxford University Press, London, UK.
58.
Tinbergen, N. (1953) The Herring Gull’s World. (revised 1961). Collins, London, UK.
59.
Wagner, H.-J. (2001) Sensory brain areas in mesopelagic fishes. Brain Behav. Evol., 57: 117–133.
60.
Wood-Gush, D.G.M. (1959) A history of the domestic chicken from antiquity to the 19th century. Poultry Sci., 38: 321–326.
61.
Wree, A. (1986) Reduktion der Plastizität des visuellen Systems in der postnatalen Ontogenese der Ratte. Habilitationsschrift, Universität Köln, Germany.
62.
Zeuner, F. (1963) A History of Domesticated Animals. Hutchinson, London, UK.
63.
Zilles, K., A. Schleicher, and F. Pehlemann (1982) How many sections must be measured in order to reconstruct the volume of a structure using serial sections? Microscop. Acta, 86: 339–346.
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