Veranderungen von Hirn‐ und Augengröißen bei wilden und domestizierten Truthühnern (Meleagris gallopavo L., 1758)1

Reductions of brain and eye weight in the wild and domestic turkey (Meleagris gallopavo) Studied is the intraspecific relationship between brain and eye weight to total body weight in native turkes and domestic strains. Brain. The turkeys show a common allometric exponent of a = 0.25. Differences in sex are found only within wild turkeys; gobbler and hen differ by 17.9 %. A reduction in brain weight of 35.2 % between wild male and domestic turkeys and of 23.8 % between wild hen and domestic turkeys are observed. Eyes. Differences in sex within each class independent from body size are not found. But there exist considerable reductions in eye weight from wild to domestic state. In wild turkeys eye weight is by 26.9 % heavier than in domestic strains. Changes in brain size are compared with observations found in other fowls. The two heritable complexes wildness and domesticity are discussed with evolutional, functional and environmental connexions.