Eutaxia

Under Eutaxie means the complete ranking of the secondaries of a bird's wing.

In this case, gapless means that the transversal rows, which are composed of flight feathers and a set of associated upper and lower cover feathers, are complete. If a transverse row without an arm swing is inserted between the arm wings 4 and 5, one speaks of diastataxia .

The eutaxic fletching of the wing is the normal case. When the wing is folded up, the flight feathers including the cover springs are pushed over one another. Because of the sometimes required more wing folding in some groups of birds, the diastataxic gap developed for relief . This results from the insertion of an additional transverse row without the associated flywheel.

This concerns the passerine birds (Passeriformes), the woodpeckers (Piciformes) and the cuckoos (Cuculiformes) completely. Among the hen birds (Galliformes), the waders (Charadriiformes) and the pigeons (Columbiformes) there are species with both eutaxic and diastataxic fletching.

literature

• Wolf-Dieter Busching: Handbook of the plumage of European birds. AULA-Verlag, Wiesbaden 1997, ISBN 3-89104-570-0 .