Embryonic development and functional readiness of the sound-transmitting system of acoustic analyzer in Larus gulls
Autor: | L. I. Barsova, V. D. Anisimov |
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Rok vydání: | 2012 |
Předmět: |
geography
geography.geographical_feature_category biology Embryogenesis Anatomy biology.organism_classification General Biochemistry Genetics and Molecular Biology Incubation period Pulmonary respiration medicine.anatomical_structure otorhinolaryngologic diseases Outer ear medicine Middle ear Inner ear sense organs General Agricultural and Biological Sciences Larus Sound (geography) |
Zdroj: | Biology Bulletin. 39:593-600 |
ISSN: | 1608-3059 1062-3590 |
Popis: | Morphometric parameters of the developing sound-transmitting system of the peripheral acoustic analyzer have been studied in embryos of the common gull (Larus canus) and black-headed gull (L. ridibundus) beginning from the second half of the incubation period. The results show that structures of the outer ear and the middle-ear columellar complex at the stage corresponding to 77–79% of the incubation period have not yet completed morphogenesis and cannot perform their functions. At subsequent stages, morphometric characteristics of the columellar complex allow it to participate in sound transmission, but only in the air, while the embryos are still submerged in the amniotic fluid. Beginning from days 23–24 (88–92% of the incubation period) in L. canus and days 21–22 (87–91%) in L. ridibundus, the embryos perforate the shell membrane, start pulmonary respiration, and develop acoustic signaling. Since that time, the outer and middle ear become involved in continuous transmission of acoustic signal to the inner ear receptors. |
Databáze: | OpenAIRE |
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