Biochemical adaptations to diving in the common murre, Uria aalge, and the Atlantic puffin, Fratercula arctica
Abstract To evaluate whether specialized biochemical adaptations facilitate the extensive breath‐hold capacities of diving alcids, we compared several such parameters in three locomotor muscles of the common murre, Uria aalge , and the Atlantic puffin, Fratercula arctica , with those in the correspo...
| Published in: | Journal of Experimental Zoology |
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| Main Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Wiley
1990
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1002/jez.1402530302 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjez.1402530302 https://onlinelibrary.wiley.com/doi/pdf/10.1002/jez.1402530302 |
| Summary: | Abstract To evaluate whether specialized biochemical adaptations facilitate the extensive breath‐hold capacities of diving alcids, we compared several such parameters in three locomotor muscles of the common murre, Uria aalge , and the Atlantic puffin, Fratercula arctica , with those in the corresponding muscles of two terrestrial species, the pigeon, Columbia livia , and the pheasant, Phasianus colchicus . The pheasant and pigeon were chosen since they provide recognizably different patterns of biochemical support for flight. The pectoral, supracoracoideus and sartorius muscles were examined since they are the major locomotor muscles. The biochemical modifications which distinguish alcid muscles from pigeon muscles are subtle but include greater hexokinase activities in pigeon muscles, greater myoglobin levels in alcid muscles, and differences in the intraspecific ranking of the muscles' capacities for glycolysis from glycogen. By contrast, the capacities for glycolysis from glycogen, the buffering capacities, and the regulatory properties of pyruvate kinase of these muscles are similar in alcids and pigeons. We conclude that diving does not require major modifications of the overall metabolic design of muscle used by a bird which is capable of sustained aerobic flight. On the other hand, the biochemical differences between pheasants and alcids are more pronounced. Pheasant pectoral has a higher capacity for glycolysis from glycogen than any of the other muscles. Flight muscles in pheasants have higher buffering capacities than those in alcids. Clearly the glycolytic specialization of pheasant flight muscles is not shared by alcid flight muscles. Thus, we suggest that alcids do not rely upon glycolysis to any considerable extent during flight or diving. |
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