Hypoxia adaptation in fish of the Amazon: a never-ending task

摘要: In addition to seasonal long-term changes in dissolved oxygen and carbon dioxide, water bodies of the Amazon present periodic short-term episodes hypoxia even anoxia. To preserve gas exchange acid base balance, fish have developed multiple adaptive solutions which occur at all biological levels. These are thought represent convergence rather than phylogenetic relatedness. Fish exposed different experimental conditions adjust, for example, several parameters improve transfer from gas-exchange site tissues. include morphological such as development lower lip Colossoma, ventilation rates, circulatory parameters, increased circulating red blood cells, decreased levels intraerythrocytic phosphates, adjustments pH (pHi). that allow survive both short- degrees fi...