Department of Physics, Chemistry and Biology (IFM)

Although the Bolivian, highland, Nothoprocta ornata lives in a chronic hypoxic environment it has a small heart relative to its body size, indicating a reduced ability in deliver oxygenated blood to tissues and organs. They are considered to be primitive birds since they are closely related to the ratites, e.g., the ostriches. Even though it is not fully known their primitivity can be a reason for them to have conserved a small heart while living under chronic hypoxic conditions. Having a small heart suggests that N. ornata had to develop physiological adaptive mechanisms involved in the cardiorespiratory system, to ensure a sufficient distribution of oxygen to the tissues. This is crucial during strenuous locomotion, e.g., when escaping a predator. A small heart also implies a reduced ability in transporting oxygenated blood to the tissues, in comparison to the ability of a larger heart, not only because of the small heart size, resulting in a decreased cardiac output but also, due to the fact that N.ornata is living in a chronic hypoxic environment. Furthermore, this finding suggests a lower capability of performing strenuous daily activities, e.g., flying or running, than an animal with a larger heart.

The aim of this study was to investigate the physiological effects on the cardiovascular and respiratory system by monitoring heart rate and ventilation frequency, in the Bolivian, highland living, Tinamou during resting at two different temperatures 4°C and 25°C and during running. The obtained results were later compared with results from chicken (Gallus gallus).