Temperature regulation in the echidna (Tachyglossus aculeatus)

✍ Scribed by Knut Schmidt-Nielsen; T. J. Dawson; E. C. Crawford

• Publisher: John Wiley and Sons
• Year: 1966
• Tongue: English
• Weight: 755 KB
• Volume: 67
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1040670108

✦ Synopsis

The echidna (Tachyglossus aculeatus) maintained a body temperature of 30.7"C f 1.03 s.d. ( N = 23) at ambient temperatures (TA) between 0 and 25°C.

It may, however, also become hypothermic at low TA. At T*=3O0C or above the echidna became hyperthermic. The thermoneutral range was about 20-30°C. At low TA the metabolic rate might be increased several fold. The thermal conductance was at a minimum at TA = 20"C, and was not further reduced at lower TA. At higher TA the thermal conductance increased up to five-fold. The evaporation showed little change with increasing TA. At the highest TA we used (33°C) the evaporation on the average accounted for the dissipation of only about one-third of the metabolic heat produced. These findings suggest that the echidna, although it can maintain its body temperature at low ambient temperature, cannot rely upon evaporation as the major avenue for heat loss at high ambient temperature.