News Archive

By Mark Foreman

Science Communications student

Shane Maloney's study of animal thermoregulation has inadvertently thrown him into the vast scientific field of global warming.

Professor Maloney, in the School of Anatomy, Physiology and Human Biology, studies the temperature of animals: why it rises and falls, how animals adapt to heat and cold, and more recently, how they cope with a changing climate.

His work has taken him all over the world, including one of the hottest and driest regions in the world, the Arabian Desert, to study the oryx.

A distant relative of the camel, the oryx has adapted to one of the harshest climates in the world very successfully.

"Physiologists love extremes, and the oryx lives in one of the absolute extremes, where they go for months without drinking water," Professor Maloney explained.

The team implanted five oryx with data loggers and monitored their core temperature for a year. The question they wanted answered was: Does water limitation drive heterothermy? Heterothermy is the fluctuation of body temperature beyond the normal limits of that animal.

They found that during the hot-dry months, the amplitude of core temperature was greater than during the hot-wet months. Similarly, a greater amplitude was recorded during the cool-dry months compared to the cool-wet months. The pattern seemed to be clear, a lack of water was causing higher maximums and lower minimums.

The research showed that given access to drinking water, the oryx remained homeothermic, that is, they kept their fluctuations of body temperature within normal levels. When water wasn't available there was a distinct activation of heterothermy. This evidence enabled the team to refute the existing claim that external temperature alone was the biggest inducer of heterothermy.

By inducing heterothermy, the oryx stored heat rather than using water to remove heat from the body (via sweating and panting). This water conservation is paramount to the animals' survival.

Studies such as this provide information as to how animals might cope with further temperature increase. "The oryx is doing OK," Professor Maloney said. "But nobody can be sure how they will fare in the long run."

To go more than 100 days without drinking water, as the oryx can, holds it in good stead to tackle the challenge of global warming. "This is a remarkable adaptation, and perhaps they do have the capacity to adapt enough to see the survival of the species," he said. "Global warming is moving in quickly though. There may not be enough time."

Published in UWA News , 23 July 2012