The Baviaanskloof - representative of the Eastern Cape's diverse habitats.

The Baviaanskloof - representative of the Eastern Cape's diverse habitats.


Honours projects 2014

Both these projects are currently on offer in the Department of Zoology, Nelson Metropolitan University. Please contact me for further details: Ben Smit

1. Role of hydration state in thermoregulation: does a higher body temperature contribute to water savings in heat stressed birds?

Evaporative cooling is the most effective physiological pathway of heat loss in birds. However, evaporative cooling is expensive in terms of water requirements and is feasible only if a bird is adequately hydrated. Previous studies have proposed that birds will elevate their body temperature to promote heat dissipation through non-evaporative pathways. By reducing the demands for evaporative cooling this mechanism may contribute greatly to water savings in environments where water is scarce. This project will test the relationship between hydration state, evaporative water loss and body temperature regulation in heat-acclimated, arid-zone birds, e.g. Namaqua Doves (Oena capensis).

2. Does unpredictable food supply affect torpor use in an arid-zone Elephant-Shrew?

Despite many studies reporting heterothermy in endotherms (birds and mammals) very few of these explicitly test predictions on the adaptive value of heterothermy. By reducing body temperature when faced with low and/or unpredictable food availability, animals could reduce their energy demand and increase survival and fitness in unpredictable desert environments. This study will test the effect of different food supply regimes on the torpor patterns and body condition of the Karoo Round-Eared Elephant-Shrew (Macroscelides proboscideus).

MSc Projects 2014

1. Trade-offs in thermal acclimation

This project will be designed to test various trade-offs associated with thermal acclimation in a bird or mammal model species, and investigate the adaptive value of thermal acclimation under different climate regimes.

Brief overview:
Acute heat or cold stress is likely to lower animal performance. However, many studies have shown that if the exposure to one extreme (for example cold) is longer term acclimation responses can increase performance at that extreme. In contrast, acclimation to one end of temperature extremes  (e.g. cold) often compromises performance at the other extreme temperature (James 2013). Acclimation responses could thus easily be maladaptive over short time scales, especially in highly unpredictable heterogeneous environments.  High acclimation responses should be most prevalent in environments where seasonal variation in temperature exceeds daily variation, i.e. seasonal changes in temperature are marked and predictable. However, where daily variation in temperature is large, acclimation responses are expected to be low since the noise in day-to-day variation will mask cues in seasonal temperature variation (James 2013). Although many studies have shown that birds and mammals show temporal and spatial variation responses in thermal acclimation, very few have investigated the potential costs of thermal acclimation.

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