Spurred Tortoise - SS

The African Spurred Tortoise (Centrochelys sulcata) is the third largest tortoise in the world and the largest mainland tortoise. It inhabits the southern edge of the Sahara desert, in northern Africa. As an ectotherm, it must regulate its body temperature using external sources.

Anatomical Adaptations

 * Loose skin increases SA/V ratio, allowing more heat to be radiated away
 * The surface of the carapace acts as a buffer against solar radiation
 * Enlarged bladder to store urine for emergency thermoregulation
 * Strong claws for digging burrows

Physiological Adaptations

 * Rate of respiration depends on body temperature. As body temperature increases, rate of respiration decreases
 * Core body temperature maintained by copious salivation which wets the head, neck and front legs. Latent heat vaporizes, resulting in the cooling effect that sweating has in endotherms
 * Moistening of eyes and urinating

Behavioural Adaptations

 * Burrowing allows body temperature to be reduced - permitting a longer surface activity period in the face of rising ambient temperature
 * Burrows during hottest time of day - also allowing the tortoise to get to areas with higher moisture levels
 * Panting - this is slower in larger tortoises



Rain Season

 * Between July and October, these tortoises will spend the mornings basking in the hot sun in order to raise their body temperatures, so as to endure the cold nights.
 * Hold their breaths for longer periods - a mechanism that could serve to reduce respiratory water loss
 * They are most active at this time of year, particularly at dawn and dusk when they will forage for food