Pyramiding in Tortoises
​Outline
A hot topic for keepers
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We receive a disproportionate amount of questions regarding carapace scute pyramiding. As of current practices and denotations, this is now classified as a Growth-Rate Disease or Growth-Rate Disorder which is irreversible once it actually occurs.​​​​
What is it?
Tortoise shell pyramiding is a condition which effects the growth of the carapace (the top of the tortoise shell) over a period of time. Each individual scute will grow upward, creating a pyramid-like bumpy appearance. Each individual tortoise will have a different degree of pyramiding, from slight to extreme.
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Overall this phenomenon is believed to be a sign of an imbalance of care. It should be noted mild pyramiding can occur naturally and in wild animals. For the purpose of this outline, we will mainly be focusing on the more extreme cases.
Why is it bad?
The widespread consensus is these growth-rate disorders can affect many parts of the tortoise’s quality of life. In more extreme cases, it is extremely debilitating to the animal that develops this. Extreme Pyramiding is defined as a drastic and dramatic pyramid forming on the tortoises scutes to the point of creating valleys on the base carapace.
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It cannot be directly measured. A yearling might have extreme pyramiding (while overall relatively small) of 1-cm deep valleys. In comparison, an adult with a 1-cm deep valley would be classified as mild. The main point is it has to affect the base body of the animal.
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When it begins to deform the base carapace, it will deform the entire exoskeleton of the tortoise. Animals with extreme pyramiding have been documented and x-rayed. The findings showed the entire spine will curve around each pyramid spike, the rib cage will twist and become malformed, and the overall skeletal structure is twisted.
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This can cause pain, mobility issues, poor breathing and even a shortened life spans.​​
Current ideology on Causes for Pyramiding
Scientifically, pyramiding has been hypothesized as coming from Diet, Excess Supplemental Heat, and Humidity.
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Remember, scientifically recognized answers remain unclarified as of 2025, but numerous theories and hypothesis remain valid as a causation. These are the main school of thoughts below.
Diet
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Low fiber / rich in starch diets are linked to one of the main reasons for rapid growth of the carapace. This accelerated growth will cause imbalances in bone mineralization which present in animals with a lower overall bone mass and bone density.
Excess Supplemental Heating
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In 2015 a study spanned over 2-years with a total of 130 captive hatched tortoises consisting of Leopards and Sulcatas. These animals were divided into 2 even groups. These animals in both groups were raised in otherwise similar environmental conditions, offered similar diet, and similar humidity levels. The only factor changed was the excess supplemental nocturnal heat.
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What they discovered over this 2-year cycle is nighttime heat supplied to one group lead to a faster growth rate and a higher likelihood of developing Pyramiding. The most important take-away is the importance of heat cycles.
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Having one singular temperature 24/7 is not great for the animal. Nighttime cooling is needed for their bodies to recover from the day, repair cells and absorb nutrition. This also replicates natural environments. Although Sulcatas and Leopards do not brumate and cannot take extreme cold near freezing, these will cool off slightly to an ambient temperature.
Humidity
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Recognized and popularized as one of the main factors, this theory has been prevalent for years. In general, the levels and susceptibility to different humidity percentages is also dependent on the species in question. You would not compare a Sulcatas humidity levels to a Red Foot Tortoises humidity levels.
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As the general consensus, and widely studied since the early 2000’s, higher humidity has been linked to lower chances of developing Pyramiding. Lower humidity is more likely to produce pyramided animals.
​Sources
Hatt, J.-M. (2008). Raising giant tortoises (M. E. Fowler & R. E. Miller, Eds.; pp. 144–153). Saunders Elsevier.
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Hatt, J., Ritz J., Clauss M., Streich W., (2012). Variation in Growth and Potentially Associated Health Status in Hermann's
and Spur-Thighed Tortoise pp. 705 - 717. Zoo Biology.
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Heinrich M., (2016). Effect of Supplemental Heat in Captive African Leopard Tortoises and Spurred Tortoises on Growth
Rate and Carapacial Scute Pyramiding., pp 18 - 25. The Journal of Exotic Pet Medicine.
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Mendoza P., Futura C., (2022). Starch and Fiber Intake Effects on Metabolism, Growth, and Carapacial Scute Pyramiding of
Red-Foot Tortoise Hatchlings., Comparative Biochemistry and Physiology part A.