Enamel hypoplasia provides insights into early systemic stress in wild and captive giraffes (Giraffa camelopardalis)
Publication Type: |
Journal Article |
Year of Publication: |
2004 |
Authors: |
Tamara A. Franz-Odendaal |
Publication/Journal: |
Journal of Zoology |
Keywords: |
captive, enamel hypoplasia, giraffidae, systemic stress |
ISBN: |
0952-8369 1469-7998 |
Abstract:
Enamel hypoplasia, a developmental tooth defect, provides a permanent record of systemic stress during early life.
The incidence and distribution of linear enamel hypoplasia has been used by anthropologists and palaeontologists to
assess the health status of past populations but has not been applied by wildlife biologists studying extant animals.
This study investigates enamel hypoplasia in 23Giraffa camelopardalisskulls from wild and captive animals of
various ages and sex to determine whether any systemic stress events are unique to life in captivity. Results indicate
that wild giraffes are relatively stress-free as they do not have linear defects. Based on the distribution of linear
defects in other giraffes, three key stress periods during the first 6 years of giraffe life were identified. The first
stress event occurs during weaning, the second at about 3 years of age and the third, which is the least common,
at 4–5 years of age. All three stress events were observed in both male and female giraffes. This study highlights
the usefulness of assessing enamel hypoplasia in both wild and captive animals as well as the need for further
research on tooth developmental timings in many wild ungulates. Some left–right asymmetry was observed in the
development of linear and non-linear defects, which has implications for the aetiology of these defects.