Myth, Marula, and Elephant: An Assessment of Voluntary Ethanol Intoxication of the African Elephant ( Loxodonta africana ) Following Feeding on the Fruit of the Marula Tree ( Sclerocarya birrea )

School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, United Kingdom.
Physiological and Biochemical Zoology (Impact Factor: 2.4). 03/2006; 79(2):363-9. DOI: 10.1086/499983
Source: PubMed


Africa can stir wild and fanciful notions in the casual visitor; one of these is the tale of inebriated wild elephants. The suggestion that the African elephant (Loxodonta africana) becomes intoxicated from eating the fruit of the marula tree (Sclerocarya birrea) is an attractive, established, and persistent tale. This idea now permeates the African tourist industry, historical travelogues, the popular press, and even scholastic works. Accounts of ethanol inebriation in animals under natural conditions appear mired in folklore. Elephants are attracted to alcohol, but there is no clear evidence of inebriation in the field. Extrapolating from human physiology, a 3,000-kg elephant would require the ingestion of between 10 and 27 L of 7% ethanol in a short period to overtly affect behavior, which is unlikely in the wild. Interpolating from ecological circumstances and assuming rather unrealistically that marula fruit contain 3% ethanol, an elephant feeding normally might attain an ethanol dose of 0.3 g kg(-1), about half that required. Physiological issues to resolve include alcohol dehydrogenase activity and ethanol clearance rates in elephants, as well as values for marula fruit alcohol content. These models were highly biased in favor of inebriation but even so failed to show that elephants can ordinarily become drunk. Such tales, it seems, may result from "humanizing" elephant behavior.

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    • "Eur J Wildl Res Furthermore, particular vegetation communities are associated with higher or lower elevations, for example, along a catena sequence (Venter et al. 2003) or with respect to a riparian zone (Rogers and O'Keefe 2003). Independent of vegetation productivity or leaf area, plants along such gradients might vary with respect to presence of key forage resources (e.g., marula, S. birrea; Morris et al. 2006) or overall palatability as a consequence of plant defences (Scholes and Walker 1993). Elephants favour Acacia-marula woodlands in the wet season (Shannon et al., 2006), and some elephants change their seasonal movements in response to the availability of fruits (White 1994). "
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