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.

7 Reads
  • Source
    • "Another important factor that leads to house damage is alcohol. Elephants are fond of alcoholic liquor (Morris et al., 2006; Sukumar, 1993), and raid village distilleries where alcohol is brewed and stored (Sukumar, 2003). Popular reports of elephants raiding village breweries are widespread (Barua, 2010). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Human-wildlife conflicts impact upon the wellbeing of marginalised people, worldwide. Although tangible losses from such conflicts are well documented, hidden health consequences remain under-researched. Based on preliminary clinical ethnographic inquiries and sustained fieldwork in Assam, India, this paper documents mental health antecedents and consequences including severe untreated psychiatric morbidity and substance abuse. The case studies presented make visible the hidden mental health dimensions of human-elephant conflict. The paper illustrates how health impacts of conflicts penetrate far deeper than immediate physical threat from elephants, worsens pre-existing mental illness of marginalised people, and leads to newer psychiatric and social pathologies. These conflicts are enacted and perpetuated in institutional spaces of inequality. The authors argue that both wildlife conservation and community mental health disciplines would be enhanced by coordinated intervention. The paper concludes by generating questions that are fundamental for a new interdisciplinary paradigm that bridges ecology and the clinic.
    Health & Place 07/2012; 18(6). DOI:10.1016/j.healthplace.2012.06.019 · 2.81 Impact Factor
  • Source
    • "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). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Foraging behaviour and habitat selection occur as hierarchical processes. Understanding the factors that govern foraging and habitat selection thus requires investigation of those processes over the scales at which they occur. We investigated patterns of habitat use by African elephants (Loxodonta africana) in relation to vegetation greenness to investigate the scale at which that landscape attribute was most closely related to distribution of elephant locations. We analysed Global Positioning System radio-collar locations for 15 individuals, using the Normalized Difference Vegetation Index as a representation of vegetation greenness in a Geographic Information Systems framework. We compared the importance of vegetation greenness at three spatial scales: the total home range, the seasonal home range and the 16-day home range. During the wet season, seasonal home ranges for both sexes were associated with intermediate greenness within the total home range; there was no evidence of selection based on greenness at finer scales. During the dry season, the strongest associations were within the 16-day home range: individual locations for males tended to be in areas of intermediate greenness, and those for females were in areas of intermediate and high greenness. Our findings suggest that the role of vegetation greenness varies with the scale of analysis, likely reflecting the hierarchical processes involved in habitat selection by elephants. KeywordsAfrican elephant–Habitat selection– Loxodonta africana –Normalized Difference Vegetation Index (NDVI)–Scale
    European Journal of Wildlife Research 06/2011; 57(3):537-548. DOI:10.1007/s10344-010-0462-1 · 1.63 Impact Factor
  • Source
    • "Both natural sources of ethanol availability contrast with manmade fermented beverages; ethanol concentrations in ripe fruits are extremely low in comparison to levels experienced by people who consume alcoholic beverages: one or two orders of magnitude below typical concentrations in beer and wine (3–6% and 8–12%, respectively, or 522–1043 mM and 1391–2086 mM). Therefore, reports of mammals inebriated with alcohol under natural conditions are only folk tales [18], and even frequent consumption of ethanol-rich fruits does not allow excessive ethanol consumption under human standards. Availability of ethanol at concentrations higher than those attained by yeast fermentation is a very recent event in evolutionary history. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Alcohol dehydrogenase (ADH) activity is widely distributed in all phyla. In animals, three non-homologous NAD(P)(+)-dependent ADH protein families are reported. These arose independently throughout evolution and possess different structures and mechanisms of reaction: type I (medium-chain) ADHs are zinc-containing enzymes and comprise the most studied group in vertebrates; type II (short-chain) ADHs lack metal cofactor and have been extensively studied in Drosophila; and type III ADHs are iron-dependent/-activated enzymes that were initially identified only in microorganisms. The presence of these different ADHs in animals has been assumed to be a consequence of chronic exposure to ethanol. By far the most common natural source of ethanol is fermentation of fruit sugars by yeast, and available data support that this fruit trait evolved in concert with the characteristics of their frugivorous seed dispersers. Therefore, if the presence of ADHs in animals evolved as an adaptive response to dietary ethanol exposure, then it can be expected that the enzymogenesis of these enzymes began after the appearance of angiosperms with fleshy fruits, because substrate availability must precede enzyme selection. In this work, available evidence supporting this possibility is discussed. Phylogenetic analyses reveal that type II ADHs suffered several duplications, all of these restricted to flies (order Diptera). Induction of type II Adh by ethanol exposure, a positive correlation between ADH activity and ethanol resistance, and the fact that flies and type II Adh diversification occurred in concert with angiosperm diversification, strongly suggest that type II ADHs were recruited to allow larval flies to exploit new restricted niches with high ethanol content. In contrast, phyletic distribution of types I and III ADHs in animals showed that these appeared before angiosperms and land plants, independently of ethanol availability. Because these enzymes are not induced by ethanol exposure and possess a high affinity and/or catalytic efficiency for non-ethanol endogenous substrates, it can be concluded that the participation of types I and III ADHs in ethanol metabolism can be considered as incidental, and not adaptive.
    Chemico-biological interactions 02/2011; 191(1-3):14-25. DOI:10.1016/j.cbi.2011.02.008 · 2.58 Impact Factor
Show more


7 Reads
Available from