人類通常被認為是唯一能定期攝入酒精的動物,，但是科學家如今發(fā)現(xiàn)馬來西亞的羽尾樹鼩依靠一種相當于啤酒的飲食生活,，而且可能已經(jīng)這樣生活了長達5500萬年之久。樹鼩被認為與所有現(xiàn)存靈長類動物的最晚近共同祖先非常相似,，這增加了人類對酒精的敏感可能是一種進化特征的可能性,。樹鼩以玻淡棕櫚（bertam palm）花蕾的花蜜為食。它的花蜜發(fā)酵產(chǎn)生了多達3.8%的酒精,。這種棕櫚樹終年以一種復雜的時間表產(chǎn)生花蜜,，這看上去是為了讓樹鼩的授粉作用最大化,。相關論文發(fā)表在美國《國家科學院院刊》（PNAS）上。
Frank Wiens及其同事攝像記錄了樹鼩常規(guī)的夜間進食時段,，并跟蹤了用無線電標記的樹鼩的運動,，從而估計它們酒精攝入量。盡管按照人類的標準,，一只樹鼩在任何一個夜晚都有36%的酒醉的可能性,，這組科學家沒有觀察到這種動物的任何酒醉的跡象。他們對毛發(fā)的生物標記物的分析證實了這種動物的高酒精攝入量,，這讓他們提出樹鼩非?？赡軗碛幸环N有效地降解酒精的生物化學路徑。（生物谷Bioon.com）
生物谷推薦原始出處：
PNAS,，doi: 10.1073/pnas.0801628105,，F(xiàn)rank Wiens，Rainer Spanagel
Chronic intake of fermented floral nectar by wild treeshrews
Frank Wiens*,†,‡, Annette Zitzmann*,§, Marc-André Lachance¶, Michel Yegles‖, Fritz Pragst**, Friedrich M. Wurst††, Dietrich von Holst*, Saw Leng Guan‡‡, and Rainer Spanagel†
+Author Affiliations
*Tierphysiologie, Universität Bayreuth, 95440 Bayreuth, Germany;
†Psychopharmakologie, Zentralinstitut für Seelische Gesundheit, 68159 Mannheim, Germany;
§Zoologisches Institut, Johann Wolfgang Goethe-Universität, 60054 Frankfurt am Main, Germany;
¶Department of Biology, University of Western Ontario, London, ON, Canada N6A 5B7;
‖Laboratoire National de Santé, Toxicologie, Université du Luxembourg, 1511 Luxemburg;
**Toxikologische Chemie, Institut für Rechtsmedizin, 14195 Berlin, Germany;
††Universitäre Psychiatrische Kliniken, 4025 Basel, Switzerland; and
‡‡Forest Research Institute, 52109 Kuala Lumpur, Malaysia
Edited by May R. Berenbaum, University of Illinois at Urbana–Champaign, Urbana, IL, and approved May 21, 2008 (received for review February 20, 2008)
Abstract
For humans alcohol consumption often has devastating consequences. Wild mammals may also be behaviorally and physiologically challenged by alcohol in their food. Here, we provide a detailed account of chronic alcohol intake by mammals as part of a coevolved relationship with a plant. We discovered that seven mammalian species in a West Malaysian rainforest consume alcoholic nectar daily from flower buds of the bertam palm (Eugeissona tristis), which they pollinate. The 3.8% maximum alcohol concentration (mean: 0.6%; median: 0.5%) that we recorded is among the highest ever reported in a natural food. Nectar high in alcohol is facilitated by specialized flower buds that harbor a fermenting yeast community, including several species new to science. Pentailed treeshrews (Ptilocercus lowii) frequently consume alcohol doses from the inflorescences that would intoxicate humans. Yet, the flower-visiting mammals showed no signs of intoxication. Analysis of an alcohol metabolite (ethyl glucuronide) in their hair yielded concentrations higher than those in humans with similarly high alcohol intake. The pentailed treeshrew is considered a living model for extinct mammals representing the stock from which all extinct and living treeshrews and primates radiated. Therefore, we hypothesize that moderate to high alcohol intake was present early on in the evolution of these closely related lineages. It is yet unclear to what extent treeshrews benefit from ingested alcohol per se and how they mitigate the risk of continuous high blood alcohol concentrations.
