A wild mammal closely resembling the earliest primates is drinking palm beer on a daily basis since maybe millions of years. Nevertheless, this Malaysian treeshrew is never drunk.
This suggests a beneficial effect, and sheds a whole new light on the evolution of human alcoholism. In the renowned scientific journal PNAS an international team led by German biologists Frank Wiens and Annette Zitzmann from the University of Bayreuth explains the details of the first recorded chronic alcohol intake in the wild.
A wild mammal closely resembling the earliest primates is drinking palm beer on a daily basis since maybe millions of years. Nevertheless, this Malaysian treeshrew is never drunk. This suggests a beneficial effect, and sheds a whole new light on the evolution of human alcoholism. In the renowned scientific journal PNAS (publication in PNAS online Early Edition scheduled for July 28), an international team led by German biologists Frank Wiens and Annette Zitzmann from the University of Bayreuth explains the details of the first recorded chronic alcohol intake in the wild.
Alcohol use and abuse can no longer be blamed on the inventors of brewing of about 9,000 years ago. So far, the current theories on alcoholism have stated that mankind and its ancestors were either used to take no alcohol at all or maybe only low doses via fruits - before the onset of beer brewing. As brewing is such a recent event on the evolutionary time scale, we were not able to develop an adequate defence against the adverse effects of alcohol and the partly hereditary addiction. Mankind is suffering from an evolutionary hangover, as they say.
Contrary to this belief, chronic high consumption of alcohol already occurred early on in primate evolution according to an international team of scientists from Germany, Canada, Luxemburg, Switzerland, and Malaysia. First author Frank Wiens from the University of Bayreuth and the Central Institute of Mental Health in Mannheim specializes in evolutionary physiology: 'Alcohol consuming treeshrews are not real shrews. In fact, they belong to the primates' closest living relatives and are ecologically and behaviourally comparable to their extinct ancestors that lived more than 55 million years ago. Studying these fascinating creatures is an unexpected golden opportunity to learn about the causes and consequences of real-life drinking.'
Neither tipsy nor tame, the wild pentailed treeshrew Ptilocercus lowii from the West-Malaysian rainforest spends its nights looking for and licking fermented nectar of the bertam palm. 'This palm is brewing its own beer with the help of a team of yeast species, several of them new to science,' explains Wiens. The highest alcohol percentage the scientists could measure in the nectar was an impressive 3.8 %. 'It reaches among the highest alcohol contents ever reported in natural food.' The palm tree keeps its nectar beer flowing from specialised smelly flower buds for a month and a half before the pollen is ripe, probably to keep a guaranteed clientele of potential pollinators visiting.
In contrast to most plants the bertam palm flowers almost year-round. The alcohol consumption of treeshrews and their drinking companions - six other mammal species are also "regulars" - is therefore chronic. Chronic indeed, because this drinking habit of the pentailed treeshrew could already have been established over 55 million years ago.
As drunkenness is extremely dangerous for small mammals with plenty of lurking predators around, drinking to intoxication does not make sense. Still, with hair sample analysis for ethyl glucuronide, an indicator for chronic alcohol consumption, the team showed that the pentailed treeshrew takes in alcohol at a rate dangerous to other mammals. Treeshrews are very hard to see or catch, but video surveillance at palm sites and spying on several radio-collared individuals showed that they drank nectar for more than two hours each night - more time than they used for any other food source.
Although their size is in between that of a mouse and a rat and they weigh a mere 47 grams, they did not show any motion coordination problems or other signs of being drunk. Compared to human standards, pentailed treeshrews would be drunk once in every three nights. The treeshrews might break down the ingested alcohol in an unusually efficient manner.
That the threeshrews are not drunk does not mean that they are not affected by the alcohol in a low dose. What is more, Wiens believes that there are actually positive psychological effects of the treeshrews' alcohol consumption: 'The trait of alcohol consumption is actively maintained during evolution, so the overall effect must be beneficial. Future research has to prove if this is true and may explain past and current human drinking habits.'
Jürgen Abel | idw
Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute
Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy