Re: Animal drunks

On 10/30/2024 10:29 AM, erik simpson wrote:

This is probably off-topic, but it may be a consequence of evolution, so what the hell..
 https://www.cell.com/trends/ecology-evolution/fulltext/ S0169-5347(24)00240-4
 The evolutionary ecology of ethanol
 Highlights
There is growing evidence that ethanol is encountered frequently enough in the natural world to favour mechanisms enabling its use in multiple animal lineages.
Since the Cretaceous period, fleshy fruits have provided a sugar-rich resource for fermentative yeasts and natural ethanol production. As such, the inclusion of ethanol in animal diets is likely just as ancient.
Moderate ethanol intake is associated with nutritional, medicinal, and cognitive benefits, but many of these remain understudied for non‐human species in natural contexts.
This challenges the current belief that modern humans are the only vertebrate that regularly and uniquely consumes ethanol and leads us to reconsider ethanol’s ecological role and evolutionary impact in nature.
 Abstract
The consumption of ethanol has frequently been seen as largely restricted to humans. Here, we take a broad eco-evolutionary approach to understanding ethanol’s potential impact on the natural world. There is growing evidence that ethanol is present in many wild fruits, saps, and nectars and that ethanol ingestion offers benefits that favour adaptations for its use in multiple taxa. Explanations for ethanol consumption span both the nutritional and non-nutritional, with potential medicinal value or cognitive effects (with social–behavioural benefits) explored. We conclude that ethanol is ecologically relevant and that it has shaped the evolution of many species and structured symbiotic relationships among organisms, including plants, yeast, bacteria, insects, and mammals.
 

One year the University of Utah biology department ran a population genetic selection experiment during an undergraduate genetics lab.  They used a population of flies segregating two alcohol dehydrogenase variants that could be genotyped by electrophoresis enzyme typing.  They crossed two strains of Drosophila so they started with a 50:50 ratio of alleles.  They raised the flies for several generations on fly media with added ethanol.  At the end one allele was obviously taking over the population and was selected for on the ethanol containing medium, but the population raised on normal food was still running around 50:50.
Our simian ancestors were frugivores.  When I took forestry as an undergraduate we were told that bears routinely got sloshed on the berries that they ate and may have enjoyed doing it.
Ron Okimoto