Can alcohol (ethanol) exist in nature without the intervention of man? The other day, I came across this article: Chimpanzees found routinely drinking alcohol in the wild.

In this article, David Mercer claims that "Primates in Guinea drank fermented palm sap using a leafy tool as a sponge."


  Scientists have discovered a group of booze-loving apes who may hold the key to why humans enjoy drinking alcohol.
  
  Experts say they have found the first empirical evidence of “long term and recurrent ingestion of ethanol” among apes in nature.
  
  hey observed wild chimpanzees in the town of Bossou in Guinea, west Africa, over 17 years and watched as the primates drank fermented palm sap using a leafy tool as a sponge.
  
  The chimpanzees consumed the alcoholic beverage, often in large quantities, despite an alcohol presence of up to 6.9 per cent ABV - the equivalent of a strong ale, according to a study published by the Royal Society.
  
  The amount of alcohol ingested ranged from about 2.5 to 84ml and there was no difference between males and females.
  
  Experts said that, unlike other examples of primates ingesting alcohol, such as introduced green monkeys targeting tourist cocktails in the Caribbean, the chimpanzees' attraction to fermented palm sap at Bossou was not a result of provisioning by local people.


My question is this: Do other naturally occurring alcohol (ethanol) drinks exist in a natural setting as in forests, plains, savannas, etc., without man's intervention on a regular basis?
All fruit when crushed or rotten will have naturally occurring alcohol. As long as there is sugar, yeast and water alcohol will happen. Most commercially purchased fruit juice has a small amount of alcohol in it when you purchase it. 


  Low-alcoholic beverage[edit]
  Sparkling cider, sodas, and juices naturally contain trace amounts or no alcohol. Some fresh orange juices are above the UK 'alcohol free' limit of 0.05% ABV, as are some yogurts and rye bread.
  
  Ethanol distillation is used to separate alcoholic beverages into what are advertised as non-alcoholic beverages and spirits; distilled wine produces low alcohol wine and brandy (from brandywine, derived from Dutch brandewijn, "burning wine"),1 distilled beer may be used to produce low-alcohol beer and whisky.
  
  However alcoholic beverages cannot be further purified to 0.00% alcohol by volume by distillation. In fact, most beverages labeled non-alcoholic contain 0.5% ABV as it is more profitable than distilling it to 0.05% ABV often found in products sold by companies specializing in non-alcoholic beverages.


There are many stories about deer, bear and other wild animals getting drunk on apples that have fallen and rotted on the ground. Do animals get drunk


  “I’ve watched white-tailed deer eating fermented apples in orchards," Moore says. They get pretty “sleepy,” even “stumble-y.” It’s a common observation in apple-growing regions, he adds.


But I think you want to know if there are naturally occurring drinks other than eating a bunch of rotten fruit and there are only a couple of that I have heard of and the one you mention in your question was one and the other was naturally occurring mead which happens when water gets into a beehive with honey in the comb. Honey fermenting in the comb


  To produce honey, bees collect nectar from flowers and add enzymes from their honey stomachs. Once the mixture is stored in cells, the bees fan it with their wings until it dehydrates to a moisture content of about 16 to 18.5 percent. If the moisture content is higher than that, the bees simply won’t cap it. If cold weather arrives before the honey is capped, it will sit open in the hive and may eventually ferment.