Almost anyone who has read a travel brochure about Africa has heard of a story ----- that elephants can get drunk by eating the fermented   marula fruit rotting   on the ground. Books have even been written to prove the truth of the phenomenon. But a study published in the journalPhysiological and Biochemical Zoologytells a very different story. Steve Morris, a biologist at the University of Bristol in England and an author of the study, says there is nothing in the biology of either the African elephant or the marula fruit to support the stories. Morris says, "People just want to believe in drunken elephants." The marula tree, a member of the same family as the mango  , grows widely in Africa. Its sweet, yellow fruit is used for making jam, wine and beer. "The first mistake of the drunken-elephant theory is that it's unlikely that an elephant would eat the fruit if it were rotten," Morris says. "Elephants eat the fruit right off the tree, not when it's rotten on the ground," he explains. Other experts add that if an elephant were to eat the fruit on the ground, it wouldn't wait for the fruit to ferment. Michelle Gadd, an African wildlife specialist, says that elephants and many other animals, including birds and monkeys, are too fond of marula fruit to let it rot. If fermented fruit on the ground is out of the question, so is the concept that the fruit could ferment in the stomach of elephants, according to the study authors. Food takes between 12 and 46 hours to pass through an elephant's digestive   system, the authors point out, which is not enough for the fruit to ferment. Supposing that _ happened, it's still highly improbable that the food would produce enough alcohol to make an elephant drunk. Through calculations of body weight, elephant digestion rates, and other factors, the authors conclude that it would take about 1.9 litres of alcohol to make an elephant drunk. Which of the following is Mr. Morris's opinion?
Elephants prefer mangoes to the marula fruit. Elephants will not eat the marula fruit if it is rotten. The marula tree and the mango belong to different families. There are several connections between elephants and the marula fruit.