There's a chapter about how animals get high in the book I posted about a
few weeks ago, 'Wild Health' by Cindy Engel. She argues that although
getting drunk can be bad for animals (e.g. makes them more vulnerable to
predators), the reason they eat fermenting fruits when available is simply
because they are a such good source of energy. She goes on to speculate
that this could be why some humans have a taste for alcohol - not such a
good thing these days when it is so readily available.
Jo