The breed's keen intelligence, sharp bark, acute hearing and innate ability to distinguish friend from foe made them perfectly suited to these tasks. (petwave.com)
You must find a way to distinguish friend from foe before it is too late! (gamesauce.biz)
The wisdom these gray elders possess is the ability to distinguish friend from foe among other elephant families, which they encounter about 25 times a year in the Amboseli Elephant Research Project area in Kenya. (scientificamerican.com)