Easy to Train
Chimpanzees are deemed by scientists to be the closest to man of all living 
apes. Consequently, they are fairly easy to train. Several years ago two
married researchers embarked on an interesting projects: they reared and trained
a chimps in the same manner as they would have raised a child. The animal did
beautifully, convincing the couple of the inherent ability of the chimpanzee.
Movie buffs who have seen Tarzan's clever monkey romp through the jungle may
recognize the latent intelligence of those animals.

to go against the grain--My uncle is in favor of some protests, but certain
demonstrations go against his grain.
(to irritate)