Calling a person with African heritage a monkey takes us back to the 18th century when the africans were abused by their slave masters and one of the common abuse was calling them apes or monkeys. Just we think slavery is a ghost of the past, if such taunts surface up again it is indeed very sad!
It is perhaps more out of ignorance and no racist intent is involved in such comments, atleast I hope. But in such a sensitive issue, ignorance is not an excuse.