Pigeons can distinguish words from non-words: Study
According to a research by researchers in New Zealand and Germany, pigeons can learn to distinguish between real words and non-words in English, becoming the first non-primate species with "orthographic" abilities. The test-pigeons were able to identify words by visually processing the letter combinations and were able to build vocabularies ranging from 26-58 words and more than 8,000 non-words.  