The Great tit is a small, roundish bird (ca. 14 cm) with a short beak. It has a characteristic yellow underside which has a longitudinal strip on the chest, as if it were wearing a tie. In the male, this black stripe is usually wider than in the female. It has a black head with white cheeks. Its back is of a grey-green colour and it has a white stripe on the wing. It feeds on small invertebrates, such as various invertebrates (grasshoppers, earwigs, flies, ants, beetles), spiders, caterpillars and snails. It has many different calls which may initially confuse us while trying to recognise it, but its song is a characteristic "tit-tit-tit" - from which it also takes its name.