After taking a number of photographs on 6 February 2019 of feeding Great Tits, Parus major, it wasn’t until looking at the images on the computer that I could see two showed the bird’s tongue.
The tongues of birds come in many shapes and sizes and, if they were more readily visible, could be used to help identify the species. Although they superficially look like our own tongues those of birds are much more species specific.
Two good examples to illustrate this are a hummingbird’s tongue, which needs to be long and flexible to get at the nectar way down in a flower. Compare that with the tongue of a penguin which has numerous large, backward pointing papillae, or barbs, covering the surface of the tongue. These, in partnership with similar barbs on the roof of the penguin’s mouth, help it catch and hold on to slippery fish.
The Great Tit has a general-purpose tongue, i.e. it doesn’t show noticeable dietary adaptations. This means it can eat a variety of foods e.g. seeds, insects, grain, peanuts, etc. So, the upside-down bird in these photos is probably not simply trying to break a peanut to get a large piece but is constantly ‘grabbing’ small bits of the nut each time it pecks at it. If you look at the heavily cropped photo you can see a white coloured tip to the bird’s tongue. This is like a feathering of the tip which helps it grab the small bits of nut. There may also be a sticky fluid involved here to help in the process.
A fascinating bit of detail about birds which may whet your appetite (or tongue!) to discover more about avian tongues and the diversity that evolution has brought to them.