When I was growing up, I was taught that the robin was a member of the thrush family, along with the blackbird, song thrush and fieldfare. This had been the prevailing view since the 1800s. It’s easy to see why early classification experts made this decision. Like many thrushes, the robin haunts gardens where it chases after worms and insects. The robin sings beautifully, as does the blackbird and the song thrush, and like them skulks in the undergrowth for food; it is monogamous, and when perturbed it erects its tail and gives an alarm call as blackbirds do. Although the robin is smaller than thrushes found in the UK, it might be said to have a crudely similar shape.
However, most of these apparent similarities between the robin and members of the thrush family are behavioural, and are not necessarily evidence of a close genetic link or a ‘familial relationship’.
The study of wildlife classification is called taxonomy, and these days the scientists involved have a great deal more to help them make decisions than observation alone. For example, DNA analysis can demonstrate just how closely related one species is to another. The International Ornithological Congress (IOC) now keeps a website showing the currently accepted classification for all birds.
In the 18th century, when Linnaeus first devised the binomial system of Latin names used to identify every species, the robin was originally put into a quite large family of birds that included wagtails and wrens. During the 19th century, this error was realised and it was then that robins were denoted as thrushes.
Using more careful study than was possible in the past, including genetic analysis, it has been shown that the robin is actually in the family as birds known as chats and African flycatchers. To be technical about it, this family is called the Muscicapidae [‘muss–key–cap–ee–dye’], whereas the thrushes are in a family called Turdidae [‘turd–ee–dye’].
The robin is not the only familiar British bird to be placed in the Muscicapidae. As their names suggest, the stonechat and the whinchat are in this ‘chat’ family too. You can see a physical resemblance when you compare them, and also when you look at members of the chat family from Africa as their size and body shape is similar.
It’s a different story for the American robin. This bird was named by early settlers after its European counterpart because it has a red breast. It is a bigger bird, and it is in fact a true member of the thrush family. There is also a whole family of beautiful birds in the southern hemisphere known as Australasian robins, but these are in yet another completely different family. Our European robin is not closely related to any of these.
So remember, when you next see a robin you are looking at a ‘chat’ not a ‘thrush’, and that the stonechat is a closer cousin than the blackbird.