Its my understanding that our native European robin is joined by robins from colder parts of Europe, such as Scandinavia and thats why we see more of them around in the autumn and winter.
Essentially a woodland bird belonging to the thrush family, thats learnt to adapt very well to our gardens.
I'll look for that divebuddy. Now I haven't checked this so may be wrong but I think in days of old, because the 2 sexes were indistinguishable, it was originally thought that all robins were males and the females of the species were wrens.