The Lesser Black-Back Gull.

Travelled from Mbra down to Bristle today, left in a blizzard with 3 inches of snow on the ground and the train was 4 minutes late departing. We were repeatedly informed that the train was making up time, which it did so successfully that it arrived 70 minutes late (in a blizzard). However, at least there was no snow on the ground.

While plucking up the energy to walk to the bus stop I sat on a bench on the platform with a real cup of coffee and a Danish, this chap wanted a piece of the action but was struggling on the courage front. The crumbs were two feet away from my feet while cowardice cut in at three.

Homo sapiens does like to categorise things, for example, no sooner do you define say - males and females - and someone will find a hermaphrodite. It doesn't matter what boundary you specify, something will come along and firmly plant a foot on each side.
Here in the UK we have two closely related gulls, the lesser black-backed and the and the much paler herring. If you travel East, you find that the herring gull disappears, travel further and the black-backs start to fade. Keep going and eventually, by the time you arrive back home, they have faded all the way into herring gulls which are now unable to breed with the black-backs.
By definition, two populations that can't inter-breed constitute separate species, so where did they change from one to the other?
As they used to say, "Answers on a post-card, please."