Almost Like a Whale

Most people can tell gulls from terns. Many can separate the herring gull from the lesser black-backed (look at the back, which is pale in the first and dark in the other). My friend the glaucous gull is more subtle - as large as a greater black-backed, but as pale as a herring gull, without its black wingtips. A real expert can even sort out the Iceland gull (like a small glaucous, with longer wings). Birders still argue about the existence of the yellow-legged gull as a distinct entity, but its 'bold, confident look' is said to be diagnostic.

But how to deal with variation within each bird? Herring gulls from Estonian bogs had, some say, yellow legs, but these have now disappeared in favour of the pink legs found everywhere else. Those from the Atlantic islands are on occasion blown to Britain. Their backs are almost as black as those of lesser black-backeds. A 'generally stouter bill' might help, but what use is a generalization when an individual must be sorted out? If the despondent twitcher were to travel to Iceland he would be frustrated by hybrids between the Iceland gull and its commonplace relatives. Where does he put his tick?

Species and nations have a lot in common. What, for example, is a German? The tribe has a shared and guttural means of communication that interrupts intercourse of most kinds, but the character is equivocal, for Austrians speak the same language. Since 1913, the country has defined its own citizens by descent, by German blood (whatever that might be). It includes within the realm the remnants of the Saxon diaspora (many of whom - Romanians included - cannot speak German at all), but cuts out children born in Berlin of Turkish parents. One badly behaved teenager was deported to Turkey even though he was born in Germany; while at the same time a hundred thousand Romanian-speakers of approved blood were allowed in. Until the fall of the Berlin wall, indeed, a geographical barrier made many German citizens more alien to each other than Westerners or Easterners were to the French or the Poles. A century ago German identity itself meant little, as there were only Prussians, Bavarians and Rhinelanders, political entities of their own, each now reduced to variants in some greater Teutonic whole.

University Southern California Charles Darwin: he described the process of natural selection, the theory of evolution waited for an advance in genetic knowledge.