Don't tell the Immigration Control Platform, but it seems that evolution has left some people more naturally suited than others to living in this part of the world. It's the flipside of the poor adaptive fit that has seen melanomas sprouting all over people of northern-European origin in places like Miami and Brisbane: people more suited to sunnier climes but living in our overcast latitudes are developing rickets.
Yes, good old Victorian rickets, the disease of bent limbs and rosary-shaped skin marks that affected four out of five children in the dismal housing conditions and smoggy air of late-19th-century London, has made a comeback in Britain, we learned on The ABC of Vitamins (BBC Radio 4, Tuesday). Presumably we can expect the same here among Ireland's new dark-skinned population.
Rickets is connected to a shortage of vitamin D, and so it can be simply treated with supplements, but it is properly understood (as it was for centuries, before confusion about heredity and over-emphasis on drugs set in) as a disease of sunlight deficiency. Pale-pink people have little pigment to block the sun from getting through - an adaptation for exploiting the wee bits of sun we see in this part of the world. But folks from nearer the equator, who retain the heavier pigmentation of our common evolutionary ancestors, are a bit stuck for sunlight around here.
The doctor interviewed didn't reckon that our current sun-shy culture was contributing to the problem: sunscreens are not enough to stop most white people from producing vitamin D, apparently. But among Asians in Bradford, Orthodox Jews in Manchester and other populations with origins in sunny places, rickets is on the increase. Asian girls are apparently at particularly great risk because of the rise in strict religious practice that sees their skin covered nearly all the time they are outdoors. The programme brought us to a doctor's surgery, where 18-month-old Zena was being diagnosed. Britain's Department of Health recommends vitamin D supplements for Asians (and indeed for pregnant women of whatever origin), but the message doesn't seem to be getting through. Is it time to start encouraging people back out into the sun?
Last week this column discussed one manifestation of ever-optimistic sunshine culture: Test Match Special (BBC Radio 4 long-wave and medium-wave), back this weekend in Heddingley for more England v West Indies. As a result of those scribblings, I had a helpful e-mail from a fan of what the cognoscenti apparently call TMS - so afflicted with TMS, indeed, that she now watches cricket on Channel 4 with the TV sound down and the radio on. (It was reassuring to read that it's not just radio reviewers who indulge in such bizarre behaviour.)
Anyway, this correspondent gave me a steer on the highly capable woman who has broken into the venerated TMS commentary box: Donna Symmonds, an attorney from a posh background in Barbados, is the trailblazer and subject of much praise and equal scepticism in the cricket world - you only need think about those feminist strongholds of Australia, Pakistan and the Daily Telegraph. Subject of praise here in the past but a certain amount of scepticism this summer is Maura O'Neill, coming now toward the end of an extraordinarily long stretch filling in for Marian Finucane (who fully deserves the nine-week holiday, let it be said). The programme, with the inevitable title of Maura O'Neill (RTE Radio 1, Monday to Friday), has been a mixed bag over these summer months, its presenter usually displaying all the charm and most of the intelligence required for the task, but her verbal acuity sometimes letting her down. It's not a fatal flaw: this programme, free of music and low on ads, is, after all, a particularly hard station.
And O'Neill was considerably stronger this week when the show turned to the ubiquitous educational topics that every year around this time ease us gradually out of silly season. With her background in teaching and as presenter of You Live and Learn, O'Neill could be expected to earn honours in this subject, and so she did. Inevitably there was the profound irony of teachers filling studios and an hour of prime airtime to complain about the media hype around the Leaving Cert, but of course they had a point. Mick Sheridan, a principal from St Killian's in Bray, Co Wicklow, expressed quite appropriate dismay about Wednesday's TV news close-up of a deeply disappointed girl; the audio version on Wednesday's News at One (RTE Radio 1, Monday to Friday) was equally disgraceful. A new series from tireless Colm Keane - an invader of privacy only when he's got an invitation - is always welcome. His latest, The Uncivil War (RTE Radio 1, Sunday), sets out to make a much-discussed period of 20th-century Irish history into powerful, pop-flavoured radio. This week's programme, complete with plenty of dramatic music and sharp soundbites from local historians and contemporary eyewitnesses, dealt with the killing of Michael Collins at Beal na Blath.
"His death," Keane told us with a characteristic redundant verbal hammerblow, "became one of the great enduring mysteries and legends in Irish political history." But the strength of this programme was in the combination of vivid, almost pictorial detail and genuine, edgy excitement in the voices telling the story.
It remains to be seen whether he can sustain that through the series, or add much to listeners' understanding of the big picture. But as an exercise in drawing small pictures that could bridge a gap of 78 years, this first programme was really outstanding.