The results showed that more than 80% of trends between 1976 and 2005 indicated earlier seasonal events. On average, the study showed the seasonal timing of reproduction and population growth shifted forward by eleven days over the period, and that the change has accelerated recently.The article goes on to quote various campaigners and academics as suggesting that this finding is quite possibly a sign of man-made global warming and certainly a serious cause for concern.
But I wonder.
How much does a study lasting 30 years tell us about what it is normal over the period that life has existed on this planet?
There is a view implicit in much popular discussion of man-made global warming that until very recently the planet's climate was stable and benign. Only recently, it maintains, has that climate changed to threaten man. I think this view is mistaken and is another manifestation of our tendency to see whatever was around in our youth as natural and right.
Surely the truth is that our climate has always been changing? (This does not preclude the possibility that some of the recent change is the cause of man-made pollution of the atmosphere.)
Further, species have always been adapting more or less successfully to that change. It is odd in a society where Darwin is now the most honoured intellectual figure (far more than, say, Freud or Marx) that we regard the possibility of species struggling to stay in existence as such an aberration from the natural order of things.
None of this offers any reason why we should not try to conserve species that are under threat. But I suspect that spring coming 11 days earlier after 30 years is the natural order of things, not a cause for deep concern.