Biodiversity Group: EVOLUTION IN YOUR BACK GARDEN

People in the UK spend twice as much on bird food than those on mainland Europe and this may have resulted in the British great tits developing longer beaks.  Oxford University, who have been studying great tits in Wytham Woods near Oxford for 70 years, have been collaborating with researchers at the Netherlands Institute of Ecology and the universities of Wageningen, Sheffield, Exeter and East Anglia.  They found that since the 1970s the UK great tits have developed longer beaks than their relatives in the Netherlands suggesting that natural selection is at work.  Further research into great tits with longer beaks found they visited bird feeders more often than birds with shorter beaks, they were in better condition and more successful at reproducing.  Dr Lewis Spurgin, of the School of Biological Sciences at the University of East Anglia says “Although we can’t say definitively that bird feeders are responsible, it seems reasonable to suggest that the longer beaks amongst British great tits may have evolved as a response to this supplementary feeding.” What gives the birds with the longer beaks the advantage?  Maybe they can access food in the feeders more easily or maybe as Dr Spurgin speculated “it could be that they don’t drop seeds when they’re carrying them away.”