The enthusiasm to feed birds may have caused a beloved bird species in the United Kingdom to evolve longer beaks than their European kin. According to new research, the backyard evolution was likely caused by the widespread use of birdfeeders across the UK.
Long-Term Study Finds Quick Evolution
Researchers from the Universities of East Anglia, Exeter, Oxford, Sheffield, and Wageningen, and the Netherlands Institute of Ecology (NIOO-KNAW) collaborated to conduct a long-term study on the great tit populations in Wytham woods in Oxford, and in Veluwe and Oosterhout in the Netherlands.
With the help of 70 years' worth of historical data gathered by researchers from Oxford University, researchers now find that the great tits in the UK's beaks have clearly grown longer over time compared with the beaks of their counterparts in Europe. Electronic tags also revealed the amount of time that the birds spent at bird feeders, revealing that birds with the longer beaks visited bird feeders more often. Interestingly, people in the UK spend twice as much on birdfeeders and birdseed compared to other European countries.
The evidence suggests that supplementary feeding from the automated bird feeders may have led to the evolution of longer beaks. Essentially, researchers found that as a result of widespread bird feeder usage in the UK, British great tits evolved longer beaks between the 1970s and today, which is a fairly short amount of time for this kind of change.
Natural Selection
Gene sequencing revealed that the genes responsible for the beak lengthening of the British great tit closely match the genes responsible for determining face shape among humans. The identified genes were also associated with the genes in Darwin's study of finches.
"We now know that this increase in beak length, and the difference in beak length between birds in Britain and mainland Europe, is down to genes that have evolved by natural selection," said Professor Jon Slate of the University of Sheffield.
Interestingly, the rapid evolution of the British birds' beaks has so far proven advantageous to the species. Researchers found that the birds with longer beaks exhibited more successful reproduction compared with the birds with shorter beaks. According to Dr. Lewis Spurgin of the University of East Anglia, the birds with the advantage of having better access to food are generally in better condition and can reproduce and perform better than the birds without the said advantage.
Now, researchers are conducting a follow-up study and have so far found evidence that the birds with longer beaks are specific to the UK.
The study was published in the journal Science.