Urban great tits have paler plumage than their forest-living relatives
The distinctive yellow color in the great tit's feathers comes from pigments called carotenoids which are found in food sources. The great tits get these nutrients from the insects they eat, who, in turn get carotenoids from the plants they feed on. This new research suggests that urban great tits are not able to consume as many carotenoids from their food as their countryside counterparts, and possibly fewer than they might need to stay as healthy.
