bread breadcrumbs crumbs Morning table background birds brown buff Camouflage camouflaged climate-tolerant common common-pest contrast dark ever-expanding populations fauna gray grey house sparrows insect-eaters introduced-species Matthew 10:29 mottled Old-World-sparrows passer domesticus passerine-birds pest plump powerful-beaks prolific seed-eaters small social sparrow sparrows textures true-sparrows two-a-penny worldwide-distribution climate tolerant feeding pavement paving