Sentence:  . It is remarkable that no less than 4 specimens (309, 345, 348, 357) from the area of <WSD>bastardization</WSD> show formation of eumelanin in numerous of the throat feathers instead of, as was to expected, phaeomelanin. Most probably this phenomenon too is attributable to <WSD>bastardization</WSD>. 
Meaning of the word marked with <WSD> tags:  The creation of offspring from two different species; cross-breeding.