Trauerschnäpper
Studies were also done to examine the amount of contribution the male European pied flycatcher provided in parental care as well as why some females choose to mate with mated males. When older and younger monogamous males were compared, there was no difference in feeding rate between each nest. When females were studied, scientists found that monogamous and primary females benefited significantly more from the male in terms of parental care than polygynous females did. The latter group could only partially compensate for the absence of a male, leading to secondary females and widows raising fewer offspring than the monogamous pairs did. In the study, differences in mates and the qualities of the territories were slight and therefore not considered, since they lead to no advantages for females to choose between the territories belonging to monogamous or already-mated males. The results of the study suggest that the males can control multiple territories and are thus able to deceive females into accepting polygyny, while the females do not have enough time to discover the marital status of the males.