The Effects of Cross-Fostering On Selective Song Learning in Estrildid Finches

Abstract Male zebra finches, Taeniopygia guttata, which have been cross-fostered to Bengalesc finches, Lonchura striata, learn Bengalese finch song elements with as much accuracy as a male learning from his natural father. However, these elements are sung in phrases which are more nearly zebra finch length and lack the repetitiveness typical of the elements in a Bengalese finch phrase. Male Bengalese finches are also capable of learning song from a zebra finch foster-father. Males vary substantially but they tend to produce fewer, more widely spaced zebra finch elements in a Bengalese finch-length phrase. Both species show selective song learning and it is suggested that phrase length and the absence or presence of repeated elements might act as important cues for species-specific learning. Cross-fostered Bengalese finches seem to learn less than cross-fostered zebra finches: possible reasons for this are discussed.