DNA sequence analysis of a North Pacific humpback whale (Megaptera novaeangliae) placenta

摘要

Whales residing in their natural, noncaptive environments present a particular challenge to the direct observation of parturition and the subsequent analysis of afterbirth tissues. For many years the research community has believed that the Hawaiian Islands serve as one of the winter calving grounds for the North Pacific humpback whale, Megaptera novaeangliae. Direct evidence, however, had not been reported. In 1997 the analysis of a large placenta encountered in the Hawaiian winter grounds of the humpback whale was documented but definitive identification of the source species was not possible. In this report we describe the DNA sequence analysis, by polymerase chain reaction, which was performed on the tissue obtained from that placenta to identify its source. It was concluded from the analysis that the unknown placental tissue originated from a humpback whale. These results have important implications concerning humpback whale reproduction, since this molecular confirmation serves as direct evidence of a humpback whale birth in the Hawaiian winter grounds.