Developmental changes in the body proportions of western North Pacific Bryde’s whales (Balaenoptera edeni) were investigated by examining the proportion of each body part to the total body length. The head and chest ...Developmental changes in the body proportions of western North Pacific Bryde’s whales (Balaenoptera edeni) were investigated by examining the proportion of each body part to the total body length. The head and chest region increased to a certain body length;subsequently, the length of head region stabilized, and that of the chest region decreased. The length of the abdominal region remained constant to a certain body length and subsequently showed a marked increase, and that of the tail region decreased consistently. The length of dorsal fin and flukes decreased consistently, whereas that of the flippers remained constant to a certain body length and subsequently decreased. The relative growth pattern determined by an allometric analysis was positive for the head region but negative for the lower body part, flippers, flukes, and dorsal fin. Both sexes demonstrated the same growth pattern, but the coefficients differed. This is the first study to investigate developmental changes in the body proportions of Bryde’s whales using more than 700 specimens covering a wide body length range. We believe that the results of this study will contribute to various research fields, including taxonomy, phylogeny, and feeding ecology of this species.展开更多
文摘Developmental changes in the body proportions of western North Pacific Bryde’s whales (Balaenoptera edeni) were investigated by examining the proportion of each body part to the total body length. The head and chest region increased to a certain body length;subsequently, the length of head region stabilized, and that of the chest region decreased. The length of the abdominal region remained constant to a certain body length and subsequently showed a marked increase, and that of the tail region decreased consistently. The length of dorsal fin and flukes decreased consistently, whereas that of the flippers remained constant to a certain body length and subsequently decreased. The relative growth pattern determined by an allometric analysis was positive for the head region but negative for the lower body part, flippers, flukes, and dorsal fin. Both sexes demonstrated the same growth pattern, but the coefficients differed. This is the first study to investigate developmental changes in the body proportions of Bryde’s whales using more than 700 specimens covering a wide body length range. We believe that the results of this study will contribute to various research fields, including taxonomy, phylogeny, and feeding ecology of this species.