4.6 Article

A new archaic baleen whale Toipahautea waitaki (early Late Oligocene, New Zealand) and the origins of crown Mysticeti

期刊

ROYAL SOCIETY OPEN SCIENCE
卷 5, 期 4, 页码 -

出版社

ROYAL SOC
DOI: 10.1098/rsos.172453

关键词

Cetacea; mysticete; feeding strategy; filter-feeding; specialist/generalist; opportunist

资金

  1. University of Otago Doctoral Scholarship
  2. Japan Society for the Promotion of Science Postdoctoral Fellowship
  3. National Geographic Society, Washington, DC [3542-87, 3657-87, OU 21981]

向作者/读者索取更多资源

A new genus and species of extinct baleen whale (dagger)Toipahautea waitaki (Late Oligocene, New Zealand) is based on a skull and associated bones, from the lower Kokoamu Greensand, about 27.5Ma (local upper Whaingaroan Stage, early Chattian). The upper jaw includes a thin, elongate and apparently toothless maxilla, with evidence of arterial supply for baleen. Open sutures with the premaxilla suggest a flexible (kinetic) upper jaw. The blowhole is well forward. The mandible is bowed laterally and slightly dorsally; unlike the Eomysticetidae, there are no mandibular alveoli, and the coronoid process is tapered and curved laterally. Jaw structure is consistent with baleen-assisted gulp-feeding. The age of early Chattian makes (dagger)Toipahautea a very early, if not the oldest named, toothless and baleen-bearing mysticete, suggesting that the full transition from toothed to baleen-bearing probably occurred in the Early Oligocene. Late Oligocene mysticetes vary considerably in jaw form and kinesis, tooth form and function, and development of baleen, implying a wide range of raptorial, suctorial and filter-feeding behaviour. More study may elucidate the function of jaws, teeth and baleen in terms of opportunist/generalist feeding, as in modern gray whales, versus specialized feeding. We here propose that early mysticetes, when transitioned from toothed to baleen-bearing, were generalists and opportunists instead of specializing in any forms of feeding strategies. In addition, two different phylogenetic analyses placed (dagger)Toipahautea either in a polytomy including crown Mysticeti, or immediately basal to the crown, and above (dagger)Eomysticetidae in both cases. Because the (dagger)Toipahautea waitaki holotype is an immature individual, it may plot more basally in phylogeny than its true position.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.6
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据