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NOTE: THIS ARTICLE IS ESSENTIALLY A HOAX FOR APRIL 1 OF 2014 FOR ASHORO MUSEUM OF PALEONTOLOGY, BUT AIMS TO BE A THOUGHT-PROVOKING PIECE OF WORK TO CONSIDER THE BODY SIZE EVOLUTION IN MYSTICETI (BALEEN WHALES). A Lilliputian whale, Aetiocetus hobbitus Tsai, Cheng-Hsiu Department of Geology, University of Otago, Dunedin, New Zealand Whales (Cetacea: Mysticeti) are the largest animals in the world. As the real Brobdingnagians, how small a whale could be renders an interesting and unresolved biological question. Here I report a smallest whale “produced” at the Ashoro Museum of Paleontology (AMP), Hokkaido, Japan. SYSTEMATIC PALAEONTOLOGY Cetacea Brisson, 1762 Mysticeti Gray, 1864 Aetiocetidae Emlong, 1966 Aetiocetus Emlong, 1966 Aetiocetus hobbitus sp. nov. (FIG. 1) Holotype: AMP0401, including a well-preserved skull and left mandible. Diagnosis: The morphology of AMP0401 is “exactly” the same as Aetiocetus polydentatus, but the size is considerably smaller. The skull length is about 15 cm. Etymology: The species epithet, hobbitus, is latinised from The Hobbit written by J. R. R. Tolkien, describing a fictional, diminutive human species. Aetiocetus hobbitus represents the smallest mysticete species described and named to date. Body size evolution in baleen whales is particularly tantalising and intriguing, since baleen whales are the largest animals to have ever lived on Earth. Given the body size of the earliest known mysticete, Llanocetus denticrenatus, the body size has evolved to both directions in Mysticeti, gigantism: Balaenoptera musculus (blue whale) and dwarfism: Aetiocetus hobbitus sp. nov. (this study). Understanding the underlying evolutionary process that influences the body size evolution in baleen whales in at least two different directions should help decipher the mystery of mysteries – from Lilliputian to Brobdingnagian in baleen whale evolution. Acknowledgements: I thank Hiroshi Sawamura, Tatsuro Ando, and Tatsuya Shinmura for producing and providing this specimen; Yoshihiro Tanaka for helping the research trip in Hokkaido. University of Otago Doctoral Scholarship supports this study. Figure 1. The skull of the holotype of Aetiocetus hobbitus sp. nov. AMP0401. A, dorsal view. B, lateral view. A. B..

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The triple origin of whales DAVID PETERS Independent Researcher 311 Collinsville Avenue, Collinsville, IL 62234, USA [email protected] 314-323-7776 July 13, 2018 RH: PETERS—TRIPLE ORIGIN OF WHALES Keywords: Cetacea, Mysticeti, Odontoceti, Phylogenetic analyis ABSTRACT—Workers presume the traditional whale clade, Cetacea, is monophyletic when they support a hypothesis of relationships for baleen whales (Mysticeti) rooted on stem members of the toothed whale clade (Odontoceti). Here a wider gamut phylogenetic analysis recovers Archaeoceti + Odontoceti far apart from Mysticeti and right whales apart from other mysticetes. The three whale clades had semi-aquatic ancestors with four limbs. The clade Odontoceti arises from a lineage that includes archaeocetids, pakicetids, tenrecs, elephant shrews and anagalids: all predators. The clade Mysticeti arises from a lineage that includes desmostylians, anthracobunids, cambaytheres, hippos and mesonychids: none predators. Right whales are derived from a sister to Desmostylus. Other mysticetes arise from a sister to the RBCM specimen attributed to Behemotops. Basal mysticetes include Caperea (for right whales) and Miocaperea (for all other mysticetes). Cetotheres are not related to aetiocetids. Whales and hippos are not related to artiodactyls. Rather the artiodactyl-type ankle found in basal archaeocetes is also found in the tenrec/odontocete clade. Former mesonychids, Sinonyx and Andrewsarchus, nest close to tenrecs. These are novel observations and hypotheses of mammal interrelationships based on morphology and a wide gamut taxon list that includes relevant taxa that prior studies ignored. Here some taxa are tested together for the first time, so they nest together for the first time. INTRODUCTION Marx and Fordyce (2015) reported the genesis of the baleen whale clade (Mysticeti) extended back to Zygorhiza, Physeter and other toothed whales (Archaeoceti + Odontoceti).
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Mysticetes, Evolution 749
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