Drivers of morphological evolution in the toothed whale jaw.

Autor:	Coombs EJ; Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, 10th St & Constitution Ave NW, Washington, DC 20560, USA; Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK. Electronic address: coombse@si.edu., Knapp A; Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK; University College London, Gower Street, London WC1E 6BT, UK., Park T; Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK; School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia., Bennion RF; Evolution & Diversity Dynamics Lab, Department of Geology, University of Liege, 4000 Liege, Belgium; O.D. Earth and History of Life, Royal Belgian Institute of Natural Sciences, 1000 Brussels, Belgium., McCurry MR; Australian Museum Research Institute, 1 William Street, Sydney, NSW 2010, Australia; Earth & Sustainability Science Research Centre, School of Biological, Earth and Environmental Sciences (BEES), University of New South Wales, Kensington, NSW 2052, Australia; Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20560, USA., Lanzetti A; Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK; School of Geography, Earth, and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK., Boessenecker RW; University of California Museum of Paleontology, University of California, Berkeley, Berkeley, CA 94720, USA., McGowen MR; Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, 10th St & Constitution Ave NW, Washington, DC 20560, USA.
Jazyk:	angličtina
Zdroj:	Current biology : CB [Curr Biol] 2024 Jan 22; Vol. 34 (2), pp. 273-285.e3. Date of Electronic Publication: 2023 Dec 19.
DOI:	10.1016/j.cub.2023.11.056
Abstrakt:	Toothed whales (odontocetes) emit high-frequency underwater sounds (echolocate)-an extreme and unique innovation allowing them to sense their prey and environment. Their highly specialized mandible (lower jaw) allows high-frequency sounds to be transmitted back to the inner ear. Echolocation is evident in the earliest toothed whales, but little research has focused on the evolution of mandibular form regarding this unique adaptation. Here, we use a high-density, three-dimensional geometric morphometric analysis of 100 living and extinct cetacean species spanning their ∼50-million-year evolutionary history. Our analyses demonstrate that most shape variation is found in the relative length of the jaw and the mandibular symphysis. The greatest morphological diversity was obtained during two periods of rapid evolution: the initial evolution of archaeocetes (stem whales) in the early to mid-Eocene as they adapted to an aquatic lifestyle, representing one of the most extreme adaptive transitions known, and later on in the mid-Oligocene odontocetes as they became increasingly specialized for a range of diets facilitated by increasingly refined echolocation. Low disparity in the posterior mandible suggests the shape of the acoustic window, which receives sound, has remained conservative since the advent of directional hearing in the aquatic archaeocetes, even as the earliest odontocetes began to receive sounds from echolocation. Diet, echolocation, feeding method, and dentition type strongly influence mandible shape. Unlike in the toothed whale cranium, we found no significant asymmetry in the mandible. We suggest that a combination of refined echolocation and associated dietary specializations have driven morphology and disparity in the toothed whale mandible. Competing Interests: Declaration of interests The authors declare no competing interests. (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu