1
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Kang H, Liu Q, Seim I, Zhang W, Li H, Gao H, Lin W, Lin M, Zhang P, Zhang Y, Gao H, Wang Y, Qin Y, Liu M, Dong L, Yang Z, Zhang Y, Han L, Fan G, Li S. A genome and single-nucleus cerebral cortex transcriptome atlas of the short-finned pilot whale Globicephala macrorhynchus. Mol Ecol Resour 2023. [PMID: 36826393 DOI: 10.1111/1755-0998.13775] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 02/09/2023] [Accepted: 02/22/2023] [Indexed: 02/25/2023]
Abstract
Cetaceans (dolphins, whales, and porpoises) have large and anatomically sophisticated brains. To expand our understanding of the cellular makeup of cetacean brains and the similarities and divergence between the brains of cetaceans and terrestrial mammals, we report a short-finned pilot whale (Globicephala macrorhynchus) single-nucleus transcriptome atlas. To achieve this goal, we assembled a chromosome-scale reference genome spanning 2.25 Gb on 22 chromosomes and profiled the gene expression of five major anatomical cortical regions of the short-finned pilot whale by single-nucleus RNA-sequencing (snRNA-seq). We identified six major cell lineages in the cerebral cortex (excitatory neurons, inhibitory neurons, oligodendrocytes, oligodendrocyte precursor cells, astrocytes, and endothelial cells), eight molecularly distinct subclusters of excitatory neurons, and four subclusters of inhibitory neurons. Finally, a comparison of snRNA-seq data from the short-finned pilot whale, human, and rhesus macaque revealed a broadly conserved cellular makeup of brain cell types. Our study provides genomic resources and molecular insights into cetacean brain evolution.
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Affiliation(s)
- Hui Kang
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Qun Liu
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China.,Lars Bolund Institute of Regenerative Medicine, Qingdao-Europe Advanced Institute for Life Sciences, BGI-Qingdao, Qingdao, China.,Department of Biology, University of Copenhagen, Copenhagen, Denmark.,Qingdao Key Laboratory of Marine Genomics, BGI-Qingdao, Qingdao, China
| | - Inge Seim
- Integrative Biology Laboratory, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Wenwei Zhang
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, China
| | - Hanbo Li
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China.,Lars Bolund Institute of Regenerative Medicine, Qingdao-Europe Advanced Institute for Life Sciences, BGI-Qingdao, Qingdao, China
| | - Haiyu Gao
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Wenzhi Lin
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Mingli Lin
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Peijun Zhang
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | | | | | - Yang Wang
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China
| | - Yating Qin
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China
| | - Mingming Liu
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Lijun Dong
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Zixin Yang
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | | | - Lei Han
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, China
| | - Guangyi Fan
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China.,State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, China
| | - Songhai Li
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
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2
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Lanzetti A, Coombs EJ, Portela Miguez R, Fernandez V, Goswami A. The ontogeny of asymmetry in echolocating whales. Proc Biol Sci 2022; 289:20221090. [PMID: 35919995 PMCID: PMC9346347 DOI: 10.1098/rspb.2022.1090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 07/12/2022] [Indexed: 12/14/2022] Open
Abstract
Extreme asymmetry of the skull is one of the most distinctive traits that characterizes toothed whales (Odontoceti, Cetacea). The origin and function of cranial asymmetry are connected to the evolution of echolocation, the ability to use high-frequency sounds to navigate the surrounding environment. Although this novel phenotype must arise through changes in cranial development, the ontogeny of cetacean asymmetry has never been investigated. Here we use three-dimensional geometric morphometrics to quantify the changes in degree of asymmetry and skull shape during prenatal and postnatal ontogeny for five genera spanning odontocete diversity (oceanic dolphins, porpoises and beluga). Asymmetry in early ontogeny starts low and tracks phylogenetic relatedness of taxa. Distantly related taxa that share aspects of their ecology overwrite these initial differences via heterochronic shifts, ultimately converging on comparable high levels of skull asymmetry. Porpoises maintain low levels of asymmetry into maturity and present a decelerated rate of growth, probably retained from the ancestral condition. Ancestral state reconstruction of allometric trajectories demonstrates that both paedomorphism and peramorphism contribute to cranial shape diversity across odontocetes. This study provides a striking example of how divergent developmental pathways can produce convergent ecological adaptations, even for some of the most unusual phenotypes exhibited among vertebrates.
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Affiliation(s)
- Agnese Lanzetti
- Department of Life Sciences, Natural History Museum, Cromwell Road, Kensington, London SW7 5BD, UK
| | - Ellen J. Coombs
- Department of Vertebrate Zoology, Smithsonian National Museum of Natural History, PO Box 37012, MRC 108, Washington, DC 20013-7012, USA
| | - Roberto Portela Miguez
- Department of Life Sciences, Natural History Museum, Cromwell Road, Kensington, London SW7 5BD, UK
| | | | - Anjali Goswami
- Department of Life Sciences, Natural History Museum, Cromwell Road, Kensington, London SW7 5BD, UK
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3
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Racicot R. Evolution of whale sensory ecology: Frontiers in nondestructive anatomical investigations. Anat Rec (Hoboken) 2021; 305:736-752. [PMID: 34546007 DOI: 10.1002/ar.24761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 06/09/2021] [Accepted: 07/14/2021] [Indexed: 12/18/2022]
Abstract
Studies surrounding the evolution of sensory system anatomy in cetaceans over the last ~100 years have shed light on aspects of the early evolution of hearing sensitivities, the small relative size of the organ of balance (semicircular canals and vestibule), brain (endocast) shape and relative volume changes, and ontogenetic development of sensory-related structures. Here, I review advances in our knowledge of sensory system anatomy as informed by the use of nondestructive imaging techniques, with a focus on applied methods in computed tomography (CT and μCT), and identify the key questions that remain to be addressed. Of these, the most important are: Is lower frequency hearing sensitivity the ancestral condition for whales? Did echolocation evolve more than once in odontocetes; and if so, when and why? How has the structure of the cetacean brain changed, through the evolution of whales, and does this correspond to changes in hearing sensitivities? Finally, what are the general pathways of ontogenetic development of sensory systems in odontocetes and mysticetes? Answering these questions will allow us to understand important macroevolutionary patterns in a fully aquatic mammalian group and provides baseline data on species for which we have limited biological information because of logistical limitations.
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Affiliation(s)
- Rachel Racicot
- Abteilung Messelforschung und Mammalogie, Senckenberg Forschungsinstitut und Naturkundemuseum, Frankfurt am Main, Germany.,Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
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4
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Groves SL, Peredo CM, Pyenson ND. What are the limits on whale ear bone size? Non-isometric scaling of the cetacean bulla. PeerJ 2021; 9:e10882. [PMID: 33604200 PMCID: PMC7869665 DOI: 10.7717/peerj.10882] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 01/11/2021] [Indexed: 02/02/2023] Open
Abstract
The history of cetaceans demonstrates dramatic macroevolutionary changes that have aided their transformation from terrestrial to obligate aquatic mammals. Their fossil record shows extensive anatomical modifications that facilitate life in a marine environment. To better understand the constraints on this transition, we examined the physical dimensions of the bony auditory complex, in relation to body size, for both living and extinct cetaceans. We compared the dimensions of the tympanic bulla, a conch-shaped ear bone unique to cetaceans, with bizygomatic width—a proxy for cetacean body size. Our results demonstrate that cetacean ears scale non-isometrically with body size, with about 70% of variation explained by increases in bizygomatic width. Our results, which encompass the breadth of the whale fossil record, size diversity, and taxonomic distribution, suggest that functional auditory capacity is constrained by congruent factors related to cranial morphology, as opposed to allometrically scaling with body size.
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Affiliation(s)
- Sabrina L Groves
- Department of Paleobiology, National Museum of Natural History, Washington, DC, USA.,Department of Biological Sciences, Mount Holyoke College, South Hadley, MA, USA
| | - Carlos Mauricio Peredo
- Department of Paleobiology, National Museum of Natural History, Washington, DC, USA.,Department of Earth and Environmental Science, University of Michigan - Ann Arbor, Ann Arbor, MI, USA.,Department of Marine Biology, Texas A&M University - Galveston, Galveston, TX, USA
| | - Nicholas D Pyenson
- Department of Paleobiology, National Museum of Natural History, Washington, DC, USA.,Department of Paleontology and Geology, Burke Museum of Natural History and Culture, Seattle, WA, USA
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5
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Ichishima H, Kawabe S, Sawamura H. The so-called foramen singulare in cetacean periotics is actually the superior vestibular area. Anat Rec (Hoboken) 2021; 304:1792-1799. [PMID: 33432669 DOI: 10.1002/ar.24585] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/12/2020] [Accepted: 12/17/2020] [Indexed: 11/10/2022]
Abstract
It is nearly 100 years ago that the "foramen singulare" was first identified in cetacean periotics. Since then, the "foramen singulare" has been recognized in periotics of many cetacean species, extant or extinct. Surprisingly, however, it has never been confirmed if the foramen singulare in cetacean periotics is really homologous to that in other mammals. It is known that in mammals including humans the posterior ampullary nerve, which innervates the posterior semicircular duct, passes through the foramen singulare. We use an X-ray micro-CT scan to examine endocasts of the bony labyrinth of the inner ear of cetacean periotics, showing that the osseous canal extending from the so-called foramen singulare goes toward the anterior bony ampulla, meaning that the alleged foramen singulare in cetacean periotics is really the superior vestibular area, through which the utriculoampullary nerve enters. The transverse crest is quite significant to identify each quadrant of the fundus of the internal acoustic meatus, but in many cetacean species the transverse crest is poorly developed, almost imperceptible in some species, and this could have brought confusion into the interpretation over the superior vestibular area and the foramen singulare. The bony septum separating the cerebral aperture of the facial canal from the foramen singulare is not the transverse crest, but the perpendicular crest. The foramen singulare is not a distinct foramen separated from the inferior vestibular area. Instead, the true foramen singulare opens near the inferior vestibular area in the internal acoustic meatus in cetacean periotics.
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Affiliation(s)
| | - Soichiro Kawabe
- Institute of Dinosaur Research, Fukui Prefectural University, Eiheiji, Fukui, Japan
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6
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Bisconti M, Damarco P, Tartarelli G, Pavia M, Carnevale G. A natural endocast of an early Miocene odontocete and its implications in cetacean brain evolution. J Comp Neurol 2020; 529:1198-1227. [PMID: 32840887 DOI: 10.1002/cne.25015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 08/14/2020] [Accepted: 08/17/2020] [Indexed: 12/18/2022]
Abstract
The natural endocast Museo di Geologia e Paleontologia of the Università degli Studi di Torino (MGPT)-PU 13873 is described and analyzed in order to interpret its taxonomic affinities and its potential significance on our understanding of cetacean brain evolution. The endocast is from the early Miocene of Piedmont (between ca. 19 and 16 million years ago), Northwestern Italy, and shows a number of plesiomorphic characters. These include: scarcely rounded cerebral hemispheres, cerebellum exposed in dorsal view with little superimposition by the cerebral hemispheres, short temporal lobe, and long sylvian fissure. The distance between the hypophysis and the rostral pons is particularly high, as it was determined by the calculus of the hypothalamus quotient, suggesting that the development of a deep interpeduncular fossa was not as advanced as in living odontocetes. The encephalization quotient (EQ) of MGPT-PU 13873 is ~1.81; therefore, this specimen shows an EQ in line with other fossil whales of the same geological age (early Miocene). Comparative analysis shows that there is a critical lack of data from the late Miocene and Pliocene that prevents us to fully understand the recent evolution of the EQ diversity in whales. Moreover, the past diversity of brain size and shape in mysticetes is virtually unknown. All these observations point to the need of additional efforts to uncover evolutionary patterns and processes on cetacean brain evolution.
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Affiliation(s)
- Michelangelo Bisconti
- Dipartimento di Scienze della Terra, Università degli Studi di Torino, Torino, Italy.,San Diego Natural History Museum, San Diego, California, USA
| | - Piero Damarco
- Ente di Gestione del Parco Paleontologico Astigiano, Museo Paleontologico Territoriale dell'Astigiano, Asti, Italy
| | | | - Marco Pavia
- Dipartimento di Scienze della Terra, Università degli Studi di Torino, Torino, Italy.,Museo di Geologia e Paleontologia, Università degli Studi di Torino, Torino, Italy
| | - Giorgio Carnevale
- Dipartimento di Scienze della Terra, Università degli Studi di Torino, Torino, Italy
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7
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Coombs EJ, Clavel J, Park T, Churchill M, Goswami A. Wonky whales: the evolution of cranial asymmetry in cetaceans. BMC Biol 2020; 18:86. [PMID: 32646447 PMCID: PMC7350770 DOI: 10.1186/s12915-020-00805-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 06/01/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Unlike most mammals, toothed whale (Odontoceti) skulls lack symmetry in the nasal and facial (nasofacial) region. This asymmetry is hypothesised to relate to echolocation, which may have evolved in the earliest diverging odontocetes. Early cetaceans (whales, dolphins, and porpoises) such as archaeocetes, namely the protocetids and basilosaurids, have asymmetric rostra, but it is unclear when nasofacial asymmetry evolved during the transition from archaeocetes to modern whales. We used three-dimensional geometric morphometrics and phylogenetic comparative methods to reconstruct the evolution of asymmetry in the skulls of 162 living and extinct cetaceans over 50 million years. RESULTS In archaeocetes, we found asymmetry is prevalent in the rostrum and also in the squamosal, jugal, and orbit, possibly reflecting preservational deformation. Asymmetry in odontocetes is predominant in the nasofacial region. Mysticetes (baleen whales) show symmetry similar to terrestrial artiodactyls such as bovines. The first significant shift in asymmetry occurred in the stem odontocete family Xenorophidae during the Early Oligocene. Further increases in asymmetry occur in the physeteroids in the Late Oligocene, Squalodelphinidae and Platanistidae in the Late Oligocene/Early Miocene, and in the Monodontidae in the Late Miocene/Early Pliocene. Additional episodes of rapid change in odontocete skull asymmetry were found in the Mid-Late Oligocene, a period of rapid evolution and diversification. No high-probability increases or jumps in asymmetry were found in mysticetes or archaeocetes. Unexpectedly, no increases in asymmetry were recovered within the highly asymmetric ziphiids, which may result from the extreme, asymmetric shape of premaxillary crests in these taxa not being captured by landmarks alone. CONCLUSIONS Early ancestors of living whales had little cranial asymmetry and likely were not able to echolocate. Archaeocetes display high levels of asymmetry in the rostrum, potentially related to directional hearing, which is lost in early neocetes-the taxon including the most recent common ancestor of living cetaceans. Nasofacial asymmetry becomes a significant feature of Odontoceti skulls in the Early Oligocene, reaching its highest levels in extant taxa. Separate evolutionary regimes are reconstructed for odontocetes living in acoustically complex environments, suggesting that these niches impose strong selective pressure on echolocation ability and thus increased cranial asymmetry.
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Affiliation(s)
- Ellen J Coombs
- Genetics, Evolution, and Environment Department, University College London, Gower Street, London, WC1E 6BT, UK.
- Department of Life Sciences, Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK.
| | - Julien Clavel
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR 5023 LEHNA, F-69622, Villeurbanne, France
| | - Travis Park
- Department of Life Sciences, Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK
- Department of Earth Sciences, University of Oxford, Oxford, OX1 3AN, UK
| | - Morgan Churchill
- Department of Biology, University of Wisconsin-Oshkosh, Oshkosh, WI, 54901, USA
| | - Anjali Goswami
- Genetics, Evolution, and Environment Department, University College London, Gower Street, London, WC1E 6BT, UK
- Department of Life Sciences, Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK
- Department of Earth Sciences, University College London, Gower Street, London, WC1E 6BT, UK
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8
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Martins MCI, Park T, Racicot R, Cooper N. Intraspecific variation in the cochleae of harbour porpoises (Phocoena phocoena) and its implications for comparative studies across odontocetes. PeerJ 2020; 8:e8916. [PMID: 32322439 PMCID: PMC7161573 DOI: 10.7717/peerj.8916] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 03/15/2020] [Indexed: 12/19/2022] Open
Abstract
In morphological traits, variation within species is generally considered to be lower than variation among species, although this assumption is rarely tested. This is particularly important in fields like palaeontology, where it is common to use a single individual as representative of a species due to the rarity of fossils. Here, we investigated intraspecific variation in the cochleae of harbour porpoises (Phocoena phocoena). Interspecific variation of cochlear morphology is well characterised among odontocetes (toothed whales) because of the importance of the structure in echolocation, but generally these studies use only a single cochlea to represent each species. In this study we compare variation within the cochleae of 18 specimens of P. phocoena with variations in cochlear morphology across 51 other odontocete species. Using both 3D landmark and linear measurement data, we performed Generalised Procrustes and principal component analyses to quantify shape variation. We then quantified intraspecific variation in our sample of P. phocoena by estimating disparity and the coefficient of variation for our 3D and linear data respectively. Finally, to determine whether intraspecific variation may confound the results of studies of interspecific variation, we used multivariate and univariate analyses of variance to test whether variation within the specimens of P. phocoena was significantly lower than that across odontocetes. We found low levels of intraspecific variation in the cochleae of P. phocoena, and that cochlear shape within P. phocoena was significantly less variable than across odontocetes. Although future studies should attempt to use multiple cochleae for every species, our results suggest that using just one cochlea for each species should not strongly influence the conclusions of comparative studies if our results are consistent across Cetacea.
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Affiliation(s)
- Maria Clara Iruzun Martins
- Division of Biosciences, University College London, University of London, London, United Kingdom.,Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Travis Park
- Department of Life Sciences, Natural History Museum, London, United Kingdom.,Department of Earth Sciences, University of Oxford, Oxford, United Kingdom
| | - Rachel Racicot
- Forschungsinstitut und Naturkundemuseum, Senckenberg der SNG, Frankfurt am Main, Germany.,The Dinosaur Institute, Natural History Museum of Los Angeles County, Los Angeles, CA, United States of America.,Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, TN, United States of America.,Department of Zoology, Smithsonian Museum of Natural History, Washington, DC, United States of America
| | - Natalie Cooper
- Department of Life Sciences, Natural History Museum, London, United Kingdom
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9
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Racicot RA, Boessenecker RW, Darroch SAF, Geisler JH. Evidence for convergent evolution of ultrasonic hearing in toothed whales (Cetacea: Odontoceti). Biol Lett 2019; 15:20190083. [PMID: 31088283 DOI: 10.1098/rsbl.2019.0083] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Toothed whales (Cetacea: Odontoceti) are the most diverse group of modern cetaceans, originating during the Eocene/Oligocene transition approximately 38 Ma. All extant odontocetes echolocate; a single origin for this behaviour is supported by a unique facial source for ultrasonic vocalizations and a cochlea adapted for hearing the corresponding echoes. The craniofacial and inner ear morphology of Oligocene odontocetes support a rapid (less than 5 Myr) early evolution of echolocation. Although some cranial features in the stem odontocetes Simocetus and Olympicetus suggest an ability to generate ultrasonic sound, until now, the bony labyrinths of taxa of this grade have not been investigated. Here, we use µCT to examine a petrosal of a taxon with clear similarities to Olympicetus avitus. Measurements of the bony labyrinth, when added to an extensive dataset of cetartiodactyls, resulted in this specimen sharing a morphospace with stem whales, suggesting a transitional inner ear. This discovery implies that either the lineage leading to this Olympicetus--like taxon lost the ability to hear ultrasonic sound, or adaptations for ultrasonic hearing evolved twice, once in xenorophids and again on the stem of the odontocete crown group. We favour the latter interpretation as it matches a well-documented convergence of craniofacial morphology between xenorophids and extant odontocetes.
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Affiliation(s)
- Rachel A Racicot
- 1 W.M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges , Claremont, CA 91711 , USA.,2 Vertebrate Paleontology Department and The Dinosaur Institute, Natural History Museum of Los Angeles County , Los Angeles, CA 90007 , USA.,3 Department of Earth and Environmental Sciences, Vanderbilt University , Nashville, TN 37340 , USA
| | - Robert W Boessenecker
- 4 Department of Geology and Environmental Geosciences, College of Charleston , Charleston, SC 29414 , USA
| | - Simon A F Darroch
- 3 Department of Earth and Environmental Sciences, Vanderbilt University , Nashville, TN 37340 , USA
| | - Jonathan H Geisler
- 5 Department of Anatomy, New York Institute of Technology, College of Osteopathic Medicine , Old Westbury, NY 11568 , USA
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10
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Galatius A, Olsen MT, Steeman ME, Racicot RA, Bradshaw CD, Kyhn LA, Miller LA. Raising your voice: evolution of narrow-band high-frequency signals in toothed whales (Odontoceti). Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly194] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Anders Galatius
- Department of Bioscience, Aarhus University, Roskilde, Denmark
| | - Morten Tange Olsen
- Evolutionary Genomics, Natural History Museum of Denmark, University of Copenhagen, Copenhagen O, Denmark
| | | | - Rachel A Racicot
- W. M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, USA
- The Dinosaur Institute, Natural History Museum of Los Angeles County, Los Angeles, CA, USA
- Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, TN, USA
| | - Catherine D Bradshaw
- School of Geographical Sciences, University of Bristol, Bristol, UK
- Met Office Hadley Centre, Exeter, UK
| | - Line A Kyhn
- Department of Bioscience, Aarhus University, Roskilde, Denmark
| | - Lee A Miller
- Department of Biology, University of Southern Denmark, Odense, Denmark
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