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Tsai CH, Goedert JL, Boessenecker RW. The oldest mysticete in the Northern Hemisphere. Curr Biol 2024; 34:1794-1800.e3. [PMID: 38552627 DOI: 10.1016/j.cub.2024.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Revised: 02/27/2024] [Accepted: 03/08/2024] [Indexed: 04/25/2024]
Abstract
Extant baleen whales (Mysticeti) uniquely use keratinous baleen for filter-feeding and lack dentition, but the fossil record clearly shows that "toothed" baleen whales first appeared in the Late Eocene.1 Globally, only two Eocene mysticetes have been found, and both are from the Southern Hemisphere: Mystacodon selenensis from Peru, 36.4 mega-annum (Ma) ago1,2 and Llanocetus denticrenatus from Antarctica, 34.2 Ma ago.3,4 Based on a partial skull from the lower part of the Lincoln Creek Formation in Washington State, USA, we describe the Northern Hemisphere's geochronologically earliest mysticete, Fucaia humilis sp. nov. Geology, biostratigraphy, and magnetostratigraphy places Fucaia humilis sp. nov. in the latest Eocene (ca. 34.5 Ma ago, near the Eocene/Oligocene transition at 33.9 Ma ago), approximately coeval with the oldest record of fossil kelps, also in the northeastern Pacific.5 This observation leads to our hypothesis that the origin and development of a relatively stable, nutrient-rich kelp ecosystem5,6 in the latest Eocene may have fostered the radiation of small-sized toothed mysticetes (Family Aetiocetidae) in the North Pacific basin, a stark contrast to the larger Llanocetidae (whether Mystacodon belongs to llanocetids or another independent clade remains unresolved) with the latest Eocene onset of the Antarctic Circumpolar Current in the Southern Hemisphere.7,8,9 Our discovery suggests that disparate mechanisms and ecological scenarios may have nurtured contrasting early mysticete evolutionary histories in the Northern and Southern hemispheres.
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Affiliation(s)
- Cheng-Hsiu Tsai
- Department of Life Science and Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei 10617, Taiwan; Department of Geology, National Museum of Nature and Science, Tsukuba 305-0005, Japan.
| | - James L Goedert
- Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98105, USA.
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2
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López‐Martínez AM, Magallón S, von Balthazar M, Schönenberger J, Sauquet H, Chartier M. Angiosperm flowers reached their highest morphological diversity early in their evolutionary history. THE NEW PHYTOLOGIST 2024; 241:1348-1360. [PMID: 38029781 PMCID: PMC10952840 DOI: 10.1111/nph.19389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 10/20/2023] [Indexed: 12/01/2023]
Abstract
Flowers are the complex and highly diverse reproductive structures of angiosperms. Because of their role in sexual reproduction, the evolution of flowers is tightly linked to angiosperm speciation and diversification. Accordingly, the quantification of floral morphological diversity (disparity) among angiosperm subgroups and through time may give important insights into the evolutionary history of angiosperms as a whole. Based on a comprehensive dataset focusing on 30 characters describing floral structure across angiosperms, we used 1201 extant and 121 fossil flowers to measure floral disparity and explore patterns of floral evolution through time and across lineages. We found that angiosperms reached their highest floral disparity in the Early Cretaceous. However, decreasing disparity toward the present likely has not precluded the innovation of other complex traits at other morphological levels, which likely played a key role in the outstanding angiosperm species richness. Angiosperms occupy specific regions of the theoretical morphospace, indicating that only a portion of the possible floral trait combinations is observed in nature. The ANA grade, the magnoliids, and the early-eudicot grade occupy large areas of the morphospace (higher disparity), whereas nested groups occupy narrower regions (lower disparity).
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Affiliation(s)
- Andrea M. López‐Martínez
- Posgrado en Ciencias Biológicas, Instituto de BiologíaUniversidad Nacional Autónoma de México, 3er Circuito de Ciudad UniversitariaCoyoacánCiudad de México04510Mexico
- Departamento de Botánica, Instituto de BiologíaUniversidad Nacional Autónoma de México, 3er Circuito de Ciudad UniversitariaCoyoacánCiudad de México04510Mexico
| | - Susana Magallón
- Departamento de Botánica, Instituto de BiologíaUniversidad Nacional Autónoma de México, 3er Circuito de Ciudad UniversitariaCoyoacánCiudad de México04510Mexico
| | - Maria von Balthazar
- Department of Botany and Biodiversity ResearchUniversity of ViennaRennweg 14ViennaA‐1030Austria
| | - Jürg Schönenberger
- Department of Botany and Biodiversity ResearchUniversity of ViennaRennweg 14ViennaA‐1030Austria
| | - Hervé Sauquet
- National Herbarium of New South Wales (NSW)Royal Botanic Gardens and Domain TrustSydneyNSW2000Australia
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental SciencesUniversity of New South Wales, Biological Sciences North (D26)SydneyNSW2052Australia
| | - Marion Chartier
- Department of Botany and Biodiversity ResearchUniversity of ViennaRennweg 14ViennaA‐1030Austria
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3
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Coombs EJ, Knapp A, Park T, Bennion RF, McCurry MR, Lanzetti A, Boessenecker RW, McGowen MR. Drivers of morphological evolution in the toothed whale jaw. Curr Biol 2024; 34:273-285.e3. [PMID: 38118449 DOI: 10.1016/j.cub.2023.11.056] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 11/20/2023] [Accepted: 11/27/2023] [Indexed: 12/22/2023]
Abstract
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.
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Affiliation(s)
- Ellen J Coombs
- 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.
| | - Andrew Knapp
- Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK; University College London, Gower Street, London WC1E 6BT, UK
| | - Travis Park
- Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK; School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia
| | - Rebecca F Bennion
- 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
| | - Matthew R McCurry
- 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
| | - Agnese Lanzetti
- 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
| | - Robert W Boessenecker
- University of California Museum of Paleontology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Michael R McGowen
- Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, 10th St & Constitution Ave NW, Washington, DC 20560, USA
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4
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Racicot R, Smith C. Cetology: The bare 'jaw' bones of whale evolution. Curr Biol 2024; 34:R67-R69. [PMID: 38262363 DOI: 10.1016/j.cub.2023.12.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Whale jaws are essential for both feeding and underwater hearing since the earliest 'walking' whales returned to the oceans. Over ∼50 million years of subsequent evolution have morphed the whale jaw into extreme shapes, but the hearing region remains conserved due to its critical acoustic functions.
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Affiliation(s)
- Rachel Racicot
- Department of Messel Research and Mammalogy, Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, 60325 Frankfurt am Main, Germany.
| | - Chris Smith
- Division of Anthropology, American Museum of Natural History, 79(th) Street at Central Park West, New York, NY 10024, USA; New York Consortium in Evolutionary Primatology, New York, NY 10024, USA
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5
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Goswami A, Noirault E, Coombs EJ, Clavel J, Fabre AC, Halliday TJD, Churchill M, Curtis A, Watanabe A, Simmons NB, Beatty BL, Geisler JH, Fox DL, Felice RN. Developmental origin underlies evolutionary rate variation across the placental skull. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220083. [PMID: 37183904 PMCID: PMC10184245 DOI: 10.1098/rstb.2022.0083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
The placental skull has evolved into myriad forms, from longirostrine whales to globular primates, and with a diverse array of appendages from antlers to tusks. This disparity has recently been studied from the perspective of the whole skull, but the skull is composed of numerous elements that have distinct developmental origins and varied functions. Here, we assess the evolution of the skull's major skeletal elements, decomposed into 17 individual regions. Using a high-dimensional morphometric approach for a dataset of 322 living and extinct eutherians (placental mammals and their stem relatives), we quantify patterns of variation and estimate phylogenetic, allometric and ecological signal across the skull. We further compare rates of evolution across ecological categories and ordinal-level clades and reconstruct rates of evolution along lineages and through time to assess whether developmental origin or function discriminate the evolutionary trajectories of individual cranial elements. Our results demonstrate distinct macroevolutionary patterns across cranial elements that reflect the ecological adaptations of major clades. Elements derived from neural crest show the fastest rates of evolution, but ecological signal is equally pronounced in bones derived from neural crest and paraxial mesoderm, suggesting that developmental origin may influence evolutionary tempo, but not capacity for specialisation. This article is part of the theme issue 'The mammalian skull: development, structure and function'.
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Affiliation(s)
- Anjali Goswami
- Department of Life Sciences, Natural History Museum, London SW7 5BD, UK
- Department of Genetics, Evolution, and Environment, University College London, London WC1E 6BT, UK
| | - Eve Noirault
- Department of Life Sciences, Natural History Museum, London SW7 5BD, UK
| | - Ellen J Coombs
- Department of Life Sciences, Natural History Museum, London SW7 5BD, UK
- Department of Genetics, Evolution, and Environment, University College London, London WC1E 6BT, UK
- Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA
| | - Julien Clavel
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR 5023 LEHNA, 69622 Villeurbanne, France
| | - Anne-Claire Fabre
- Department of Life Sciences, Natural History Museum, London SW7 5BD, UK
- Naturhistorisches Museum Bern, 3005 Bern, Switzerland
- Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland
| | - Thomas J D Halliday
- Department of Life Sciences, Natural History Museum, London SW7 5BD, UK
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Morgan Churchill
- Department of Biology, University of Wisconsin Oshkosh, Oshkosh, WI 54901, USA
| | - Abigail Curtis
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Akinobu Watanabe
- Department of Life Sciences, Natural History Museum, London SW7 5BD, UK
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA
- Division of Paleontology, American Museum of Natural History, New York, NY 10024, USA
| | - Nancy B Simmons
- Department of Mammalogy, Division of Vertebrate Zoology, American Museum of Natural History, New York, NY 10024, USA
| | - Brian L Beatty
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA
| | - Jonathan H Geisler
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA
| | - David L Fox
- Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Ryan N Felice
- Department of Life Sciences, Natural History Museum, London SW7 5BD, UK
- Department of Genetics, Evolution, and Environment, University College London, London WC1E 6BT, UK
- Centre for Integrative Anatomy, Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
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6
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Roston RA, Boessenecker RW, Geisler JH. Evolution and development of the cetacean skull roof: a case study in novelty and homology. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220086. [PMID: 37183892 PMCID: PMC10184229 DOI: 10.1098/rstb.2022.0086] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 11/15/2022] [Indexed: 05/16/2023] Open
Abstract
Skulls of living whales and dolphins (cetaceans) are telescoped-bones of the skull roof are overlapped by expanded facial bones and/or anteriorly extended occipital bones. Evolution of the underlying skull roof (calvarium), which lies between the telescoped regions, is relatively unstudied. We explore the evolution and development of the calvarium of toothed whales (odontocetes) by integrating fetal data with Oligocene odontocete fossils from North America, including eight neonatal and juvenile skulls of Olympicetus†. We identified two potential synapomorphies of crown Cetacea: contact of interparietals with frontals, and a single anterior median interparietal (AMI) element. Within Odontoceti, loss of contact between the parietals diagnoses the clade including Delphinida, Ziphiidae and Platanistidae (=Synrhina). Delphinida is characterized by a greatly enlarged interparietal. New fetal series of delphinoids reveal a consistent developmental pattern with three elements: the AMI and bilateral posterior interparietals (PIs). The PIs most resemble the medial interparietal elements of terrestrial artiodactyls, suggesting that the AMI of cetaceans could be a unique ossification. More broadly, the paucity of conserved anatomical relationships of the interparietals, as well as the fact that the elements often do not coalesce into a single bone, demonstrates that assessing homology of the interparietals across mammals remains challenging. This article is part of the theme issue 'The mammalian skull: development, structure and function'.
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Affiliation(s)
- R. A. Roston
- Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA 98195, USA
- Center for Developmental Biology and Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - R. W. Boessenecker
- Department of Geology and Environmental Geosciences, College of Charleston, Charleston, SC 29424, USA
- University of California Museum of Paleontology, University of California, Berkeley, CA 94720, USA
| | - J. H. Geisler
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA
- Department of Paleobiology, National Museum of Natural History, Washington, DC 20560, USA
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7
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White HE, Tucker AS, Fernandez V, Portela Miguez R, Hautier L, Herrel A, Urban DJ, Sears KE, Goswami A. Pedomorphosis in the ancestry of marsupial mammals. Curr Biol 2023:S0960-9822(23)00457-8. [PMID: 37119816 DOI: 10.1016/j.cub.2023.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 02/27/2023] [Accepted: 04/05/2023] [Indexed: 05/01/2023]
Abstract
Within mammals, different reproductive strategies (e.g., egg laying, live birth of extremely underdeveloped young, and live birth of well-developed young) have been linked to divergent evolutionary histories. How and when developmental variation across mammals arose is unclear. While egg laying is unquestionably considered the ancestral state for all mammals, many long-standing biases treat the extreme underdeveloped state of marsupial young as the ancestral state for therian mammals (clade including both marsupials and placentals), with the well-developed young of placentals often considered the derived mode of development. Here, we quantify mammalian cranial morphological development and estimate ancestral patterns of cranial shape development using geometric morphometric analysis of the largest comparative ontogenetic dataset of mammals to date (165 specimens, 22 species). We identify a conserved region of cranial morphospace for fetal specimens, after which cranial morphology diversified through ontogeny in a cone-shaped pattern. This cone-shaped pattern of development distinctively reflected the upper half of the developmental hourglass model. Moreover, cranial morphological variation was found to be significantly associated with the level of development (position on the altricial-precocial spectrum) exhibited at birth. Estimation of ancestral state allometry (size-related shape change) reconstructs marsupials as pedomorphic relative to the ancestral therian mammal. In contrast, the estimated allometries for the ancestral placental and ancestral therian were indistinguishable. Thus, from our results, we hypothesize that placental mammal cranial development most closely reflects that of the ancestral therian mammal, while marsupial cranial development represents a more derived mode of mammalian development, in stark contrast to many interpretations of mammalian evolution.
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Affiliation(s)
- Heather E White
- Science Department, Natural History Museum, Cromwell Road, London SW7 5BD, UK; Centre for Craniofacial and Regenerative Biology, King's College London, Great Maze Pond, London SE1 9RT, UK; Division of Biosciences, University College London, Gower Street, London WC1E 6DE, UK.
| | - Abigail S Tucker
- Centre for Craniofacial and Regenerative Biology, King's College London, Great Maze Pond, London SE1 9RT, UK
| | - Vincent Fernandez
- European Synchrotron Radiation Facility, 71 rue des Martyrs, 38000 Grenoble, France
| | | | - Lionel Hautier
- Science Department, Natural History Museum, Cromwell Road, London SW7 5BD, UK; Institut des Sciences de l'Evolution, Université de Montpellier, CNRS, IRD, EPHE, Montpellier 34095, France
| | - Anthony Herrel
- UMR 7179, Centre National de la Recherche Scientifique/Muséum National d'Histoire Naturelle, Département Adaptations du Vivant, 55 rue Buffon, 75005 Paris, France
| | - Daniel J Urban
- Institute of Genomic Biology, University of Illinois, Urbana, IL 61801, USA
| | - Karen E Sears
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Anjali Goswami
- Science Department, Natural History Museum, Cromwell Road, London SW7 5BD, UK; Division of Biosciences, University College London, Gower Street, London WC1E 6DE, UK
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8
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Burin G, Park T, James TD, Slater GJ, Cooper N. The dynamic adaptive landscape of cetacean body size. Curr Biol 2023; 33:1787-1794.e3. [PMID: 36990088 DOI: 10.1016/j.cub.2023.03.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 10/28/2022] [Accepted: 03/06/2023] [Indexed: 03/30/2023]
Abstract
Adaptive landscapes are central to evolutionary theory, forming a conceptual bridge between micro- and macroevolution.1,2,3,4 Evolution by natural selection across an adaptive landscape should drive lineages toward fitness peaks, shaping the distribution of phenotypic variation within and among clades over evolutionary timescales.5 The location and breadth of these peaks in phenotypic space can also evolve,4 but whether phylogenetic comparative methods can detect such patterns has largely remained unexplored.6 Here, we characterize the global and local adaptive landscape for total body length in cetaceans (whales, dolphins, and relatives), a trait that spans 5 orders of magnitude, across their ∼53 million year evolutionary history. Using phylogenetic comparative methods, we analyze shifts in long-term mean body length7 and directional changes in average trait values8 for 345 living and fossil cetacean taxa. Remarkably, we find that the global macroevolutionary adaptive landscape of cetacean body length is relatively flat, with very few peak shifts occurring after cetaceans entered the oceans. Local peaks are more numerous and manifest as trends along branches linked to specific adaptations. These results contrast with previous studies using only extant taxa,9 highlighting the vital role of fossil data for understanding macroevolution.10,11,12 Our results indicate that adaptive peaks are dynamic and are associated with subzones of local adaptations, creating moving targets for species adaptation. In addition, we identify limits in our ability to detect some evolutionary patterns and processes and suggest that multiple approaches are required to characterize complex hierarchical patterns of adaptation in deep time.
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9
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Ecomorphology of toothed whales (Cetacea, Odontoceti) as revealed by 3D skull geometry. J MAMM EVOL 2023. [DOI: 10.1007/s10914-022-09642-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
AbstractExtant odontocetes (toothed whales) exhibit differences in body size and brain mass, biosonar mode, feeding strategies, and diving and habitat adaptations. Strong selective pressures associated with these factors have likely contributed to the morphological diversification of their skull. Here, we used 3D landmark geometric morphometric data from the skulls of 60 out of ~ 72 extant odontocete species and a well-supported phylogenetic tree to test whether size and shape variation are associated with ecological adaptations at an interspecific scale. Odontocete skull morphology exhibited a significant phylogenetic signal, with skull size showing stronger signal than shape. After accounting for phylogeny, significant associations were detected between skull size and biosonar mode, body length, brain and body mass, maximum and minimum prey size, and maximum peak frequency. Brain mass was also strongly correlated with skull shape together with surface temperature and average and minimum prey size. When asymmetric and symmetric components of shape were analysed separately, a significant correlation was detected between sea surface temperature and both symmetric and asymmetric components of skull shape, and between diving ecology and the asymmetric component. Skull shape variation of odontocetes was strongly influenced by evolutionary allometry but most of the associations with ecological variables were not supported after phylogenetic correction. This suggests that ecomorphological feeding adaptations vary more between, rather than within, odontocete families, and functional anatomical patterns across odontocete clades are canalised by size constraints.
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10
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Meloro C. Evolution: The shape of cetacean skulls through deep time. Curr Biol 2022; 32:R457-R459. [PMID: 35609540 DOI: 10.1016/j.cub.2022.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Cetaceans (comprising whales, dolphins and porpoises) adapted towards a fully aquatic lifestyle. These adaptations are especially evident in their skulls. Based on a rich sample of fossil and extant cetacean skulls, a new study identifies links between shape changes and ecological specialisation through deep time.
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Affiliation(s)
- Carlo Meloro
- Research Centre in Evolutionary Anthropology and Palaeoecology, School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, UK.
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