1
|
Mitchell DR, Sherratt E, Weisbecker V. Facing the facts: adaptive trade-offs along body size ranges determine mammalian craniofacial scaling. Biol Rev Camb Philos Soc 2024; 99:496-524. [PMID: 38029779 DOI: 10.1111/brv.13032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 11/12/2023] [Accepted: 11/14/2023] [Indexed: 12/01/2023]
Abstract
The mammalian cranium (skull without lower jaw) is representative of mammalian diversity and is thus of particular interest to mammalian biologists across disciplines. One widely retrieved pattern accompanying mammalian cranial diversification is referred to as 'craniofacial evolutionary allometry' (CREA). This posits that adults of larger species, in a group of closely related mammals, tend to have relatively longer faces and smaller braincases. However, no process has been officially suggested to explain this pattern, there are many apparent exceptions, and its predictions potentially conflict with well-established biomechanical principles. Understanding the mechanisms behind CREA and causes for deviations from the pattern therefore has tremendous potential to explain allometry and diversification of the mammalian cranium. Here, we propose an amended framework to characterise the CREA pattern more clearly, in that 'longer faces' can arise through several kinds of evolutionary change, including elongation of the rostrum, retraction of the jaw muscles, or a more narrow or shallow skull, which all result in a generalised gracilisation of the facial skeleton with increased size. We define a standardised workflow to test for the presence of the pattern, using allometric shape predictions derived from geometric morphometrics analysis, and apply this to 22 mammalian families including marsupials, rabbits, rodents, bats, carnivores, antelopes, and whales. Our results show that increasing facial gracility with size is common, but not necessarily as ubiquitous as previously suggested. To address the mechanistic basis for this variation, we then review cranial adaptations for harder biting. These dictate that a more gracile cranium in larger species must represent a structural sacrifice in the ability to produce or withstand harder bites, relative to size. This leads us to propose that facial gracilisation in larger species is often a product of bite force allometry and phylogenetic niche conservatism, where more closely related species tend to exhibit more similar feeding ecology and biting behaviours and, therefore, absolute (size-independent) bite force requirements. Since larger species can produce the same absolute bite forces as smaller species with less effort, we propose that relaxed bite force demands can permit facial gracility in response to bone optimisation and alternative selection pressures. Thus, mammalian facial scaling represents an adaptive by-product of the shifting importance of selective pressures occurring with increased size. A reverse pattern of facial 'shortening' can accordingly also be found, and is retrieved in several cases here, where larger species incorporate novel feeding behaviours involving greater bite forces. We discuss multiple exceptions to a bite force-mediated influence on facial proportions across mammals which lead us to argue that ecomorphological specialisation of the cranium is likely to be the primary driver of facial scaling patterns, with some developmental constraints as possible secondary factors. A potential for larger species to have a wider range of cranial functions when less constrained by bite force demands might also explain why selection for larger sizes seems to be prevalent in some mammalian clades. The interplay between adaptation and constraint across size ranges thus presents an interesting consideration for a mechanistically grounded investigation of mammalian cranial allometry.
Collapse
Affiliation(s)
- D Rex Mitchell
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, South Australia, 5001, Australia
- Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, Wollongong, New South Wales, 2522, Australia
| | - Emma Sherratt
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, 5005, Australia
- South Australian Museum, Adelaide, South Australia, 5000, Australia
| | - Vera Weisbecker
- College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, South Australia, 5001, Australia
- Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, Wollongong, New South Wales, 2522, Australia
| |
Collapse
|
2
|
Farfán-Pira KJ, Martínez-Cuevas TI, Evans TA, Nahmad M. A cis-regulatory sequence of the selector gene vestigial drives the evolution of wing scaling in Drosophila species. J Exp Biol 2023; 226:jeb244692. [PMID: 37078652 PMCID: PMC10234621 DOI: 10.1242/jeb.244692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 04/13/2023] [Indexed: 04/21/2023]
Abstract
Scaling between specific organs and overall body size has long fascinated biologists, being a primary mechanism by which organ shapes evolve. Yet, the genetic mechanisms that underlie the evolution of scaling relationships remain elusive. Here, we compared wing and fore tibia lengths (the latter as a proxy of body size) in Drosophila melanogaster, Drosophila simulans, Drosophila ananassae and Drosophila virilis, and show that the first three of these species have roughly a similar wing-to-tibia scaling behavior. In contrast, D. virilis exhibits much smaller wings relative to their body size compared with the other species and this is reflected in the intercept of the wing-to-tibia allometry. We then asked whether the evolution of this relationship could be explained by changes in a specific cis-regulatory region or enhancer that drives expression of the wing selector gene, vestigial (vg), whose function is broadly conserved in insects and contributes to wing size. To test this hypothesis directly, we used CRISPR/Cas9 to replace the DNA sequence of the predicted Quadrant Enhancer (vgQE) from D. virilis for the corresponding vgQE sequence in the genome of D. melanogaster. Strikingly, we discovered that D. melanogaster flies carrying the D. virilis vgQE sequence have wings that are significantly smaller with respect to controls, partially shifting the intercept of the wing-to-tibia scaling relationship towards that observed in D. virilis. We conclude that a single cis-regulatory element in D. virilis contributes to constraining wing size in this species, supporting the hypothesis that scaling could evolve through genetic variations in cis-regulatory elements.
Collapse
Affiliation(s)
- Keity J. Farfán-Pira
- Department of Physiology, Biophysics and Neurosciences, Centre for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN), Mexico City 07360, Mexico
| | - Teresa I. Martínez-Cuevas
- Department of Physiology, Biophysics and Neurosciences, Centre for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN), Mexico City 07360, Mexico
| | - Timothy A. Evans
- Department of Biological Sciences, University of Arkansas, Fayetteville, AR 72701, USA
| | - Marcos Nahmad
- Department of Physiology, Biophysics and Neurosciences, Centre for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN), Mexico City 07360, Mexico
| |
Collapse
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
Campos-Medina J, Montoya-Sanhueza G, Moreno K, Bostelmann Torrealba E, García M. Paleohistology of Caraguatypotherium munozi (Mammalia, Notoungulata, Mesotheriidae) from the early late Miocene of northern Chile: A preliminary ontogenetic approach. PLoS One 2023; 18:e0273127. [PMID: 36928884 PMCID: PMC10019713 DOI: 10.1371/journal.pone.0273127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 02/24/2023] [Indexed: 03/18/2023] Open
Abstract
The Miocene Caragua fossil fauna in northern Chile contains a considerable number (7) of articulated partial skeletons tentatively assigned to Caraguatypotherium munozi (Notoungulata, Mesotheriidae), which presents up to 40% body size difference. Since either inter- and intra- specific wide size range has been observed in the Mesotheriidae family in general, we wanted explore the ontogenic stage signature of the sample, by carrying out the first comprehensive paleohistological description of the appendicular system in Notoungulata. Results show that: 1) they can be classified as subadults and adults, based on the presence of bone tissues typical of ceased somatic growth; 2) there is a notorious inter-skeletal variation on bone growth rates (skeletal modularity), particularly, the humerus showed a slower diameter growth and less remodelling than the femur, resulting as a better element for ontogenetic analyses; 3) marked cyclical growth is observed, characterised by fast early ontogenic continuous growth, and subsequent fast/slow stratified bone tissue layering. In general, such growth pattern suggests that C. munozi had a similar ontogenetic growth process as other modern mammals, that it should also be influenced by other sex-related, ecological and environmental factors. Likely related to the presence of rapid climatic variations, due to orogenic uplift and concomitant re-organization of the drainage processes along the western tectonic front of the Central Andes at that time.
Collapse
Affiliation(s)
- Jorge Campos-Medina
- Instituto de Ciencias de la Tierra, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Región de Los Ríos, Chile
- Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Coquimbo, Chile
- THERIUM SPA, Paleontología y Patrimonio, Curicó, Región del Maule
- * E-mail: (JCM); (KM); (GMS)
| | - Germán Montoya-Sanhueza
- Department of Zoology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
- * E-mail: (JCM); (KM); (GMS)
| | - Karen Moreno
- Instituto de Ciencias de la Tierra, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Región de Los Ríos, Chile
- * E-mail: (JCM); (KM); (GMS)
| | - Enrique Bostelmann Torrealba
- Instituto de Ciencias de la Tierra, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Región de Los Ríos, Chile
- Doctorado en Ciencias Mención Ecología y Evolución, Universidad Austral de Chile, Valdivia, Región de Los Ríos, Chile
- Museo Regional de Aysén, Coyhaique, Región de Aysén
| | - Marcelo García
- Departamento de Geología, Universidad de Chile, Santiago, Chile
| |
Collapse
|
5
|
Ercoli MD, Álvarez A, Youlatos D, Moyano SR, Candela AM. Tracing the Paleobiology of Paedotherium and Tremacyllus (Pachyrukhinae, Notoungulata), the Latest Sciuromorph South American Native Ungulates – Part II: Orbital, Auditory, and Occipito-Cervical Regions. J MAMM EVOL 2020. [DOI: 10.1007/s10914-020-09518-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
6
|
Tracing the Paleobiology of Paedotherium and Tremacyllus (Pachyrukhinae, Notoungulata), the Latest Sciuromorph South American Native Ungulates – Part I: Snout and Masticatory Apparatus. J MAMM EVOL 2020. [DOI: 10.1007/s10914-020-09516-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
7
|
Ercoli MD, Álvarez A, Candela AM. Sciuromorphy outside rodents reveals an ecomorphological convergence between squirrels and extinct South American ungulates. Commun Biol 2019; 2:202. [PMID: 31231692 PMCID: PMC6546766 DOI: 10.1038/s42003-019-0423-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 04/15/2019] [Indexed: 11/09/2022] Open
Abstract
Notoungulates were a diverse group of South American ungulates that included the rodent-like typotherians. However, they are typically compared with other ungulates and interpreted as grazers. Here we present the first detailed reconstruction of the masticatory muscles of the pachyrukhine typotherians Paedotherium and Tremacyllus. An outstanding feature is the presence of a true sciuromorph condition, defined by an anterior portion of the deep masseter muscle originating from a wide zygomatic plate that reaches the rostrum, a trait traceable since the Oligocene pachyrukhines. Consequently, pachyrukhines are the first case of sciuromorph non-rodent mammals. This morphology would have allowed them to explore ecological niches unavailable for the exclusively hystricomorph coexisting rodents. This innovative acquisition seems to be synchronous in Pachyrukhinae and sciuromorph rodents and related to hard-food consumption. We postulate the expansion of nut and cone trees during the major environmental changes at Eocene-Oligocene transition as a potential trigger for this convergence.
Collapse
Affiliation(s)
- Marcos D. Ercoli
- Instituto de Ecorregiones Andinas (INECOA), Universidad Nacional de Jujuy, CONICET, IdGyM, Av. Bolivia 1661, 4600 San Salvador de Jujuy, Jujuy Argentina
| | - Alicia Álvarez
- Instituto de Ecorregiones Andinas (INECOA), Universidad Nacional de Jujuy, CONICET, IdGyM, Av. Bolivia 1661, 4600 San Salvador de Jujuy, Jujuy Argentina
| | - Adriana M. Candela
- División de Paleontología de Vertebrados, Museo de La Plata, FCNyM, UNLP, CONICET, Paseo del Bosque s/n, 1900 La Plata, Buenos Aires Argentina
| |
Collapse
|