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Rossoni DM, Patterson BD, Marroig G, Cheverud JM, Houle D. The Role of (Co)variation in Shaping the Response to Selection in New World Leaf-Nosed Bats. Am Nat 2024; 203:E107-E127. [PMID: 38489775 DOI: 10.1086/729219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2024]
Abstract
AbstractUnderstanding and predicting the evolutionary responses of complex morphological traits to selection remains a major challenge in evolutionary biology. Because traits are genetically correlated, selection on a particular trait produces both direct effects on the distribution of that trait and indirect effects on other traits in the population. The correlations between traits can strongly impact evolutionary responses to selection and may thus impose constraints on adaptation. Here, we used museum specimens and comparative quantitative genetic approaches to investigate whether the covariation among cranial traits facilitated or constrained the response to selection during the major dietary transitions in one of the world's most ecologically diverse mammalian families-the phyllostomid bats. We reconstructed the set of net selection gradients that would have acted on each cranial trait during the major transitions to feeding specializations and decomposed the selection responses into their direct and indirect components. We found that for all transitions, most traits capturing craniofacial length evolved toward adaptive directions owing to direct selection. Additionally, we showed instances of dietary transitions in which the complex interaction between the patterns of covariation among traits and the strength and direction of selection either constrained or facilitated evolution. Our work highlights the importance of considering the within-species covariation estimates to quantify evolvability and to disentangle the relative contribution of variational constraints versus selective causes for observed patterns.
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2
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Machado FA, Mongle CS, Slater G, Penna A, Wisniewski A, Soffin A, Dutra V, Uyeda JC. Rules of teeth development align microevolution with macroevolution in extant and extinct primates. Nat Ecol Evol 2023; 7:1729-1739. [PMID: 37652997 DOI: 10.1038/s41559-023-02167-w] [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: 08/19/2022] [Accepted: 07/17/2023] [Indexed: 09/02/2023]
Abstract
Macroevolutionary biologists have classically rejected the notion that higher-level patterns of divergence arise through microevolutionary processes acting within populations. For morphology, this consensus partly derives from the inability of quantitative genetics models to correctly predict the behaviour of evolutionary processes at the scale of millions of years. Developmental studies (evo-devo) have been proposed to reconcile micro- and macroevolution. However, there has been little progress in establishing a formal framework to apply evo-devo models of phenotypic diversification. Here we reframe this issue by asking whether using evo-devo models to quantify biological variation can improve the explanatory power of comparative models, thus helping us bridge the gap between micro- and macroevolution. We test this prediction by evaluating the evolution of primate lower molars in a comprehensive dataset densely sampled across living and extinct taxa. Our results suggest that biologically informed morphospaces alongside quantitative genetics models allow a seamless transition between the micro- and macroscales, whereas biologically uninformed spaces do not. We show that the adaptive landscape for primate teeth is corridor like, with changes in morphology within the corridor being nearly neutral. Overall, our framework provides a basis for integrating evo-devo into the modern synthesis, allowing an operational way to evaluate the ultimate causes of macroevolution.
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Affiliation(s)
- Fabio A Machado
- Department of Integrative Biology, Oklahoma State University, Stillwater, OK, USA.
| | - Carrie S Mongle
- Department of Anthropology, Stony Brook University, Stony Brook, NY, USA
- Turkana Basin Institute, Stony Brook University, Stony Brook, NY, USA
| | - Graham Slater
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA
| | - Anna Penna
- Department of Anthropology, University of Texas at San Antonio, San Antonio, TX, USA
| | - Anna Wisniewski
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA
| | - Anna Soffin
- Department of Biology, Virginia Tech, Blacksburg, VA, USA
| | - Vitor Dutra
- Department of Anthropology, Florida Atlantic University, Boca Raton, FL, USA
| | - Josef C Uyeda
- Department of Biology, Virginia Tech, Blacksburg, VA, USA
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3
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Auerbach BM, Savell KRR, Agosto ER. Morphology, evolution, and the whole organism imperative: Why evolutionary questions need multi-trait evolutionary quantitative genetics. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2023. [PMID: 37060292 DOI: 10.1002/ajpa.24733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 04/16/2023]
Abstract
Since Washburn's New Physical Anthropology, researchers have sought to understand the complexities of morphological evolution among anatomical regions in human and non-human primates. Researchers continue, however, to preferentially use comparative and functional approaches to examine complex traits, but these methods cannot address questions about evolutionary process and often conflate function with fitness. Moreover, researchers also tend to examine anatomical elements in isolation, which implicitly assumes independent evolution among different body regions. In this paper, we argue that questions asked in primate evolution are best examined using multiple anatomical regions subjected to model-bound methods built from an understanding of evolutionary quantitative genetics. A nascent but expanding number of studies over the last two decades use this approach, examining morphological integration, evolvability, and selection modeling. To help readers learn how to use these methods, we review fundamentals of evolutionary processes within a quantitative genetic framework, explore the importance of neutral evolutionary theory, and explain the basics of evolutionary quantitative genetics, namely the calculation of evolutionary potential for multiple traits in response to selection. Leveraging these methods, we demonstrate their use to understand non-independence in possible evolutionary responses across the limbs, limb girdles, and basicranium of humans. Our results show that model-bound quantitative genetic methods can reveal unexpected genetic covariances among traits that create a novel but measurable understanding of evolutionary complexity among multiple traits. We advocate for evolutionary quantitative genetic methods to be a standard whenever appropriate to keep studies of primate morphological evolution relevant for the next seventy years and beyond.
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Affiliation(s)
- Benjamin M Auerbach
- Department of Anthropology, The University of Tennessee, Knoxville, Tennessee, USA
- Department of Ecology and Evolutionary Biology, The University of Tennessee, Knoxville, Tennessee, USA
| | - Kristen R R Savell
- Department of Biology, Sacred Heart University, Fairfield, Connecticut, USA
| | - Elizabeth R Agosto
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
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4
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Diversification of the shell shape and size in Baikal Candonidae ostracods inferred from molecular phylogeny. Sci Rep 2023; 13:2950. [PMID: 36806355 PMCID: PMC9941104 DOI: 10.1038/s41598-023-30003-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
Ostracod shells are used extensively in paleontology, but we know little about their evolution, especially in ancient lakes. Lake Baikal (LB) is the world's most important stronghold of Candonidae diversity. These crustaceans radiated here rapidly (12-5 Ma) and with an unprecedented morphological diversity. We reconstruct their molecular phylogeny with 46 species and two markers (18S and 16S rRNA), and use it to estimate the evolution of the shell shape and size with landmark-based geometric morphometrics (LBGM). High posterior probabilities support four major clades, which differ in node depth and morphospace clustering. After removing a significant allometry, the first three principal components (PCs) describe about 88% of total variability, suggesting a strong integration. Reconstructed ancestral shapes are similar for all four clades, indicating that diversification happened after colonization. Major evolutionary changes occurred from trapezoidal to elongated shapes. Sister species are separated in morphospace, by centroid size, or both, as well as by vertical and horizontal distributions in LB. Ostracod shell is a strongly integrated structure that exhibits high evolvability, with some extreme shapes, although mostly along the first PC. This is the first study that combines molecular phylogeny and LBGM for ostracods and for any LB group.
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5
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Rothier PS, Fabre AC, Clavel J, Benson RBJ, Herrel A. Mammalian forelimb evolution is driven by uneven proximal-to-distal morphological diversity. eLife 2023; 12:81492. [PMID: 36700542 PMCID: PMC9908075 DOI: 10.7554/elife.81492] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 01/24/2023] [Indexed: 01/27/2023] Open
Abstract
Vertebrate limb morphology often reflects the environment due to variation in locomotor requirements. However, proximal and distal limb segments may evolve differently from one another, reflecting an anatomical gradient of functional specialization that has been suggested to be impacted by the timing of development. Here, we explore whether the temporal sequence of bone condensation predicts variation in the capacity of evolution to generate morphological diversity in proximal and distal forelimb segments across more than 600 species of mammals. Distal elements not only exhibit greater shape diversity, but also show stronger within-element integration and, on average, faster evolutionary responses than intermediate and upper limb segments. Results are consistent with the hypothesis that late developing distal bones display greater morphological variation than more proximal limb elements. However, the higher integration observed within the autopod deviates from such developmental predictions, suggesting that functional specialization plays an important role in driving within-element covariation. Proximal and distal limb segments also show different macroevolutionary patterns, albeit not showing a perfect proximo-distal gradient. The high disparity of the mammalian autopod, reported here, is consistent with the higher potential of development to generate variation in more distal limb structures, as well as functional specialization of the distal elements.
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Affiliation(s)
- Priscila S Rothier
- Département Adaptations du Vivant, Muséum National d'Histoire NaturelleParisFrance
| | - Anne-Claire Fabre
- Naturhistorisches Museum BernBernSwitzerland
- Institute of Ecology and Evolution, University of BernBernSwitzerland
- Life Sciences Department, Vertebrates Division, Natural History MuseumLondonUnited Kingdom
| | - Julien Clavel
- Life Sciences Department, Vertebrates Division, Natural History MuseumLondonUnited Kingdom
- Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR 5023VilleurbanneFrance
| | - Roger BJ Benson
- Department of Earth Sciences, University of OxfordOxfordUnited Kingdom
| | - Anthony Herrel
- Département Adaptations du Vivant, Muséum National d'Histoire NaturelleParisFrance
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6
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Homo sapiens and Neanderthals share high cerebral cortex integration into adulthood. Nat Ecol Evol 2023; 7:42-50. [PMID: 36604552 DOI: 10.1038/s41559-022-01933-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 10/11/2022] [Indexed: 01/07/2023]
Abstract
There is controversy around the mechanisms that guided the change in brain shape during the evolution of modern humans. It has long been held that different cortical areas evolved independently from each other to develop their unique functional specializations. However, some recent studies suggest that high integration between different cortical areas could facilitate the emergence of equally extreme, highly specialized brain functions. Here, we analyse the evolution of brain shape in primates using three-dimensional geometric morphometrics of endocasts. We aim to determine, firstly, whether modern humans present unique developmental patterns of covariation between brain cortical areas; and secondly, whether hominins experienced unusually high rates of evolution in brain covariation as compared to other primates. On the basis of analyses including modern humans and other extant great apes at different developmental stages, we first demonstrate that, unlike our closest living relatives, Homo sapiens retain high levels of covariation between cortical areas into adulthood. Among the other great apes, high levels of covariation are only found in immature individuals. Secondly, at the macro-evolutionary level, our analysis of 400 endocasts, representing 148 extant primate species and 6 fossil hominins, shows that strong covariation between different areas of the brain in H. sapiens and Homo neanderthalensis evolved under distinctly higher evolutionary rates than in any other primate, suggesting that natural selection favoured a greatly integrated brain in both species. These results hold when extinct species are excluded and allometric effects are accounted for. Our findings demonstrate that high covariation in the brain may have played a critical role in the evolution of unique cognitive capacities and complex behaviours in both modern humans and Neanderthals.
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7
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Conaway MA, Adams DC. An effect size for comparing the strength of morphological integration across studies. Evolution 2022; 76:2244-2259. [PMID: 35971251 DOI: 10.1111/evo.14595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 06/16/2022] [Indexed: 01/22/2023]
Abstract
Understanding how and why phenotypic traits covary is a major interest in evolutionary biology. Biologists have long sought to characterize the extent of morphological integration in organisms, but comparing levels of integration for a set of traits across taxa has been hampered by the lack of a reliable summary measure and testing procedure. Here, we propose a standardized effect size for this purpose, calculated from the relative eigenvalue variance, V r e l $V_{rel}$ . First, we evaluate several eigenvalue dispersion indices under various conditions, and show that only V r e l $V_{rel}$ remains stable across samples size and the number of variables. We then demonstrate that V r e l $V_{rel}$ accurately characterizes input patterns of covariation, so long as redundant dimensions are excluded from the calculations. However, we also show that the variance of the sampling distribution of V r e l $V_{rel}$ depends on input levels of trait covariation, making V r e l $V_{rel}$ unsuitable for direct comparisons. As a solution, we propose transforming V r e l $V_{rel}$ to a standardized effect size (Z-score) for representing the magnitude of integration for a set of traits. We also propose a two-sample test for comparing the strength of integration between taxa, and show that this test displays appropriate statistical properties. We provide software for implementing the procedure, and an empirical example illustrates its use.
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Affiliation(s)
- Mark A Conaway
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, Iowa, USA
| | - Dean C Adams
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, Iowa, USA
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8
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La Fortezza M, Rendueles O, Keller H, Velicer GJ. Hidden paths to endless forms most wonderful: ecology latently shapes evolution of multicellular development in predatory bacteria. Commun Biol 2022; 5:977. [PMID: 36114258 PMCID: PMC9481553 DOI: 10.1038/s42003-022-03912-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 08/30/2022] [Indexed: 11/09/2022] Open
Abstract
AbstractEcological causes of developmental evolution, for example from predation, remain much investigated, but the potential importance of latent phenotypes in eco-evo-devo has received little attention. Using the predatory bacterium Myxococcus xanthus, which undergoes aggregative fruiting body development upon starvation, we tested whether adaptation to distinct growth environments that do not induce development latently alters developmental phenotypes under starvation conditions that do induce development. In an evolution experiment named MyxoEE-3, growing M. xanthus populations swarmed across agar surfaces while adapting to conditions varying at factors such as surface stiffness or prey identity. Such ecological variation during growth was found to greatly impact the latent evolution of development, including fruiting body morphology, the degree of morphological trait correlation, reaction norms, degrees of developmental plasticity and stochastic diversification. For example, some prey environments promoted retention of developmental proficiency whereas others led to its systematic loss. Our results have implications for understanding evolutionary interactions among predation, development and motility in myxobacterial life cycles, and, more broadly, how ecology can profoundly shape the evolution of developmental systems latently rather than by direct selection on developmental features.
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9
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Sanaphre-Villanueva L, Pineda-García F, Dáttilo W, Pinzón-Pérez LF, Ricaño-Rocha A, Paz H. Above- and below-ground trait coordination in tree seedlings depend on the most limiting resource: a test comparing a wet and a dry tropical forest in Mexico. PeerJ 2022; 10:e13458. [PMID: 35722267 PMCID: PMC9205306 DOI: 10.7717/peerj.13458] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 04/27/2022] [Indexed: 01/14/2023] Open
Abstract
The study of above- and below-ground organ plant coordination is crucial for understanding the biophysical constraints and trade-offs involved in species' performance under different environmental conditions. Environmental stress is expected to increase constraints on species trait combinations, resulting in stronger coordination among the organs involved in the acquisition and processing of the most limiting resource. To test this hypothesis, we compared the coordination of trait combinations in 94 tree seedling species from two tropical forest systems in Mexico: dry and moist. In general, we expected that the water limitation experienced by dry forest species would result in stronger leaf-stem-root coordination than light limitation experienced by moist forest species. Using multiple correlations analyses and tools derived from network theory, we found similar functional trait coordination between forests. However, the most important traits differed between the forest types. While in the dry forest the most central traits were all related to water storage (leaf and stem water content and root thickness), in the moist forest they were related to the capacity to store water in leaves (leaf water content), root efficiency to capture resources (specific root length), and stem toughness (wood density). Our findings indicate that there is a shift in the relative importance of mechanisms to face the most limiting resource in contrasting tropical forests.
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Affiliation(s)
- Lucía Sanaphre-Villanueva
- Centro del Cambio Global y la Sustentabilidad A.C., Consejo Nacional de Ciencia y Tecnología, Villahermosa, Tabasco, México,Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, México
| | - Fernando Pineda-García
- Escuela Nacional de Estudios Superiores, Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Michoacán, México
| | - Wesley Dáttilo
- Red de Ecoetología, Instituto de Ecología, A.C., Xalapa, Veracruz, México
| | - Luisa Fernanda Pinzón-Pérez
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, México
| | - Arlett Ricaño-Rocha
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, México
| | - Horacio Paz
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, México,Laboratorio Nacional de Innovación Ecotecnológica para la Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, México,Center for Stable Isotope Biogeochemistry and the Department of Integrative Biology, University of California, Berkeley, CA, United States of America
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10
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Edie SM, Khouja SC, Collins KS, Crouch NMA, Jablonski D. Evolutionary modularity, integration and disparity in an accretionary skeleton: analysis of venerid Bivalvia. Proc Biol Sci 2022; 289:20211199. [PMID: 35042422 PMCID: PMC8767195 DOI: 10.1098/rspb.2021.1199] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Modular evolution, the relatively independent evolution of body parts, may promote high morphological disparity in a clade. Conversely, integrated evolution via stronger covariation of parts may limit disparity. However, integration can also promote high disparity by channelling morphological evolution along lines of least resistance-a process that may be particularly important in the accumulation of disparity in the many invertebrate systems having accretionary growth. We use a time-calibrated phylogenetic hypothesis and high-density, three-dimensional semilandmarking to analyse the relationship between modularity, integration and disparity in the most diverse extant bivalve family: the Veneridae. In general, venerids have a simple, two-module parcellation of their body that is divided into features of the calcium carbonate shell and features of the internal soft anatomy. This division falls more along developmental than functional lines when placed in the context of bivalve anatomy and biomechanics. The venerid body is tightly integrated in absolute terms, but disparity appears to increase with modularity strength among subclades and ecologies. Thus, shifts towards more mosaic evolution beget higher morphological variance in this speciose family.
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Affiliation(s)
- Stewart M. Edie
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA
| | - Safia C. Khouja
- Department of the Geophysical Sciences, University of Chicago, 5734 South Ellis Ave, Chicago, IL 60637, USA
| | - Katie S. Collins
- Department of Earth Sciences, Invertebrates and Plants Palaeobiology Division, Natural History Museum, London SW7 5BD, UK
| | - Nicholas M. A. Crouch
- Department of the Geophysical Sciences, University of Chicago, 5734 South Ellis Ave, Chicago, IL 60637, USA
| | - David Jablonski
- Department of the Geophysical Sciences, University of Chicago, 5734 South Ellis Ave, Chicago, IL 60637, USA,Committee on Evolutionary Biology, University of Chicago, Chicago, IL 60637, USA
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11
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Machado FA, Marroig G, Hubbe A. The pre-eminent role of directional selection in generating extreme morphological change in glyptodonts (Cingulata; Xenarthra). Proc Biol Sci 2022; 289:20212521. [PMID: 35042420 PMCID: PMC8767197 DOI: 10.1098/rspb.2021.2521] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 12/14/2021] [Indexed: 01/28/2023] Open
Abstract
The prevalence of stasis on macroevolution has been classically taken as evidence of the strong role of stabilizing selection in constraining morphological change. Rates of evolution calculated over longer timescales tend to fall below the expected under genetic drift, suggesting that directional selection signals are erased at longer timescales. Here, we investigated the rates of morphological evolution of the skull in a fossil lineage that underwent extreme morphological modification, the glyptodonts. Contrary to what was expected, we show here that directional selection was the primary process during the evolution of glyptodonts. Furthermore, the reconstruction of selection patterns shows that traits selected to generate a glyptodont morphology are markedly different from those operating on extant armadillos. Changes in both direction and magnitude of selection are probably tied to glyptodonts' invasion of a specialist-herbivore adaptive zone. These results suggest that directional selection might have played a more critical role in the evolution of extreme morphologies than previously imagined.
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Affiliation(s)
| | - Gabriel Marroig
- Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Alex Hubbe
- Departamento de Oceanografia, Instituto de Geociências, Universidade Federal da Bahia, Salvador, Brazil
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12
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Watanabe J. Statistics of eigenvalue dispersion indices: Quantifying the magnitude of phenotypic integration. Evolution 2021; 76:4-28. [PMID: 34679186 DOI: 10.1111/evo.14382] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/13/2021] [Accepted: 09/20/2021] [Indexed: 01/28/2023]
Abstract
Analysis of trait covariation plays a pivotal role in the study of phenotypic evolution. The magnitude of covariation is often quantified with statistics based on dispersion of eigenvalues of a covariance or correlation matrix-eigenvalue dispersion indices. This study clarifies the statistical justifications of these statistics and elaborates on their sampling properties. The relative eigenvalue variance of a covariance matrix is known in the statistical literature a test statistic for sphericity, and thus is an appropriate measure of eccentricity of variation. The same of a correlation matrix is equal to the average squared correlation, which has a straightforward interpretation as a measure of integration. Here, expressions for the mean and variance of these statistics are analytically derived under multivariate normality, clarifying the effects of sample size N, number of variables p, and parameters on sampling bias and error. Simulations confirm that approximations involved are reasonably accurate with a moderate sample size (N ≥ 16-64). Importantly, sampling properties of these indices are not adversely affected by a high p:N ratio, promising their utility in high-dimensional phenotypic analyses. They can furthermore be applied to shape variables and phylogenetically structured data with appropriate modifications.
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Affiliation(s)
- Junya Watanabe
- Department of Earth Sciences, University of Cambridge, Cambridge, United Kingdom
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13
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Meloro C, Tamagnini D. Macroevolutionary ecomorphology of the Carnivora skull: adaptations and constraints in the extant species. Zool J Linn Soc 2021. [DOI: 10.1093/zoolinnean/zlab075] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
The mammalian order Carnivora is characterized by a broad taxonomic and ecological diversity. By using a large sample of extant species, we tested the impact of ecological factors on carnivoran skull (cranium and mandible) morphology, taking advantage of a combined geometric morphometrics and comparative method approach. We implemented several evolutionary models to account for different tempo and mode of evolution in size and shape data. These models validated the association between skull morphology and diet at the interspecific scale. The functional distinction between pinniped (aquatic) and fissiped (mostly terrestrial) taxa was found valid only in mandible shape and cranial size. High levels of morphological disparity and evolutionary rates were identified in specialized dietary groups, and positive association between rates and disparity was found for skull size. Cranium and mandible showed consistent patterns of covariation that reflect constrained functional processes, which stabilize the ecomorphological evolution of Carnivora. Aquatic adaptations allowed carnivorans to invade and persist within novel regions of the mandibular morphospace. This ecological shift did not increase morphological disparity but occurred at a faster rate than in terrestrial species. Those species exhibit a stronger level of cranio-mandibular covariation due to constraints imposed by more demanding masticatory adaptations.
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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
| | - Davide Tamagnini
- Department of Biology and Biotechnologies ‘Charles Darwin’, University of Rome La Sapienza, Rome, Italy
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14
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Hanot P, Bayarsaikhan J, Guintard C, Haruda A, Mijiddorj E, Schafberg R, Taylor W. Cranial shape diversification in horses: variation and covariation patterns under the impact of artificial selection. BMC Ecol Evol 2021; 21:178. [PMID: 34548035 PMCID: PMC8456661 DOI: 10.1186/s12862-021-01907-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/06/2021] [Indexed: 01/04/2023] Open
Abstract
The potential of artificial selection to dramatically impact phenotypic diversity is well known. Large-scale morphological changes in domestic species, emerging over short timescales, offer an accelerated perspective on evolutionary processes. The domestic horse (Equus caballus) provides a striking example of rapid evolution, with major changes in morphology and size likely stemming from artificial selection. However, the microevolutionary mechanisms allowing to generate this variation in a short time interval remain little known. Here, we use 3D geometric morphometrics to quantify skull morphological diversity in the horse, and investigate modularity and integration patterns to understand how morphological associations contribute to cranial evolvability in this taxon. We find that changes in the magnitude of cranial integration contribute to the diversification of the skull morphology in horse breeds. Our results demonstrate that a conserved pattern of modularity does not constrain large-scale morphological variations in horses and that artificial selection has impacted mechanisms underlying phenotypic diversity to facilitate rapid shape changes. More broadly, this study demonstrates that studying microevolutionary processes in domestic species produces important insights into extant phenotypic diversity.
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Affiliation(s)
- Pauline Hanot
- Department of Archaeology, Max Planck Institute for the Science of Human History, Kahlaische Straße 10, 07745, Jena, Germany.
| | - Jamsranjav Bayarsaikhan
- Department of Archaeology, Max Planck Institute for the Science of Human History, Kahlaische Straße 10, 07745, Jena, Germany.,National Museum of Mongolia, 1 Juulchin Street, Ulaanbaatar, 15160, Mongolia
| | - Claude Guintard
- Unité d'Anatomie Comparée, Ecole Nationale Vétérinaire de l'Agroalimentaire et de l'Alimentation, Nantes Atlantique - ONIRIS, Route de Gachet, CS 40706, 44307, Nantes Cedex 03, France.,Groupe d'Etudes Remodelage osseux et bioMateriaux (GEROM), Unité INSERM 922 LHEA/IRIS-IBS, Université d'Angers, 4 rue Larrey CHU d'Angers, Angers, France
| | - Ashleigh Haruda
- Central Natural Science Collections (ZNS), Martin-Luther University Halle-Wittenberg, Domplatz 4, 06108, Halle (Saale), Germany.,School of Archaeology, University of Oxford, 1-2 South Parks Road, Oxford, OX1 3TG, UK
| | - Enkhbayar Mijiddorj
- Department of Archaeology, Ulaanbaatar State University, Luvsantseveen Street, 5th Khoroo, 15th Khoroolol, Bayanzurkh District, Ulaanbaatar, 13343, Mongolia
| | - Renate Schafberg
- Central Natural Science Collections (ZNS), Martin-Luther University Halle-Wittenberg, Domplatz 4, 06108, Halle (Saale), Germany
| | - William Taylor
- University of Colorado-Boulder, Museum of Natural History, Boulder, CO, USA
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Rhoda D, Segall M, Larouche O, Evans K, Angielczyk KD. Local superimpositions facilitate morphometric analysis of complex articulating structures. Integr Comp Biol 2021; 61:1892-1904. [PMID: 33905523 PMCID: PMC8699094 DOI: 10.1093/icb/icab031] [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] [Indexed: 11/16/2022] Open
Abstract
Articulating structures, such as the vertebrate skeleton or the segmented arthropod exoskeleton, comprise a majority of the morphological diversity across the eukaryotic tree of life. Quantifying the form of articulating structures is therefore imperative for a fuller understanding of the factors influencing biological form. A wealth of freely available 3D data capturing this morphological diversity is stored in online repositories such as Morphosource, but the geometric morphometric analysis of an articulating structure is impeded by arbitrary differences in the resting positions of its individual articulating elements. In complex articulating structures, where the angles between articulating elements cannot be standardized, landmarks on articulating elements must be Procrustes superimposed independently (locally) and then recombined to quantify variation in the entire articulating structure simultaneously. Here, we discuss recent advances in local superimposition techniques, namely the “matched local superimpositions” approach, which incorporates anatomically accurate relative sizes, positions, and orientations of locally-superimposed landmarks, enabling clearer biological interpretation. We also use simulations to evaluate the consequences of choice of superimposition approach. Our results show that local superimpositions will isolate shape variation within locally-superimposed landmark subsets by sacrificing size and positional variation. They may also create morphometric “modules” when there are none by increasing integration within the locally-superimposed subsets; however, this effect is no greater than the spurious between-module integration created when superimposing landmark subsets (i.e., articulating elements) together. Taken together, our results show that local superimposition techniques differ from conventional Procrustes superimpositions in predictable ways. Finally, we use empirical datasets of the skulls of wrasses and colubriform snakes to highlight the promise of local superimpositions and their utility. Complex articulating structures must be studied, and the only current solution to do so is local superimpositions.
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Affiliation(s)
- Daniel Rhoda
- Committee on Evolutionary Biology, University of Chicago, 5801 S Ellis Ave, Chicago, IL 60637, USA
| | - Marion Segall
- Department of Herpetology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA
| | - Olivier Larouche
- Department of BioSciences, Rice University, 6100 Main St, Houston, TX 77005, USA
| | - Kory Evans
- Department of BioSciences, Rice University, 6100 Main St, Houston, TX 77005, USA
| | - Kenneth D Angielczyk
- Negaunee Integrative Research Center, Field Museum of Natural History, 1400 South Lake Shore Drive, Chicago, Illinois 60605, USA
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Michaud M, Veron G, Fabre AC. Phenotypic integration in feliform carnivores: Covariation patterns and disparity in hypercarnivores versus generalists. Evolution 2020; 74:2681-2702. [PMID: 33085081 DOI: 10.1111/evo.14112] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 08/01/2020] [Accepted: 10/03/2020] [Indexed: 01/01/2023]
Abstract
The skeleton is a complex arrangement of anatomical structures that covary to various degrees depending on both intrinsic and extrinsic factors. Among the Feliformia, many species are characterized by predator lifestyles providing a unique opportunity to investigate the impact of highly specialized hypercarnivorous diet on phenotypic integration and shape diversity. To do so, we compared the shape of the skull, mandible, humerus, and femur of species in relation to their feeding strategies (hypercarnivorous vs. generalist species) and prey preference (predators of small vs. large prey) using three-dimensional geometric morphometric techniques. Our results highlight different degrees of morphological integration in the Feliformia depending on the functional implication of the anatomical structure, with an overall higher covariation of structures in hypercarnivorous species. The skull and the forelimb are not integrated in generalist species, whereas they are integrated in hypercarnivores. These results can potentially be explained by the different feeding strategies of these species. Contrary to our expectations, hypercarnivores display a higher disparity for the skull than generalist species. This is probably due to the fact that a specialization toward high-meat diet could be achieved through various phenotypes. Finally, humeri and femora display shape variations depending on relative prey size preference. Large species feeding on large prey tend to have robust long bones due to higher biomechanical constraints.
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Affiliation(s)
- Margot Michaud
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, Paris, 75231 cedex 05, France
| | - Géraldine Veron
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, Paris, 75231 cedex 05, France
| | - Anne-Claire Fabre
- Department of Life Sciences, The Natural History Museum, London, SW7 5BD, United Kingdom
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Machado FA. Selection and Constraints in the Ecomorphological Adaptive Evolution of the Skull of Living Canidae (Carnivora, Mammalia). Am Nat 2020; 196:197-215. [PMID: 32673094 DOI: 10.1086/709610] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The association between phenotype and ecology is essential for understanding the environmental drivers of morphological evolution. This is a particularly challenging task when dealing with complex traits, such as the skull, where multiple selective pressures are at play and evolution might be constrained by ontogenetic and genetic factors. I integrate morphometric tools, comparative methods, and quantitative genetics to investigate how ontogenetic constraints and selection might have interacted during the evolution of the skull in extant Canidae. The results confirm that the evolution of cranial morphology was largely adaptive and molded by changes in diet composition. While the investigation of the adaptive landscape reveals two main selective lines of least resistance (one associated with size and one associated with functional shape features), rates of evolution along size were higher than those found for shape dimensions, suggesting the influence of constraints on morphological evolution. Structural modeling analyses revealed that size, which is the line of most genetic/phenotypic variation, might have acted as a constraint, negatively impacting dietary evolution. Constraints might have been overcome in the case of selection for the consumption of large prey by associating strong selection along both size and shape directions. The results obtained here show that microevolutionary constraints may have played a role in shaping macroevolutionary patterns of morphological evolution.
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The Skull Integration Pattern and Internal Constraints in Myotis myotis–Myotis blythii Species Group (Vespertilionidae, Chiroptera) Might be Shaped by Natural Selection During Evolution Along the Genetic Line of Least Resistance. Evol Biol 2019. [DOI: 10.1007/s11692-019-09488-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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