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Balaguera-Reina SA, Mason BM, Brandt LA, Hernandez ND, Daykin BL, McCaffrey KR, Godfrey ST, Mazzotti FJ. Ecological implications of allometric relationships in American alligators (Alligator mississippiensis). Sci Rep 2024; 14:6140. [PMID: 38480785 PMCID: PMC10937943 DOI: 10.1038/s41598-024-56798-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 03/11/2024] [Indexed: 03/17/2024] Open
Abstract
Morphometric allometry, the effect of size on morphological variation, has been of great interest for evolutionary biologist and is currently used in fields such as wildlife ecology to inform management and conservation. We assessed American alligator (Alligator mississippiensis) morphological static allometry across the Greater Everglades ecosystem in South Florida, United States using a robust dataset (~ 22 years) and investigated effects of sex, habitat, and sampling area on morphological relationships. Regression models showed very strong evidence of a linear relationship between variables explaining equal to or above 92% of the variation in the data. Most trait-size relationships (8 out of 11 assessed) showed hyperallometry (positive allometry) with slope deviations from isometry between 0.1 and 0.2 units while the other three relationships were isometric. Sampling area, type of habitat, and in a lesser extent sex influenced allometric coefficients (slope and intercept) across several relationships, likely as result of differing landscapes and ecosystem dynamic alterations and sexual dimorphism. We discuss our findings in terms of the biology of the species as well as the usefulness of our results in the context of ecosystem restoration and conservation of the species. Finally, we provide recommendations when using trait-length relationships to infer population nutritional-health condition and demographics.
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Affiliation(s)
- Sergio A Balaguera-Reina
- Department of Wildlife Ecology and Conservation, Fort Lauderdale Research and Education Center, University of Florida, Fort Lauderdale, 33328, USA.
| | - Brittany M Mason
- Department of Wildlife Ecology and Conservation, Fort Lauderdale Research and Education Center, University of Florida, Fort Lauderdale, 33328, USA
| | - Laura A Brandt
- U.S. Fish and Wildlife Service, Fort Lauderdale, 33328, USA
| | - Nicole D Hernandez
- Department of Wildlife Ecology and Conservation, Fort Lauderdale Research and Education Center, University of Florida, Fort Lauderdale, 33328, USA
| | - Bryna L Daykin
- Department of Wildlife Ecology and Conservation, Fort Lauderdale Research and Education Center, University of Florida, Fort Lauderdale, 33328, USA
| | - Kelly R McCaffrey
- Department of Wildlife Ecology and Conservation, Fort Lauderdale Research and Education Center, University of Florida, Fort Lauderdale, 33328, USA
| | - Sidney T Godfrey
- Department of Wildlife Ecology and Conservation, Fort Lauderdale Research and Education Center, University of Florida, Fort Lauderdale, 33328, USA
| | - Frank J Mazzotti
- Department of Wildlife Ecology and Conservation, Fort Lauderdale Research and Education Center, University of Florida, Fort Lauderdale, 33328, USA
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Wilcox AS, Vea IM, Frankino WA, Shingleton AW. Genetic variation of morphological scaling in Drosophila melanogaster. Heredity (Edinb) 2023; 130:302-311. [PMID: 36878946 PMCID: PMC10162999 DOI: 10.1038/s41437-023-00603-y] [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: 06/07/2022] [Revised: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 03/08/2023] Open
Abstract
Morphological scaling relationships between the sizes of individual traits and the body captures the characteristic shape of a species, and their evolution is the primary mechanism of morphological diversification. However, we have almost no knowledge of the genetic variation of scaling, which is critical if we are to understand how scaling evolves. Here we explore the genetics of population scaling relationships (scaling relationships fit to multiple genetically-distinct individuals in a population) by describing the distribution of individual scaling relationships (genotype-specific scaling relationships that are unseen or cryptic). These individual scaling relationships harbor the genetic variation in the developmental mechanisms that regulate trait growth relative to body growth, and theoretical studies suggest that their distribution dictates how the population scaling relationship will respond to selection. Using variation in nutrition to generate size variation within 197 isogenic lineages of Drosophila melanogaster, we reveal extensive variation in the slopes of the wing-body and leg-body individual scaling relationships among genotypes. This variation reflects variation in the nutritionally-induced size plasticity of the wing, leg, and body. Surprisingly, we find that variation in the slope of individual scaling relationships primarily results from variation in nutritionally-induced plasticity of body size, not leg or wing size. These data allow us to predict how different selection regimes affect scaling in Drosophila, and is the first step in identifying the genetic targets of such selection. More generally, our approach provides a framework for understanding the genetic variation of scaling, an important prerequisite to explaining how selection changes scaling and morphology.
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Affiliation(s)
- Austin S Wilcox
- Department of Biological Sciences, University of Illinois Chicago, 840 W Taylor St, Chicago, IL, 60607, USA
| | - Isabelle M Vea
- Department of Biological Sciences, University of Illinois Chicago, 840 W Taylor St, Chicago, IL, 60607, USA
| | - W Anthony Frankino
- Department of Biology and Biochemistry, University of Houston, Houston, TX, 77204, USA
| | - Alexander W Shingleton
- Department of Biological Sciences, University of Illinois Chicago, 840 W Taylor St, Chicago, IL, 60607, USA.
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Summers TC, Ord TJ. Signal detection shapes ornament allometry in functionally convergent Caribbean Anolis and Southeast Asian Draco lizards. J Evol Biol 2022; 35:1508-1523. [PMID: 36177770 PMCID: PMC9828585 DOI: 10.1111/jeb.14102] [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: 08/20/2021] [Revised: 07/10/2022] [Accepted: 07/21/2022] [Indexed: 01/12/2023]
Abstract
Visual ornaments have long been assumed to evolve hyper-allometry as an outcome of sexual selection. Yet growing evidence suggests many sexually selected morphologies can exhibit other scaling patterns with body size, including hypo-allometry. The large conspicuous throat fan, or dewlap, of arboreal Caribbean Anolis lizards was one ornament previously thought to conform to the classical expectation of hyper-allometry. We re-evaluated this classic example alongside a second arboreal group of lizards that has also independently evolved a functionally equivalent dewlap, the Southeast Asian Draco lizards. Across multiple closely related species in both genera, the Anolis and Draco dewlaps were either isometric or had hypo-allometric scaling patterns. In the case of the Anolis dewlap, variation in dewlap allometry was predicted by the distance of conspecifics and the light environment in which the dewlap was typically viewed. Signal efficacy, therefore, appears to have driven the evolution of hypo-allometry in what was originally thought to be a sexually selected ornament with hyper-allometry. Our findings suggest that other elaborate morphological structures used in social communication might similarly exhibit isometric or hypo-allometric scaling patterns because of environmental constraints on signal detection.
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Affiliation(s)
- Thomas C. Summers
- Evolution and Ecology Research Centre, and the School of Biological, Earth and Environmental SciencesUniversity of New South WalesKensingtonNew South WalesAustralia
| | - Terry J. Ord
- Evolution and Ecology Research Centre, and the School of Biological, Earth and Environmental SciencesUniversity of New South WalesKensingtonNew South WalesAustralia
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4
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Female preference for super-sized male ornaments and its implications for the evolution of ornament allometry. Evol Ecol 2022. [DOI: 10.1007/s10682-022-10181-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractIt has been argued that disproportionately larger ornaments in bigger males—positive allometry—is the outcome of sexual selection operating on the size of condition dependent traits. We reviewed the literature and found a general lack of empirical testing of the assumed link between female preferences for large ornaments and a pattern of positive allometry in male ornamentation. We subsequently conducted a manipulative experiment by leveraging the unusual terrestrial fish, Alticus sp. cf. simplicirrus, on the island of Rarotonga. Males in this species present a prominent head crest to females during courtship, and the size of this head crest in the genus more broadly exhibits the classic pattern of positive allometry. We created realistic male models standardized in body size but differing in head crest size based on the most extreme allometric scaling recorded for the genus. This included a crest size well outside the observed range for the study population (super-sized). The stimuli were presented to free-living females in a manner that mimicked the spatial distribution of courting males. Females directed greater attention to the male stimulus that exhibited the super-sized crest, with little difference in attention direct to other size treatments. These data appear to be the only experimental evidence from the wild of a female preference function that has been implicitly assumed to drive selection that results in the evolution of positive allometry in male ornamentation.
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Summers TC, Ord TJ. The stabilising impact of natural selection on the allometry of sexual ornaments: Fish that escape locomotor constraints exhibit extravagant ornamentation. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13968] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Thomas C. Summers
- Evolution and Ecology Research Centre, and the School of Biological, Earth and Environmental Sciences University of New South Wales Kensington NSW Australia
| | - Terry J. Ord
- Evolution and Ecology Research Centre, and the School of Biological, Earth and Environmental Sciences University of New South Wales Kensington NSW Australia
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Pélabon C, Côté SD, Festa‐Bianchet M, Gaillard J, Garel M, Lemaître J, Loison A, Tidière M, Toïgo C. Effects of population density on static allometry between horn length and body mass in mountain ungulates. OIKOS 2021. [DOI: 10.1111/oik.08726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christophe Pélabon
- Dept of Biology, Centre for Biodiversity Dynamics, Norwegian Univ. of Science and Technology Trondheim Norway
| | - Steeve D. Côté
- Dépt de Biologie and Centre d'Etudes Nordiques, Univ. Laval Québec QC Canada
| | | | - Jean‐Michel Gaillard
- Laboratoire de Biométrie et Biologie Evolutive, UMR5558, Univ. de Lyon, Université Lyon 1, CNRS Villeurbanne France
| | - Mathieu Garel
- Office Français de la Biodiversité, Unité Ongulés Sauvages, ZI Mayencin Gières France
| | - Jean‐Francois Lemaître
- Laboratoire de Biométrie et Biologie Evolutive, UMR5558, Univ. de Lyon, Université Lyon 1, CNRS Villeurbanne France
| | - Anne Loison
- Univ. Grenoble Alpes, Univ. Savoie Mont‐Blanc, CNRS, LECA Grenoble France
| | - Morgane Tidière
- Species360 Conservation Science Alliance Bloomington Minnesota USA
- Interdisciplinary Centre on Population Dynamics, Dept of Biology, Univ. of Southern Denmark Odense M Denmark
| | - Carole Toïgo
- Office Français de la Biodiversité, Unité Ongulés Sauvages, ZI Mayencin Gières France
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Unger CM, Devine J, Hallgrímsson B, Rolian C. Selection for increased tibia length in mice alters skull shape through parallel changes in developmental mechanisms. eLife 2021; 10:67612. [PMID: 33899741 PMCID: PMC8118654 DOI: 10.7554/elife.67612] [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: 02/18/2021] [Accepted: 04/23/2021] [Indexed: 12/18/2022] Open
Abstract
Bones in the vertebrate cranial base and limb skeleton grow by endochondral ossification, under the control of growth plates. Mechanisms of endochondral ossification are conserved across growth plates, which increases covariation in size and shape among bones, and in turn may lead to correlated changes in skeletal traits not under direct selection. We used micro-CT and geometric morphometrics to characterize shape changes in the cranium of the Longshanks mouse, which was selectively bred for longer tibiae. We show that Longshanks skulls became longer, flatter, and narrower in a stepwise process. Moreover, we show that these morphological changes likely resulted from developmental changes in the growth plates of the Longshanks cranial base, mirroring changes observed in its tibia. Thus, indirect and non-adaptive morphological changes can occur due to developmental overlap among distant skeletal elements, with important implications for interpreting the evolutionary history of vertebrate skeletal form.
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Affiliation(s)
- Colton M Unger
- Department of Biological Sciences, University of Calgary, Calgary, Canada.,McCaig Institute for Bone and Joint Health, Calgary, Canada
| | - Jay Devine
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Canada
| | - Benedikt Hallgrímsson
- McCaig Institute for Bone and Joint Health, Calgary, Canada.,Department of Cell Biology and Anatomy, University of Calgary, Calgary, Canada.,Alberta Children's Hospital Research Institute for Child and Maternal Health, University of Calgary, Calgary, Canada
| | - Campbell Rolian
- McCaig Institute for Bone and Joint Health, Calgary, Canada.,Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Canada
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Morphology Reveals the Unexpected Cryptic Diversity in Ceratophyllus gallinae (Schrank, 1803) Infested Cyanistes caeruleus Linnaeus, 1758 Nest Boxes. Acta Parasitol 2020; 65:874-881. [PMID: 32514838 PMCID: PMC7679356 DOI: 10.1007/s11686-020-00239-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 05/29/2020] [Indexed: 11/16/2022]
Abstract
Purpose The main aim of our study was to examine morphological differentiation between and within sex of hen fleas—Ceratophyllus gallinae (Schrank, 1803) population collected from Eurasian blue tit (Cyanistes caeruleus Linnaeus, 1758), inhabiting nest boxes and to determine the morphological parameters differentiating this population. Methods A total of 296 fleas were collected (148 females and 148 males), determined to species and sex, then the following characters were measured in each of the examined fleas: body length, body width, length of head, width of head, length of comb, height of comb, length of tarsus, length of thorax and length of abdomen. Results The comparison of body size showed the presence of two groups among female and male life forms of the hen flea, which mostly differed in length of abdomen, whereas the length of head and tarsus III were less variable. Conclusion Till now, the only certain information is the presence of two adult life forms of C. gallinae. The genesis of their creation is still unknown and we are not able to identify the mechanism responsible for the morphological differentiation of fleas collected from the same host. In order to find answer to this question, future research in the field of molecular taxonomy is required.
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Frankino WA, Bakota E, Dworkin I, Wilkinson GS, Wolf JB, Shingleton AW. Individual Cryptic Scaling Relationships and the Evolution of Animal Form. Integr Comp Biol 2019; 59:1411-1428. [PMID: 31364716 PMCID: PMC6863759 DOI: 10.1093/icb/icz135] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Artificial selection offers a powerful tool for the exploration of how selection and development shape the evolution of morphological scaling relationships. An emerging approach models the expression and evolution of morphological scaling relationships as a function of variation among individuals in the developmental mechanisms that regulate trait growth. These models posit the existence of genotype-specific morphological scaling relationships that are unseen or "cryptic." Within-population allelic variation at growth-regulating loci determines how these individual cryptic scaling relationships are distributed, and exposure to environmental factors that affect growth determines the size phenotype expressed by each individual on their cryptic, genotype-specific scaling relationship. These models reveal that evolution of the intercept and slope of the population-level static allometry is determined, often in counterintuitive ways, largely by the shape of the distribution of these underlying individual-level scaling relationships. Here we review this modeling framework and present the wing-body size individual cryptic scaling relationships from a population of Drosophila melanogaster. To determine how these models might inform interpretation of published work on scaling relationship evolution, we review studies where artificial selection was applied to alter the parameters of population-level static allometries. Finally, motivated by our review, we outline areas in need of empirical work and describe a research program to address these topics; the approach includes describing the distribution of individual cryptic scaling relationships across populations and environments, empirical testing of the model's predictions, and determining the effects of environmental heterogeneity on realized trait distributions and how this affects allometry evolution.
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Affiliation(s)
- W Anthony Frankino
- Department of Biology and Biochemistry, University of Houston, Houston, TX 77204-5001, USA
| | - Eric Bakota
- Department of Biology and Biochemistry, University of Houston, Houston, TX 77204-5001, USA
| | - Ian Dworkin
- Department of Biology, McMaster University, Hamilton, Ontario, Canada L9H 6X9
| | - Gerald S Wilkinson
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Jason B Wolf
- Milner Centre for Evolution and Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK
| | - Alexander W Shingleton
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
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10
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Male Horn Lack of Allometry May be Tied to Food Relocation Behaviour in Lifting Dung Beetles (Coleoptera, Scarabaeidae, Eucraniini). INSECTS 2019; 10:insects10100359. [PMID: 31635392 PMCID: PMC6835258 DOI: 10.3390/insects10100359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 10/12/2019] [Accepted: 10/17/2019] [Indexed: 11/17/2022]
Abstract
The small dung beetle tribe Eucraniini includes extremely specialized species that have been defined as "lifters" according to their food relocation behaviour. They are characterized by the presence of well-developed expansions on the head and pronotum, which can be included in the large and varied group of horns, whose presence is usually related to complex reproductive tactics. In this study, two closely related species, Anomiopsoides cavifrons and A. heteroclyta, were examined employing traditional and geometric morphometrics to test whether the Eucraniini has polymorphic males that might exhibit different reproductive tactics, as in the sister tribe Phanaeini, for which a male trimorphism was demonstrated. If also present in Eucraniini polyphenism could be considered a plesiomorphy common to the two clades. The inter- and intraspecific shape variation and object symmetry of the head and the scaling relationships between body size and traits were evaluated. Marked interspecific and small intraspecific differences in shape variation, high symmetry, and similar isometric growth patterns were shown in both species. The hypothesis of male polymorphism in Anomiopsoides was thus rejected. Instead, the results supported the alternative hypothesis that Eucraniini lacks male polymorphism, perhaps due to functional constraints affecting the shape of the structures involved in their peculiar food relocating behaviour.
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Eberhard WG, Rodríguez RL, Huber BA, Speck B, Miller H, Buzatto BA, Machado G. Sexual Selection and Static Allometry: The Importance of Function. QUARTERLY REVIEW OF BIOLOGY 2018. [DOI: 10.1086/699410] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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12
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Malerba ME, Palacios MM, Palacios Delgado YM, Beardall J, Marshall DJ. Cell size, photosynthesis and the package effect: an artificial selection approach. THE NEW PHYTOLOGIST 2018; 219:449-461. [PMID: 29658153 DOI: 10.1111/nph.15163] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 03/08/2018] [Indexed: 06/08/2023]
Abstract
Cell size correlates with most traits among phytoplankton species. Theory predicts that larger cells should show poorer photosynthetic performance, perhaps due to reduced intracellular self-shading (i.e. package effect). Yet current theory relies heavily on interspecific correlational approaches and causal relationships between size and photosynthetic machinery have remained untested. As a more direct test, we applied 250 generations of artificial selection (c. 20 months) to evolve the green microalga Dunaliella teriolecta (Chlorophyta) toward different mean cell sizes, while monitoring all major photosynthetic parameters. Evolving larger sizes (> 1500% difference in volume) resulted in reduced oxygen production per chlorophyll molecule - as predicted by the package effect. However, large-evolved cells showed substantially higher rates of oxygen production - a finding unanticipated by current theory. In addition, volume-specific photosynthetic pigments increased with size (Chla+b), while photo-protectant pigments decreased (β-carotene). Finally, larger cells displayed higher growth performances and Fv /Fm , steeper slopes of rapid light curves (α) and smaller light-harvesting antennae (σPSII ) with higher connectivity (ρ). Overall, evolving a common ancestor into different sizes showed that the photosynthetic characteristics of a species coevolves with cell volume. Moreover, our experiment revealed a trade-off between chlorophyll-specific (decreasing with size) and volume-specific (increasing with size) oxygen production in a cell.
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Affiliation(s)
- Martino E Malerba
- Centre of Geometric Biology, School of Biological Sciences, Monash University, Melbourne, Vic., 3800, Australia
| | - Maria M Palacios
- Department of Marine Biology and Aquaculture, ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Qld, 4811, Australia
| | | | - John Beardall
- School of Biological Sciences, Monash University, Melbourne, Vic., 3800, Australia
| | - Dustin J Marshall
- Centre of Geometric Biology, School of Biological Sciences, Monash University, Melbourne, Vic., 3800, Australia
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13
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Nijhout HF, McKenna KZ. The Origin of Novelty Through the Evolution of Scaling Relationships. Integr Comp Biol 2017. [DOI: 10.1093/icb/icx049] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Perl CD, Rossoni S, Niven JE. Conservative whole-organ scaling contrasts with highly labile suborgan scaling differences among compound eyes of closely related Formica ants. Ecol Evol 2017; 7:1663-1673. [PMID: 28331577 PMCID: PMC5355196 DOI: 10.1002/ece3.2695] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 11/21/2016] [Accepted: 11/24/2016] [Indexed: 11/16/2022] Open
Abstract
Static allometries determine how organ size scales in relation to body mass. The extent to which these allometric relationships are free to evolve, and how they differ among closely related species, has been debated extensively and remains unclear; changes in intercept appear common, but changes in slope are far rarer. Here, we compare the scaling relationships that govern the structure of compound eyes of four closely related ant species from the genus Formica. Comparison among these species revealed changes in intercept but not slope in the allometric scaling relationships governing eye area, facet number, and mean facet diameter. Moreover, the scaling between facet diameter and number was conserved across all four species. In contrast, facet diameters from distinct regions of the compound eye differed in both intercept and slope within a single species and when comparing homologous regions among species. Thus, even when species are conservative in the scaling of whole organs, they can differ substantially in regional scaling within organs. This, at least partly, explains how species can produce organs that adhere to genus wide scaling relationships while still being able to invest differentially in particular regions of organs to produce specific features that match their ecology.
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Affiliation(s)
- Craig D Perl
- School of Life Sciences Centre for Computational Neuroscience and Robotics University of Sussex Falmer Brighton UK
| | - Sergio Rossoni
- School of Life Sciences Centre for Computational Neuroscience and Robotics University of Sussex Falmer Brighton UK; Present address: Department of Physiology, Development and Neuroscience University of Cambridge Downing Site, Downing Street Cambridge CB2 3EG UK
| | - Jeremy E Niven
- School of Life Sciences Centre for Computational Neuroscience and Robotics University of Sussex Falmer Brighton UK
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Malagon JN, Khan W. Evolution of allometric changes in fruit fly legs: a developmentally entrenched story. ACTA BIOLÓGICA COLOMBIANA 2016. [DOI: 10.15446/abc.v21n3.53650] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
La alometría estudia los cambios de tamaño entre las diferentes partes del cuerpo de los seres vivos y sus implicaciones ecológicas y evolutivas. Aunque la mayoría de los estudios en esta área se han centrado en investigar la importancia de los cambios alométricos en la evolución fenótipica, pocos estudios han analizado como la interconexión de los diferentes procesos del desarrollo afectan dichos cambios de tamaño. Para investigar la relación entre los mecanismos de desarrollo y los cambios alométricos, utilizamos los peines sexuales de diferentes especies del género Drosophila. Dichas estructuras, constituidas por un grupo de sedas ubicadas en las patas anteriores de los machos, presentan una variedad morfológica sobresaliente durante la evolución. Por medio de análisis morfométricos entre diferentes especies de Drosophila, incluidas líneas de Drosophila melanogaster modificadas genéticamente, investigamos los cambios alométricos que ocurren en el tamaño de las patas y diferentes tipos de sedas como resultado de la radiación de los peines sexuales. En este trabajo presentamos evidencia que sugiere una interacción compleja entre los mecanismos del desarrollo encargados de definir la distancia entre las sedas y su movimiento. Además, mostramos que dichos mecanismos son fundamentales para entender cómo evoluciona la alometría en los segmentos tarsales. Aunque la emergencia de una nueva característica puede modificar las relaciones alométricas, los procesos ancestrales de desarrollo varían en su susceptibilidad de ser modificados. De igual forma, este trabajo muestra que la interconexión entre los diferentes procesos de desarrollo puede sesgar la dirección de los cambios morfológicos.
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Dreyer AP, Saleh Ziabari O, Swanson EM, Chawla A, Frankino WA, Shingleton AW. Cryptic individual scaling relationships and the evolution of morphological scaling. Evolution 2016; 70:1703-16. [DOI: 10.1111/evo.12984] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 05/23/2016] [Accepted: 05/27/2016] [Indexed: 01/06/2023]
Affiliation(s)
- Austin P. Dreyer
- Department of Integrative Biology Michigan State University East Lansing Michigan 48824
| | | | - Eli M. Swanson
- College of Biological Sciences University of Minnesota St Paul Minnesota 55108
| | - Akshita Chawla
- Department of Statistics and Probability Michigan State University East Lansing Michigan 48824
| | - W. Anthony Frankino
- Department of Biology and Biochemistry University of Houston Houston Texas 77204
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17
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Tsuboi M, Kotrschal A, Hayward A, Buechel SD, Zidar J, Løvlie H, Kolm N. Evolution of brain-body allometry in Lake Tanganyika cichlids. Evolution 2016; 70:1559-68. [DOI: 10.1111/evo.12965] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 05/12/2016] [Accepted: 05/18/2016] [Indexed: 11/30/2022]
Affiliation(s)
- Masahito Tsuboi
- Evolutionary Biology Centre; Department of Ecology and Genetics/Animal Ecology; Uppsala University; Norbyvägen 18D SE-75236 Uppsala Sweden
| | - Alexander Kotrschal
- Department of Zoology/Ethology; Stockholm University; Svante Arrhenius väg 18B SE-10691 Stockholm Sweden
| | - Alexander Hayward
- Department of Zoology/Ethology; Stockholm University; Svante Arrhenius väg 18B SE-10691 Stockholm Sweden
| | - Severine Denise Buechel
- Department of Zoology/Ethology; Stockholm University; Svante Arrhenius väg 18B SE-10691 Stockholm Sweden
| | - Josefina Zidar
- IFM Biology; Linköping University; Campus Valla SE-58183 Linköping Sweden
| | - Hanne Løvlie
- IFM Biology; Linköping University; Campus Valla SE-58183 Linköping Sweden
| | - Niclas Kolm
- Department of Zoology/Ethology; Stockholm University; Svante Arrhenius väg 18B SE-10691 Stockholm Sweden
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Pavličev M, Cheverud JM. Constraints Evolve: Context Dependency of Gene Effects Allows Evolution of Pleiotropy. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2015. [DOI: 10.1146/annurev-ecolsys-120213-091721] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Mihaela Pavličev
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229;
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19
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Complex constraints on allometry revealed by artificial selection on the wing of Drosophila melanogaster. Proc Natl Acad Sci U S A 2015; 112:13284-9. [PMID: 26371319 DOI: 10.1073/pnas.1505357112] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Precise exponential scaling with size is a fundamental aspect of phenotypic variation. These allometric power laws are often invariant across taxa and have long been hypothesized to reflect developmental constraints. Here we test this hypothesis by investigating the evolutionary potential of an allometric scaling relationship in drosophilid wing shape that is nearly invariant across 111 species separated by at least 50 million years of evolution. In only 26 generations of artificial selection in a population of Drosophila melanogaster, we were able to drive the allometric slope to the outer range of those found among the 111 sampled species. This response was rapidly lost when selection was suspended. Only a small proportion of this reversal could be explained by breakup of linkage disequilibrium, and direct selection on wing shape is also unlikely to explain the reversal, because the more divergent wing shapes produced by selection on the allometric intercept did not revert. We hypothesize that the reversal was instead caused by internal selection arising from pleiotropic links to unknown traits. Our results also suggest that the observed selection response in the allometric slope was due to a component expressed late in larval development and that variation in earlier development did not respond to selection. Together, these results are consistent with a role for pleiotropic constraints in explaining the remarkable evolutionary stability of allometric scaling.
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de Camargo WRF, de Camargo NF, Corrêa DDCV, de Camargo AJA, Diniz IR. Sexual Dimorphism and Allometric Effects Associated With the Wing Shape of Seven Moth Species of Sphingidae (Lepidoptera: Bombycoidea). JOURNAL OF INSECT SCIENCE (ONLINE) 2015; 15:iev083. [PMID: 26206895 PMCID: PMC4672217 DOI: 10.1093/jisesa/iev083] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Accepted: 06/24/2015] [Indexed: 06/07/2023]
Abstract
Sexual dimorphism is a pronounced pattern of intraspecific variation in Lepidoptera. However, moths of the family Sphingidae (Lepidoptera: Bombycoidea) are considered exceptions to this rule. We used geometric morphometric techniques to detect shape and size sexual dimorphism in the fore and hindwings of seven hawkmoth species. The shape variables produced were then subjected to a discriminant analysis. The allometric effects were measured with a simple regression between the canonical variables and the centroid size. We also used the normalized residuals to assess the nonallometric component of shape variation with a t-test. The deformations in wing shape between sexes per species were assessed with a regression between the nonreduced shape variables and the residuals. We found sexual dimorphism in both wings in all analyzed species, and that the allometric effects were responsible for much of the wing shape variation between the sexes. However, when we removed the size effects, we observed shape sexual dimorphism. It is very common for females to be larger than males in Lepidoptera, so it is expected that the shape of structures such as wings suffers deformations in order to preserve their function. However, sources of variation other than allometry could be a reflection of different reproductive flight behavior (long flights in search for sexual mates in males, and flight in search for host plants in females).
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Affiliation(s)
- Willian Rogers Ferreira de Camargo
- Laboratório de Interação Inseto-Planta, Programa de Pós-Graduação em Zoologia, Instituto de Ciências Biológicas, Universidade de Brasília, CP 04457, Brasília, DF 70919-970, Brazil Empresa Brasileira de Pesquisa Agropecuária, Embrapa Cerrados, Coleção Entomológica, Rodovia BR 020, km 18, CP 08223, Planaltina, DF 73310-970, Brazil Corresponding author: E-mail:
| | - Nícholas Ferreira de Camargo
- Programa de Pós-Graduação em Ecologia, Instituto de Ciências Biológicas, Universidade de Brasília, CP 04457, Brasília, DF 70919-970, Brazil
| | - Danilo do Carmo Vieira Corrêa
- Centro Nacional de Pesquisa e Conservação da Biodiversidade do Cerrado e Caatinga, Instituto Chico Mendes de Conservação da Biodiversidade, EQSW 103/104, Bloco "C", Complexo Administrativo - Setor Sudoeste CEP: 70.670-350 - Brasilia - DF
| | - Amabílio J Aires de Camargo
- Empresa Brasileira de Pesquisa Agropecuária, Embrapa Cerrados, Coleção Entomológica, Rodovia BR 020, km 18, CP 08223, Planaltina, DF 73310-970, Brazil
| | - Ivone Rezende Diniz
- Laboratório de Interação Inseto-Planta, Programa de Pós-Graduação em Zoologia, Instituto de Ciências Biológicas, Universidade de Brasília, CP 04457, Brasília, DF 70919-970, Brazil
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McCauley SJ, Hammond JI, Frances DN, Mabry KE. Effects of experimental warming on survival, phenology and morphology of an aquatic insect (Odonata). ECOLOGICAL ENTOMOLOGY 2015; 40:211-220. [PMID: 26028806 PMCID: PMC4443926 DOI: 10.1111/een.12175] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
1. Organisms can respond to changing climatic conditions in multiple ways including changes in phenology, body size or morphology, and range shifts. Understanding how developmental temperatures affect insect life-history timing and morphology is crucial because body size and morphology affect multiple aspects of life history, including dispersal ability, while phenology can shape population performance and community interactions. 2. We experimentally assessed how developmental temperatures experienced by aquatic larvae affected survival, phenology, and adult morphology of dragonflies (Pachydiplax longipennis). Larvae were reared under 3 environmental temperatures: ambient, +2.5 °C, and +5 °C, corresponding to temperature projections for our study area 50 and 100 years in the future, respectively. Experimental temperature treatments tracked naturally-occurring variation. 3. We found clear effects of temperature in the rearing environment on survival and phenology: dragonflies reared at the highest temperatures had the lowest survival rates, and emerged from the larval stage approximately 3 weeks earlier than animals reared at ambient temperatures. There was no effect of rearing temperature on overall body size. Although neither the relative wing nor thorax size was affected by warming, a non-significant trend towards an interaction between sex and warming in relative thorax size suggests that males may be more sensitive to warming than females, a pattern that should be investigated further. 4. Warming strongly affected survival in the larval stage and the phenology of adult emergence. Understanding how warming in the developmental environment affects later life-history stages is critical to interpreting the consequences of warming for organismal performance.
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Affiliation(s)
- Shannon J. McCauley
- Department of Biology, University of Toronto Mississauga
- Department of Biological Sciences, California Polytechnic State University
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22
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Pélabon C, Firmat C, Bolstad GH, Voje KL, Houle D, Cassara J, Rouzic AL, Hansen TF. Evolution of morphological allometry. Ann N Y Acad Sci 2014; 1320:58-75. [DOI: 10.1111/nyas.12470] [Citation(s) in RCA: 145] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christophe Pélabon
- Department of Biology; Centre for Biodiversity Dynamics; Norwegian University of Science and Technology; Trondheim Norway
| | - Cyril Firmat
- Department of Biology; Centre for Biodiversity Dynamics; Norwegian University of Science and Technology; Trondheim Norway
| | - Geir H. Bolstad
- Department of Biology; Centre for Biodiversity Dynamics; Norwegian University of Science and Technology; Trondheim Norway
| | - Kjetil L. Voje
- Department of Biology; Centre for Ecological and Evolutionary Synthesis; University of Oslo; Oslo Norway
| | - David Houle
- Department of Biological Science; Florida State University; Tallahassee Florida
| | - Jason Cassara
- Department of Biological Science; Florida State University; Tallahassee Florida
| | - Arnaud Le Rouzic
- Laboratoire Evolution, Génomes, Spéciation; Centre National de la Recherche Scientifique; Gif-sur-Yvette France
| | - Thomas F. Hansen
- Department of Biology; Centre for Ecological and Evolutionary Synthesis; University of Oslo; Oslo Norway
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Nijhout HF, Riddiford LM, Mirth C, Shingleton AW, Suzuki Y, Callier V. The developmental control of size in insects. WILEY INTERDISCIPLINARY REVIEWS. DEVELOPMENTAL BIOLOGY 2014; 3:113-34. [PMID: 24902837 PMCID: PMC4048863 DOI: 10.1002/wdev.124] [Citation(s) in RCA: 190] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The mechanisms that control the sizes of a body and its many parts remain among the great puzzles in developmental biology. Why do animals grow to a species-specific body size, and how is the relative growth of their body parts controlled to so they grow to the right size, and in the correct proportion with body size, giving an animal its species-characteristic shape? Control of size must involve mechanisms that somehow assess some aspect of size and are upstream of mechanisms that regulate growth. These mechanisms are now beginning to be understood in the insects, in particular in Manduca sexta and Drosophila melanogaster. The control of size requires control of the rate of growth and control of the cessation of growth. Growth is controlled by genetic and environmental factors. Insulin and ecdysone, their receptors, and intracellular signaling pathways are the principal genetic regulators of growth. The secretion of these growth hormones, in turn, is controlled by complex interactions of other endocrine and molecular mechanisms, by environmental factors such as nutrition, and by the physiological mechanisms that sense body size. Although the general mechanisms of growth regulation appear to be widely shared, the mechanisms that regulate final size can be quite diverse.
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Abstract
Size-related changes of body shape were explored in 15 polymorphic species of Solenopsis fire ants by analyzing body weight along with linear measurements of 24 body parts. Log regression slopes were used to detect changes of shape with increasing size. Within species, the largest workers weighed from about 5 to 30-fold as much as the smallest. The range of within-species body lengths varied from 1.6 mm to 4 mm. As worker size increased, the gaster tended to make up a larger proportion of body length, usually at the cost of the petiole, and rarely at the cost of head length or mesosoma length. In most, the relative volume of the gaster increased and that of the head and mesosoma decreased. Most also showed an increasingly "humped" mesosoma. For all species, head shape changed from barrel-shaped to heart-shaped as worker size increased. Antennae became relatively shorter as the relative size of the club decreased. Shape changes of the legs were more variable. S. geminata was exceptional in the extreme nature of its head shape change, and was the only species in which relative head volume increased and gaster volume decreased with increasing body size. With the exception of S. geminata, the allometric rules governing shape are remarkably similar across species, suggesting a genus-level developmental scheme that is not easily modified by evolution. It also suggests that the evolution of shape is highly constrained by these conserved growth rules, and that it acts primarily (perhaps only) through allometric growth. The results are discussed in light of the growth of imaginal discs in a resource-limited body (the pupa). The substantial variation of allometries within species and across localities is also discussed in relation to using allometric patterns to identify species or to construct phylogenies.
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Affiliation(s)
- Walter R. Tschinkel
- Department of Biological Science, Florida State University, Tallahassee, Florida, United States of America
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25
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Pélabon C, Bolstad GH, Egset CK, Cheverud JM, Pavlicev M, Rosenqvist G. On the relationship between ontogenetic and static allometry. Am Nat 2013; 181:195-212. [PMID: 23348774 DOI: 10.1086/668820] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Ontogenetic and static allometries describe how a character changes in size when the size of the organism changes during ontogeny and among individuals measured at the same developmental stage, respectively. Understanding the relationship between these two types of allometry is crucial to understanding the evolution of allometry and, more generally, the evolution of shape. However, the effects of ontogenetic allometry on static allometry remain largely unexplored. Here, we first show analytically how individual variation in ontogenetic allometry and body size affect static allometry. Using two longitudinal data sets on ontogenetic and static allometry, we then estimate variances and covariances for the different parameters of the ontogenetic allometry defined in our model and assess their relative contribution to the static allometric slope. The mean ontogenetic allometry is the main parameter that determines the static allometric slope, while the covariance between the ontogenetic allometric slope and body size generates most of the discrepancies between ontogenetic and static allometry. These results suggest that the apparent evolutionary stasis of the static allometric slope is not generated by internal (developmental) constraints but more likely results from external constraints imposed by selection.
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Affiliation(s)
- Christophe Pélabon
- Centre for Conservation Biology, Department of Biology, University of Science and Technology NTNU, 7491 Trondheim, Norway.
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Voje KL, Hansen TF. EVOLUTION OF STATIC ALLOMETRIES: ADAPTIVE CHANGE IN ALLOMETRIC SLOPES OF EYE SPAN IN STALK-EYED FLIES. Evolution 2012; 67:453-67. [DOI: 10.1111/j.1558-5646.2012.01777.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Berger D, Olofsson M, Friberg M, Karlsson B, Wiklund C, Gotthard K. Intraspecific variation in body size and the rate of reproduction in female insects - adaptive allometry or biophysical constraint? J Anim Ecol 2012; 81:1244-1258. [DOI: 10.1111/j.1365-2656.2012.02010.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 05/14/2012] [Indexed: 11/26/2022]
Affiliation(s)
- David Berger
- Department of Zoology; Stockholm University; 106 91 Stockholm Sweden
- Evolutionary Biology Centre; Uppsala University; 752 36 Uppsala Sweden
| | - Martin Olofsson
- Department of Zoology; Stockholm University; 106 91 Stockholm Sweden
| | - Magne Friberg
- Department of Zoology; Stockholm University; 106 91 Stockholm Sweden
- Department of Ecology and Evolutionary Biology; University of California; Santa Cruz CA 95064 USA
| | - Bengt Karlsson
- Department of Zoology; Stockholm University; 106 91 Stockholm Sweden
| | - Christer Wiklund
- Department of Zoology; Stockholm University; 106 91 Stockholm Sweden
| | - Karl Gotthard
- Department of Zoology; Stockholm University; 106 91 Stockholm Sweden
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Nijhout HF, German RZ. Developmental causes of allometry: new models and implications for phenotypic plasticity and evolution. Integr Comp Biol 2012; 52:43-52. [PMID: 22634387 DOI: 10.1093/icb/ics068] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Shapes change during development because tissues, organs, and various anatomical features differ in onset, rate, and duration of growth. Allometry is the study of the consequences of differences in the growth of body parts on morphology, although the field of allometry has been surprisingly little concerned with understanding the causes of differential growth. The power-law equation y = ax(b), commonly used to describe allometries, is fundamentally an empirical equation whose biological foundation has been little studied. Huxley showed that the power-law equation can be derived if one assumes that body parts grow with exponential kinetics, for exactly the same amount of time. In life, however, the growth of body parts is almost always sigmoidal, and few, if any, grow for exactly the same amount of time during ontogeny. Here, we explore the shapes of allometries that result from real growth patterns and analyze them with new allometric equations derived from sigmoidal growth kinetics. We use an extensive ontogenetic dataset of the growth of internal organs in the rat from birth to adulthood, and show that they grow with Gompertz sigmoid kinetics. Gompertz growth parameters of body and internal organs accurately predict the shapes of their allometries, and that nonlinear regression on allometric data can accurately estimate the underlying kinetics of growth. We also use these data to discuss the developmental relationship between static and ontogenetic allometries. We show that small changes in growth kinetics can produce large and apparently qualitatively different allometries. Large evolutionary changes in allometry can be produced by small and simple changes in growth kinetics, and we show how understanding the development of traits can greatly simplify the interpretation of how they evolved.
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EGSET CK, HANSEN TF, LE ROUZIC A, BOLSTAD GH, ROSENQVIST G, PÉLABON C. Artificial selection on allometry: change in elevation but not slope. J Evol Biol 2012; 25:938-48. [DOI: 10.1111/j.1420-9101.2012.02487.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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30
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Olson ME. The developmental renaissance in adaptationism. Trends Ecol Evol 2012; 27:278-87. [PMID: 22326724 DOI: 10.1016/j.tree.2011.12.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Revised: 12/01/2011] [Accepted: 12/31/2011] [Indexed: 11/16/2022]
Abstract
From an adaptation perspective, unoccupied patches of morphological space are inferred to be empty because they are of low fitness and selected against. These inferences hinge on venturesome assumptions, because emptiness is explained by low fitness and low fitness is inferred from emptiness. Moreover, non-adaptive factors, such as developmental constraint, could also plausibly account for empty morphospace. In response, biologists increasingly study ontogeny to test the assumption that unobserved phenotypes could be produced if selection were to favor them; finding that empty space morphologies can be readily produced in development helps reject constraint and lends support to adaptive hypotheses. This developmental approach to adaptation calls on manifold techniques, including embryology, artificial selection and comparative methods. Belying their diversity, all of these methods examine the causes of empty morphospace and mark a return of development, long excluded from traditional evolutionary biology, to adaptationist practice.
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Affiliation(s)
- Mark E Olson
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de México, Tercer Circuito de Ciudad Universitaria, México DF 04510, Mexico.
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