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Finet C. Developmental genetics of cuticular micro- and nano-structures in insects. CURRENT OPINION IN INSECT SCIENCE 2024; 65:101254. [PMID: 39182719 DOI: 10.1016/j.cois.2024.101254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2024] [Revised: 08/13/2024] [Accepted: 08/20/2024] [Indexed: 08/27/2024]
Abstract
Insect cuticle exhibits a wide array of micro- and nano-structures in terms of size, form, and function. However, the investigation of cellular mechanisms of morphogenesis has centered around a small number of structure types and organisms. The recent expansion of the taxa studied, and subsequent discoveries prompt us to revisit well-known models, like the one for bristle morphogenesis. In addition, common themes are emerging in the morphogenesis of cuticular structures, such as the polyploidy of precursor cells, the role of pigments and cuticular proteins in controlling chitin deposition in space and time, and the role of the apical extracellular matrix in defining the shape of the developing structure. Understanding how these structures are synthesized in biological systems holds promise for bioinspired design.
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Affiliation(s)
- Cédric Finet
- Department of Biological Sciences, National University of Singapore, Singapore.
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2
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Jessop AL, Pirih P, Wang L, Patel NH, Clode PL, Schröder-Turk GE, Wilts BD. Elucidating nanostructural organization and photonic properties of butterfly wing scales using hyperspectral microscopy. J R Soc Interface 2024; 21:20240185. [PMID: 39257280 DOI: 10.1098/rsif.2024.0185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/03/2024] [Accepted: 08/02/2024] [Indexed: 09/12/2024] Open
Abstract
Biophotonic nanostructures in butterfly wing scales remain fascinating examples of biological functional materials, with intriguing open questions with regard to formation and evolutionary function. One particularly interesting butterfly species, Erora opisena (Lycaenidae: Theclinae), develops wing scales that contain three-dimensional photonic crystals that closely resemble a single gyroid geometry. Unlike most other gyroid-forming butterflies, E. opisena develops discrete gyroid crystallites with a pronounced size gradient hinting at a developmental sequence frozen in time. Here, we present a novel application of a hyperspectral (wavelength-resolved) microscopy technique to investigate the ultrastructural organization of these gyroid crystallites in dry, adult wing scales. We show that reflectance corresponds to crystallite size, where larger crystallites reflect green wavelengths more intensely; this relationship could be used to infer size from the optical signal. We further successfully resolve the red-shifted reflectance signal from wing scales immersed in refractive index liquids with varying refractive index, including values similar to water or cytosol. Such photonic crystals with lower refractive index contrast may be similar to the hypothesized nanostructural forms in the developing butterfly scales. The ability to resolve these fainter signals hints at the potential of this facile light microscopy method for in vivo analysis of nanostructure formation in developing butterflies.
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Affiliation(s)
- Anna-Lee Jessop
- School of Mathematics, Statistics, Chemistry and Physics, Murdoch University , Perth, Western Australia 6150, Australia
| | - Primož Pirih
- Department of Chemistry and Physics of Materials, University of Salzburg , Salzburg 5020, Austria
| | - Limin Wang
- Department of Chemistry and Physics of Materials, University of Salzburg , Salzburg 5020, Austria
| | - Nipam H Patel
- Marine Biological Laboratory, University of Chicago , Woods Hole, MA 02543, USA
| | - Peta L Clode
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia , Perth, Western Australia 6009, Australia
- School of Biological Sciences, University of Western Australia , Perth, Western Australia 6009, Australia
| | - Gerd E Schröder-Turk
- School of Mathematics, Statistics, Chemistry and Physics, Murdoch University , Perth, Western Australia 6150, Australia
- Research School of Physics, The Australian National University , Canberra, Australian Capital Territory 2601, Australia
| | - Bodo D Wilts
- Department of Chemistry and Physics of Materials, University of Salzburg , Salzburg 5020, Austria
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3
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Lloyd VJ, Burg SL, Harizanova J, Garcia E, Hill O, Enciso-Romero J, Cooper RL, Flenner S, Longo E, Greving I, Nadeau NJ, Parnell AJ. The actin cytoskeleton plays multiple roles in structural colour formation in butterfly wing scales. Nat Commun 2024; 15:4073. [PMID: 38769302 PMCID: PMC11106069 DOI: 10.1038/s41467-024-48060-3] [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: 10/18/2023] [Accepted: 04/19/2024] [Indexed: 05/22/2024] Open
Abstract
Vivid structural colours in butterflies are caused by photonic nanostructures scattering light. Structural colours evolved for numerous biological signalling functions and have important technological applications. Optically, such structures are well understood, however insight into their development in vivo remains scarce. We show that actin is intimately involved in structural colour formation in butterfly wing scales. Using comparisons between iridescent (structurally coloured) and non-iridescent scales in adult and developing H. sara, we show that iridescent scales have more densely packed actin bundles leading to an increased density of reflective ridges. Super-resolution microscopy across three distantly related butterfly species reveals that actin is repeatedly re-arranged during scale development and crucially when the optical nanostructures are forming. Furthermore, actin perturbation experiments at these later developmental stages resulted in near total loss of structural colour in H. sara. Overall, this shows that actin plays a vital and direct templating role during structural colour formation in butterfly scales, providing ridge patterning mechanisms that are likely universal across lepidoptera.
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Affiliation(s)
- Victoria J Lloyd
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Alfred Denny Building, Western bank, Sheffield, S10 2TN, UK.
| | - Stephanie L Burg
- Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield, S3 7RH, UK
| | - Jana Harizanova
- Central Laser Facility-Science & Technology Facility Council, The Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire, OX11 0FA, UK
- Core Facility for Integrated Microscopy, Department of Biomedical Sciences, University of Copenhagen, 2200N, Copenhagen, Denmark
| | - Esther Garcia
- Central Laser Facility-Science & Technology Facility Council, The Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire, OX11 0FA, UK
| | - Olivia Hill
- Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield, S3 7RH, UK
| | - Juan Enciso-Romero
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Alfred Denny Building, Western bank, Sheffield, S10 2TN, UK
- Department of Biological Sciences, University of Lethbridge, 4401 University Drive, Lethbridge, AB, T1K 3M4, Canada
| | - Rory L Cooper
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Alfred Denny Building, Western bank, Sheffield, S10 2TN, UK
- Department of Genetics and Evolution, University of Geneva, Sciences III, Geneva, 1205, Switzerland
| | - Silja Flenner
- Helmholtz-Zentrum Hereon, Max-Planck-Strasse 1, 21502, Geesthacht, Germany
| | - Elena Longo
- Elettra-Sincrotrone Trieste S.C.p.A., 34149, Basovizza, Trieste, Italy
| | - Imke Greving
- Helmholtz-Zentrum Hereon, Max-Planck-Strasse 1, 21502, Geesthacht, Germany
| | - Nicola J Nadeau
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Alfred Denny Building, Western bank, Sheffield, S10 2TN, UK.
| | - Andrew J Parnell
- Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield, S3 7RH, UK.
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4
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Thayer RC, Patel NH. A meta-analysis of butterfly structural colors: their color range, distribution and biological production. J Exp Biol 2023; 226:jeb245940. [PMID: 37937662 DOI: 10.1242/jeb.245940] [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: 11/09/2023]
Abstract
Butterfly scales are among the richest natural sources of optical nanostructures, which produce structural color and iridescence. Several recurring nanostructure types have been described, such as ridge multilayers, gyroids and lower lamina thin films. While the optical mechanisms of these nanostructure classes are known, their phylogenetic distributions and functional ranges have not been described in detail. In this Review, we examine a century of research on the biological production of structural colors, including their evolution, development and genetic regulation. We have also created a database of more than 300 optical nanostructures in butterflies and conducted a meta-analysis of the color range, abundance and phylogenetic distribution of each nanostructure class. Butterfly structural colors are ubiquitous in short wavelengths but extremely rare in long wavelengths, especially red. In particular, blue wavelengths (around 450 nm) occur in more clades and are produced by more kinds of nanostructures than other hues. Nanostructure categories differ in prevalence, phylogenetic distribution, color range and brightness. For example, lamina thin films are the least bright; perforated lumen multilayers occur most often but are almost entirely restricted to the family Lycaenidae; and 3D photonic crystals, including gyroids, have the narrowest wavelength range (from about 450 to 550 nm). We discuss the implications of these patterns in terms of nanostructure evolution, physical constraint and relationships to pigmentary color. Finally, we highlight opportunities for future research, such as analyses of subadult and Hesperid structural colors and the identification of genes that directly build the nanostructures, with relevance for biomimetic engineering.
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Affiliation(s)
- Rachel C Thayer
- Department of Evolution and Ecology, University of California, Davis, Davis, CA 95616, USA
| | - Nipam H Patel
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
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5
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Seah KS, Saranathan V. Hierarchical morphogenesis of swallowtail butterfly wing scale nanostructures. eLife 2023; 12:RP89082. [PMID: 37768710 PMCID: PMC10538957 DOI: 10.7554/elife.89082] [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] [Indexed: 09/29/2023] Open
Abstract
The study of color patterns in the animal integument is a fundamental question in biology, with many lepidopteran species being exemplary models in this endeavor due to their relative simplicity and elegance. While significant advances have been made in unraveling the cellular and molecular basis of lepidopteran pigmentary coloration, the morphogenesis of wing scale nanostructures involved in structural color production is not well understood. Contemporary research on this topic largely focuses on a few nymphalid model taxa (e.g., Bicyclus, Heliconius), despite an overwhelming diversity in the hierarchical nanostructural organization of lepidopteran wing scales. Here, we present a time-resolved, comparative developmental study of hierarchical scale nanostructures in Parides eurimedes and five other papilionid species. Our results uphold the putative conserved role of F-actin bundles in acting as spacers between developing ridges, as previously documented in several nymphalid species. Interestingly, while ridges are developing in P. eurimedes, plasma membrane manifests irregular mesh-like crossribs characteristic of Papilionidae, which delineate the accretion of cuticle into rows of planar disks in between ridges. Once the ridges have grown, disintegrating F-actin bundles appear to reorganize into a network that supports the invagination of plasma membrane underlying the disks, subsequently forming an extruded honeycomb lattice. Our results uncover a previously undocumented role for F-actin in the morphogenesis of complex wing scale nanostructures, likely specific to Papilionidae.
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Affiliation(s)
- Kwi Shan Seah
- Division of Science, Yale-NUS CollegeSingaporeSingapore
- Department of Biological Science, National University of SingaporeSingaporeSingapore
| | - Vinodkumar Saranathan
- Division of Science, Yale-NUS CollegeSingaporeSingapore
- Department of Biological Science, National University of SingaporeSingaporeSingapore
- NUS Nanoscience and Nanotechnology Initiative (NUSNNI-NanoCore), National University of SingaporeSingaporeSingapore
- Lee Kong Chian Natural History Museum, National University of SingaporeSingaporeSingapore
- Present Address: Division of Sciences, School of Interwoven Arts and Sciences, Krea University, Central ExpresswaySri CityIndia
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6
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Hanly JJ, Loh LS, Mazo-Vargas A, Rivera-Miranda TS, Livraghi L, Tendolkar A, Day CR, Liutikaite N, Earls EA, Corning OBWH, D'Souza N, Hermina-Perez JJ, Mehta C, Ainsworth JA, Rossi M, Papa R, McMillan WO, Perry MW, Martin A. Frizzled2 receives WntA signaling during butterfly wing pattern formation. Development 2023; 150:dev201868. [PMID: 37602496 PMCID: PMC10560568 DOI: 10.1242/dev.201868] [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: 04/12/2023] [Accepted: 08/04/2023] [Indexed: 08/22/2023]
Abstract
Butterfly color patterns provide visible and biodiverse phenotypic readouts of the patterning processes. Although the secreted ligand WntA has been shown to instruct the color pattern formation in butterflies, its mode of reception remains elusive. Butterfly genomes encode four homologs of the Frizzled-family of Wnt receptors. Here, we show that CRISPR mosaic knockouts of frizzled2 (fz2) phenocopy the color pattern effects of WntA loss of function in multiple nymphalids. Whereas WntA mosaic clones result in intermediate patterns of reduced size, fz2 clones are cell-autonomous, consistent with a morphogen function. Shifts in expression of WntA and fz2 in WntA crispant pupae show that they are under positive and negative feedback, respectively. Fz1 is required for Wnt-independent planar cell polarity in the wing epithelium. Fz3 and Fz4 show phenotypes consistent with Wnt competitive-antagonist functions in vein formation (Fz3 and Fz4), wing margin specification (Fz3), and color patterning in the Discalis and Marginal Band Systems (Fz4). Overall, these data show that the WntA/Frizzled2 morphogen-receptor pair forms a signaling axis that instructs butterfly color patterning and shed light on the functional diversity of insect Frizzled receptors.
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Affiliation(s)
- Joseph J. Hanly
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
- Smithsonian Tropical Research Institute, Gamboa 0843-03092, Panama
| | - Ling S. Loh
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
| | - Anyi Mazo-Vargas
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
| | | | - Luca Livraghi
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
- Smithsonian Tropical Research Institute, Gamboa 0843-03092, Panama
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Amruta Tendolkar
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
| | - Christopher R. Day
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, Durham, NC 27708, USA
| | - Neringa Liutikaite
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
| | - Emily A. Earls
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
| | - Olaf B. W. H. Corning
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
| | - Natalie D'Souza
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
| | - José J. Hermina-Perez
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
| | - Caroline Mehta
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
| | - Julia A. Ainsworth
- Department of Cell and Developmental Biology, UC San Diego, La Jolla, CA, USA
| | - Matteo Rossi
- Division of Evolutionary Biology, Ludwig Maximilian University, Munich 80539, Germany
| | - Riccardo Papa
- Department of Biology, University of Puerto Rico at Río Piedras, San Juan 00931, Puerto Rico
- Molecular Sciences and Research Center, University of Puerto Rico, San Juan 00931, Puerto Rico
- Dipartimento di Scienze Chimiche della Vita e della Sostenibilità Ambientale, Università di Parma, Parma 43121, Italy
| | - W. Owen McMillan
- Smithsonian Tropical Research Institute, Gamboa 0843-03092, Panama
| | - Michael W. Perry
- Department of Cell and Developmental Biology, UC San Diego, La Jolla, CA, USA
| | - Arnaud Martin
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA
- Smithsonian Tropical Research Institute, Gamboa 0843-03092, Panama
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7
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Nakazato Y, Otaki JM. Live Detection of Intracellular Chitin in Butterfly Wing Epithelial Cells In Vivo Using Fluorescent Brightener 28: Implications for the Development of Scales and Color Patterns. INSECTS 2023; 14:753. [PMID: 37754721 PMCID: PMC10532232 DOI: 10.3390/insects14090753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 09/01/2023] [Accepted: 09/07/2023] [Indexed: 09/28/2023]
Abstract
Chitin is the major component of the extracellular cuticle and plays multiple roles in insects. In butterflies, chitin builds wing scales for structural colors. Here, we show that intracellular chitin in live cells can be detected in vivo with fluorescent brightener 28 (FB28), focusing on wing epithelial cells of the small lycaenid butterfly Zizeeria maha immediately after pupation. A relatively small number of cells at the apical surface of the epithelium were strongly FB28-positive in the cytosol and seemed to have extensive ER-Golgi networks, which may be specialized chitin-secreting cells. Some cells had FB28-positive tadpole-tail-like or rod-like structures relative to the nucleus. We detected FB28-positive hexagonal intracellular objects and their associated structures extending toward the apical end of the cell, which may be developing scale bases and shafts. We also observed FB28-positive fibrous intracellular structures extending toward the basal end. Many cells were FB28-negative in the cytosol, which contained FB28-positive dots or discs. The present data are crucial to understanding the differentiation of the butterfly wing epithelium, including scale formation and color pattern determination. The use of FB28 in probing intracellular chitin in live cells may be applicable to other insect systems.
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Affiliation(s)
| | - Joji M. Otaki
- The BCPH Unit of Molecular Physiology, Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Okinawa 903-0213, Japan
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8
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Tang CF, Li FF, Cao Y, Liao HJ. Universal cooling patterns of the butterfly wing scales hierarchy deduced from the heterogeneous thermal and structural properties of Tirumala limniace (Lepidoptera: Nymphalidae, Danainae). INSECT SCIENCE 2022; 29:1761-1772. [PMID: 35452162 DOI: 10.1111/1744-7917.13046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 03/03/2022] [Accepted: 03/30/2022] [Indexed: 06/14/2023]
Abstract
The radiative cooling of butterfly wing scales hierarchy has great value in understanding how poikilotherms adapt to the environment and developing bionic materials. However, it remains unclear what the cooling system is like and how the variation of hierarchy affects the cooling efficiency. Therefore, the correlation between the variations of the structure and emissivity of scale hierarchy is thoroughly investigated in Tirumala limniace (Cramer, 1775), whose thermal properties are highly heterogeneous among different wings and regions but similar between males and females. Patterns were deduced from the biological and model simulation experiments. The scale hierarchy varies at the micro- to nanolevel on both surface and section, corresponding to the variating emissivity. Scales on wing veins and margins have large nanostructured units with small lumens and are distinctly thickened, which bring extraordinarily high emissivity. The variations of light and dark scales, respectively, lead to the high emissivity of the middle region of wings and the front wings. Generally, the elevation of the inner surface area and the thickness of the chitin is the key to enhancing the cooling efficiency. For the first time, the effects of the variation of hierarchy toward emissivity of the mid-infrared spectrum are systematically clarified. It is demonstrated that wing scales integrally differentiate in coping with the heterogeneous cooling needs, which may benefit in balancing multifunctions and the development toward the adaptation to the abiotic environment. The study provides insights into the comprehensive thermoregulation system of butterflies and the further development of radiative cooling materials.
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Affiliation(s)
- Chu-Fei Tang
- Institute of Leisure Agriculture, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Fan-Fan Li
- Institute of Leisure Agriculture, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Ye Cao
- Institute of Leisure Agriculture, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Huai-Jian Liao
- Institute of Leisure Agriculture, Jiangsu Academy of Agricultural Sciences, Nanjing, China
- Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Affairs, Shanghai, China
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9
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Antennapedia and optix regulate metallic silver wing scale development and cell shape in Bicyclus anynana butterflies. Cell Rep 2022; 40:111052. [PMID: 35793633 DOI: 10.1016/j.celrep.2022.111052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 05/06/2022] [Accepted: 06/14/2022] [Indexed: 12/29/2022] Open
Abstract
Butterfly wing scales can develop intricate cuticular nanostructures that produce silver colors, but the underlying genetic and physical basis of such colors is mostly unexplored. Here, we characterize different types of wild-type silver scales in Bicyclus anynana butterflies and show that the varying thickness of the air layer between two cuticular laminas is most important for producing silvery broadband reflectance. We then address the function of five genes-apterous A, Ultrabithorax, doublesex, Antennapedia, and optix-in silver scale development by examining crispants with either ectopic gains or losses of silver scales. Simultaneous transformations of three parameters-loss of the upper lamina, increased lower lamina thickness, and increased pigmentation-occur when silver scales become brown and vice versa when brown scales become silver. Antennapedia and optix are high-level regulators of different silver scale types and determine cell shape in both sexes. Moreover, Antennapedia is involved in determining ridge and crossrib orientation.
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10
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Dyba K, Wąsala R, Piekarczyk J, Gabała E, Gawlak M, Jasiewicz J, Ratajkiewicz H. Reflectance spectroscopy and machine learning as a tool for the categorization of twin species based on the example of the Diachrysia genus. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 273:121058. [PMID: 35220048 DOI: 10.1016/j.saa.2022.121058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/11/2022] [Accepted: 02/14/2022] [Indexed: 06/14/2023]
Abstract
In our work we used noninvasive point reflectance spectroscopy in the range from 400 to 2100 nm coupled with machine learning to study scales on the brown and golden iridescent areas on the dorsal side of the forewing of Diachrysia chrysitis and D. stenochrysis. We used our approach to distinguish between these species of moths. The basis for the study was a statistically significant collection of 95 specimens identified based on morphological feature and gathered during 23 years in Poland. The numerical part of an experiment included two independent discriminant analyses: stochastic and deterministic. The more sensitive stochastic approach achieved average compliance with the species identification made by entomologists at the level of 99-100%. It demonstrated high stability against the different configurations of training and validation sets, hence strong predictors of Diachrysia siblings distinctiveness. Both methods resulted in the same small set of relevant features, where minimal fully discriminating subsets of wavelengths were three for glass scales on the golden area and four for the brown. The differences between species in scales primarily concern their major components and ultrastructure. In melanin-absent glass scales, this is mainly chitin configuration, while in melanin-present brown scales, melanin reveals as an additional factor.
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Affiliation(s)
- Krzysztof Dyba
- Institute of Geoecology and Geoinformation, Adam Mickiewicz University in Poznań, Poland
| | - Roman Wąsala
- Department of Entomology and Environment Protection, Poznań University of Life Sciences, Poland
| | - Jan Piekarczyk
- Institute of Physical Geography and Environmental Planning, Adam Mickiewicz University in Poznań, Poland
| | - Elżbieta Gabała
- Research Centre of Quarantine, Invasive and Genetically Modified Organisms, Institute of Plant Protection - National Research Institute, Poland
| | - Magdalena Gawlak
- Research Centre of Quarantine, Invasive and Genetically Modified Organisms, Institute of Plant Protection - National Research Institute, Poland
| | - Jarosław Jasiewicz
- Institute of Geoecology and Geoinformation, Adam Mickiewicz University in Poznań, Poland.
| | - Henryk Ratajkiewicz
- Department of Entomology and Environment Protection, Poznań University of Life Sciences, Poland.
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11
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In vivo visualization of butterfly scale cell morphogenesis in Vanessa cardui. Proc Natl Acad Sci U S A 2021; 118:2112009118. [PMID: 34845021 PMCID: PMC8670486 DOI: 10.1073/pnas.2112009118] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/11/2021] [Indexed: 12/12/2022] Open
Abstract
Many organisms exhibit functional micro- and nanoscale materials with structural definition and performance that challenge synthetic fabrication techniques, yet we know little about the processes that enable their formation. Using butterfly scales as a model system for functional biomaterials, we establish a timeline of scale formation and quantify relevant structural parameters for developing painted lady butterflies. We overcome challenges of previous efforts by imaging structure formation directly in living organisms, which allows us to continuously observe the evolving wing tissue and the fine details of individual scale cells. Visualization of scale structure formation in live butterflies forms the basis for modeling the underlying biomechanical processes and opens avenues for their translation into advanced fabrication strategies. During metamorphosis, the wings of a butterfly sprout hundreds of thousands of scales with intricate microstructures and nano-structures that determine the wings’ optical appearance, wetting characteristics, thermodynamic properties, and aerodynamic behavior. Although the functional characteristics of scales are well known and prove desirable in various applications, the dynamic processes and temporal coordination required to sculpt the scales’ many structural features remain poorly understood. Current knowledge of scale growth is primarily gained from ex vivo studies of fixed scale cells at discrete time points; to fully understand scale formation, it is critical to characterize the time-dependent morphological changes throughout their development. Here, we report the continuous, in vivo, label-free imaging of growing scale cells of Vanessa cardui using speckle-correlation reflection phase microscopy. By capturing time-resolved volumetric tissue data together with nanoscale surface height information, we establish a morphological timeline of wing scale formation and gain quantitative insights into the underlying processes involved in scale cell patterning and growth. We identify early differences in the patterning of cover and ground scales on the young wing and quantify geometrical parameters of growing scale features, which suggest that surface growth is critical to structure formation. Our quantitative, time-resolved in vivo imaging of butterfly scale development provides the foundation for decoding the processes and biomechanical principles involved in the formation of functional structures in biological materials.
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12
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Piszter G, Kertész K, Sramkó G, Krízsik V, Bálint Z, Biró LP. Concordance of the spectral properties of dorsal wing scales with the phylogeographic structure of European male Polyommatus icarus butterflies. Sci Rep 2021; 11:16498. [PMID: 34389765 PMCID: PMC8363635 DOI: 10.1038/s41598-021-95881-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 07/28/2021] [Indexed: 11/24/2022] Open
Abstract
The males of more than 80% of the Lycaenidae species belonging to the tribe Polyommatini exhibit structural coloration on their dorsal wing surfaces. These colors have a role in reinforcement in prezygotic reproductive isolation. The species-specific colors are produced by the cellular self-assembly of chitin/air nanocomposites. The spectral position of the reflectance maximum of such photonic nanoarchitectures depends on the nanoscale geometric dimensions of the elements building up the nanostructure. Previous work showed that the coloration of male Polyommatus icarus butterflies in the Western and Eastern Palearctic exhibits a characteristic spectral difference (20 nm). We investigated the coloration and the de novo developed DNA microsatellites of 80 P. icarus specimens from Europe from four sampling locations, spanning a distance of 1621 km. Remarkably good concordance was found between the spectral properties of the blue sexual signaling color (coincident within 5 nm) and the population genetic structure as revealed by 10 microsatellites for the P. icarus species.
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Affiliation(s)
- Gábor Piszter
- Institute of Technical Physics and Materials Science, Centre for Energy Research, P.O. Box 49, 1525, Budapest, Hungary.
| | - Krisztián Kertész
- Institute of Technical Physics and Materials Science, Centre for Energy Research, P.O. Box 49, 1525, Budapest, Hungary
| | - Gábor Sramkó
- MTA-DE "Lendület" Evolutionary Phylogenomics Research Group, 1 Egyetem Sq., 4032, Debrecen, Hungary
| | - Virág Krízsik
- Department of Zoology, Hungarian Natural History Museum, 13 Baross St., 1088, Budapest, Hungary
| | - Zsolt Bálint
- Institute of Technical Physics and Materials Science, Centre for Energy Research, P.O. Box 49, 1525, Budapest, Hungary
- Department of Zoology, Hungarian Natural History Museum, 13 Baross St., 1088, Budapest, Hungary
| | - László Péter Biró
- Institute of Technical Physics and Materials Science, Centre for Energy Research, P.O. Box 49, 1525, Budapest, Hungary
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13
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Livraghi L, Hanly JJ, Van Bellghem SM, Montejo-Kovacevich G, van der Heijden ESM, Loh LS, Ren A, Warren IA, Lewis JJ, Concha C, Hebberecht L, Wright CJ, Walker JM, Foley J, Goldberg ZH, Arenas-Castro H, Salazar C, Perry MW, Papa R, Martin A, McMillan WO, Jiggins CD. Cortex cis-regulatory switches establish scale colour identity and pattern diversity in Heliconius. eLife 2021; 10:e68549. [PMID: 34280087 PMCID: PMC8289415 DOI: 10.7554/elife.68549] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 06/14/2021] [Indexed: 12/14/2022] Open
Abstract
In Heliconius butterflies, wing colour pattern diversity and scale types are controlled by a few genes of large effect that regulate colour pattern switches between morphs and species across a large mimetic radiation. One of these genes, cortex, has been repeatedly associated with colour pattern evolution in butterflies. Here we carried out CRISPR knockouts in multiple Heliconius species and show that cortex is a major determinant of scale cell identity. Chromatin accessibility profiling and introgression scans identified cis-regulatory regions associated with discrete phenotypic switches. CRISPR perturbation of these regions in black hindwing genotypes recreated a yellow bar, revealing their spatially limited activity. In the H. melpomene/timareta lineage, the candidate CRE from yellow-barred phenotype morphs is interrupted by a transposable element, suggesting that cis-regulatory structural variation underlies these mimetic adaptations. Our work shows that cortex functionally controls scale colour fate and that its cis-regulatory regions control a phenotypic switch in a modular and pattern-specific fashion.
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Affiliation(s)
- Luca Livraghi
- Department of Zoology, University of Cambridge, Downing St.CambridgeUnited Kingdom
- Smithsonian Tropical Research InstituteGamboaPanama
| | - Joseph J Hanly
- Department of Zoology, University of Cambridge, Downing St.CambridgeUnited Kingdom
- Smithsonian Tropical Research InstituteGamboaPanama
- The George Washington University Department of Biological Sciences, Science and Engineering HallWashingtonUnited States
| | - Steven M Van Bellghem
- Department of Biology, Centre for Applied Tropical Ecology and Conservation, University of Puerto RicoRio PiedrasPuerto Rico
| | | | - Eva SM van der Heijden
- Department of Zoology, University of Cambridge, Downing St.CambridgeUnited Kingdom
- Smithsonian Tropical Research InstituteGamboaPanama
| | - Ling Sheng Loh
- The George Washington University Department of Biological Sciences, Science and Engineering HallWashingtonUnited States
| | - Anna Ren
- The George Washington University Department of Biological Sciences, Science and Engineering HallWashingtonUnited States
| | - Ian A Warren
- Department of Zoology, University of Cambridge, Downing St.CambridgeUnited Kingdom
| | - James J Lewis
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell UniversityIthacaUnited States
| | | | - Laura Hebberecht
- Department of Zoology, University of Cambridge, Downing St.CambridgeUnited Kingdom
- Smithsonian Tropical Research InstituteGamboaPanama
| | - Charlotte J Wright
- Department of Zoology, University of Cambridge, Downing St.CambridgeUnited Kingdom
| | - Jonah M Walker
- Department of Zoology, University of Cambridge, Downing St.CambridgeUnited Kingdom
| | | | - Zachary H Goldberg
- Cell & Developmental Biology, Division of Biological Sciences, UC San DiegoLa JollaUnited States
| | | | - Camilo Salazar
- Biology Program, Faculty of Natural Sciences, Universidad del RosarioBogotáColombia
| | - Michael W Perry
- Cell & Developmental Biology, Division of Biological Sciences, UC San DiegoLa JollaUnited States
| | - Riccardo Papa
- Department of Biology, Centre for Applied Tropical Ecology and Conservation, University of Puerto RicoRio PiedrasPuerto Rico
| | - Arnaud Martin
- The George Washington University Department of Biological Sciences, Science and Engineering HallWashingtonUnited States
| | | | - Chris D Jiggins
- Department of Zoology, University of Cambridge, Downing St.CambridgeUnited Kingdom
- Smithsonian Tropical Research InstituteGamboaPanama
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14
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Pomerantz AF, Siddique RH, Cash EI, Kishi Y, Pinna C, Hammar K, Gomez D, Elias M, Patel NH. Developmental, cellular and biochemical basis of transparency in clearwing butterflies. J Exp Biol 2021; 224:268372. [PMID: 34047337 PMCID: PMC8340268 DOI: 10.1242/jeb.237917] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 04/16/2021] [Indexed: 12/16/2022]
Abstract
The wings of butterflies and moths (Lepidoptera) are typically covered with thousands of flat, overlapping scales that endow the wings with colorful patterns. Yet, numerous species of Lepidoptera have evolved highly transparent wings, which often possess scales of altered morphology and reduced size, and the presence of membrane surface nanostructures that dramatically reduce reflection. Optical properties and anti-reflective nanostructures have been characterized for several ‘clearwing’ Lepidoptera, but the developmental processes underlying wing transparency are unknown. Here, we applied confocal and electron microscopy to create a developmental time series in the glasswing butterfly, Greta oto, comparing transparent and non-transparent wing regions. We found that during early wing development, scale precursor cell density was reduced in transparent regions, and cytoskeletal organization during scale growth differed between thin, bristle-like scale morphologies within transparent regions and flat, round scale morphologies within opaque regions. We also show that nanostructures on the wing membrane surface are composed of two layers: a lower layer of regularly arranged nipple-like nanostructures, and an upper layer of irregularly arranged wax-based nanopillars composed predominantly of long-chain n-alkanes. By chemically removing wax-based nanopillars, along with optical spectroscopy and analytical simulations, we demonstrate their role in generating anti-reflective properties. These findings provide insight into morphogenesis and composition of naturally organized microstructures and nanostructures, and may provide bioinspiration for new anti-reflective materials. Summary: Transparency is a fascinating, yet poorly studied, optical property in living organisms. We elucidated the developmental processes underlying scale and nanostructure formation in glasswing butterflies, and their roles in generating anti-reflective properties.
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Affiliation(s)
- Aaron F Pomerantz
- Department of Integrative Biology, University of California, Berkeley, Berkeley, CA 94720, USA.,Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Radwanul H Siddique
- Image Sensor Lab, Samsung Semiconductor, Inc., 2 N Lake Ave. Ste. 240, Pasadena, CA 91101, USA.,Department of Medical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Elizabeth I Cash
- Department of Environmental Science, Policy, & Management, University of California Berkeley, Berkeley, CA 94720, USA
| | - Yuriko Kishi
- Department of Molecular & Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.,Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Charline Pinna
- ISYEB, 45 rue Buffon, CP50, 75005, Paris, CNRS, MNHN, Sorbonne Université, EPHE, Université des Antilles, France
| | - Kasia Hammar
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Doris Gomez
- CEFE, 1919 route de Mende, 34090, Montpellier, CNRS, Université Montpellier, Université Paul Valéry Montpellier 3, EPHE, IRD, France
| | - Marianne Elias
- ISYEB, 45 rue Buffon, CP50, 75005, Paris, CNRS, MNHN, Sorbonne Université, EPHE, Université des Antilles, France
| | - Nipam H Patel
- Department of Integrative Biology, University of California, Berkeley, Berkeley, CA 94720, USA.,Marine Biological Laboratory, Woods Hole, MA 02543, USA.,Department of Molecular & Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
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15
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Liu J, Chen Z, Xiao Y, Asano T, Li S, Peng L, Chen E, Zhang J, Li W, Zhang Y, Tong X, Kadono-Okuda K, Zhao P, He N, Arunkumar KP, Gopinathan KP, Xia Q, Willis JH, Goldsmith MR, Mita K. Lepidopteran wing scales contain abundant cross-linked film-forming histidine-rich cuticular proteins. Commun Biol 2021; 4:491. [PMID: 33888855 PMCID: PMC8062583 DOI: 10.1038/s42003-021-01996-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 03/18/2021] [Indexed: 02/02/2023] Open
Abstract
Scales are symbolic characteristic of Lepidoptera; however, nothing is known about the contribution of cuticular proteins (CPs) to the complex patterning of lepidopteran scales. This is because scales are resistant to solubilization, thus hindering molecular studies. Here we succeeded in dissolving developing wing scales from Bombyx mori, allowing analysis of their protein composition. We identified a distinctive class of histidine rich (His-rich) CPs (6%-45%) from developing lepidopteran scales by LC-MS/MS. Functional studies using RNAi revealed CPs with different histidine content play distinct and critical roles in constructing the microstructure of the scale surface. Moreover, we successfully synthesized films in vitro by crosslinking a 45% His-rich CP (BmorCPR152) with laccase2 using N-acetyl- dopamine or N-β-alanyl-dopamine as the substrate. This molecular study of scales provides fundamental information about how such a fine microstructure is constructed and insights into the potential application of CPs as new biomaterials.
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Affiliation(s)
- Jianqiu Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Biological Science Research Center, Southwest University, Chongqing, China
| | - Zhiwei Chen
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Yingdan Xiao
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Biological Science Research Center, Southwest University, Chongqing, China
| | - Tsunaki Asano
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo, Japan
| | - Shenglong Li
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Li Peng
- Shanghai Center for Plant Stress Biology and Center of Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Enxiang Chen
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Biological Science Research Center, Southwest University, Chongqing, China
| | - Jiwei Zhang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Wanshun Li
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Biological Science Research Center, Southwest University, Chongqing, China
| | - Yan Zhang
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Biological Science Research Center, Southwest University, Chongqing, China
| | - Xiaoling Tong
- Biological Science Research Center, Southwest University, Chongqing, China
| | - Keiko Kadono-Okuda
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
| | - Ping Zhao
- Biological Science Research Center, Southwest University, Chongqing, China
| | - Ningjia He
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
| | - Kallare P Arunkumar
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China
- Biological Science Research Center, Southwest University, Chongqing, China
- Central Muga Eri Research and Training Institute, (CMER&TI), Central Silk Board, Jorhat, India
| | | | - Qingyou Xia
- Biological Science Research Center, Southwest University, Chongqing, China
| | - Judith H Willis
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
| | - Marian R Goldsmith
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
- Biological Science Research Center, Southwest University, Chongqing, China.
- Department of Biological Sciences, University of Rhode Island, Kingston, RI, USA.
| | - Kazuei Mita
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
- Biological Science Research Center, Southwest University, Chongqing, China.
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16
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The evolution of structural colour in butterflies. Curr Opin Genet Dev 2021; 69:28-34. [PMID: 33540167 DOI: 10.1016/j.gde.2021.01.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/21/2020] [Accepted: 01/01/2021] [Indexed: 01/23/2023]
Abstract
Butterflies display some of the most striking examples of structural colour in nature. These colours originate from cuticular scales that cover the wing surface, which have evolved a diverse suite of optical nanostructures capable of manipulating light. In this review we explore recent advances in the evolution of structural colour in butterflies. We discuss new insights into the underlying genetics and development of the structural colours in various nanostructure types. Improvements in -omic and imaging technologies have been paramount to these new advances and have permitted an increased appreciation of their development and evolution.
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17
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Actin bundles play a different role in shaping scales compared to bristles in the mosquito Aedes aegypti. Sci Rep 2020; 10:14885. [PMID: 32913276 PMCID: PMC7483531 DOI: 10.1038/s41598-020-71911-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 08/21/2020] [Indexed: 11/25/2022] Open
Abstract
Insect epithelial cells contain cellular extensions such as bristles, hairs, and scales. These cellular extensions are homologous structures that differ in morphology and function. They contain actin bundles that dictate their cellular morphology. While the organization, function, and identity of the major actin-bundling proteins in bristles and hairs are known, this information on scales is unknown. In this study, we characterized the development of scales and the role of actin bundles in the mosquito, Aedes aegypti. We show that scales undergo drastic morphological changes during development, from a cylindrical to flat shape with longer membrane invagination. Scale actin-bundle distribution changes from the symmetrical organization of actin bundles located throughout the bristle membrane to an asymmetrical organization. By chemically inhibiting actin polymerization and by knocking out the forked gene in the mosquito (Ae-Forked; a known actin-bundling protein) by CRISPR-Cas9 gene editing, we showed that actin bundles are required for shaping bristle, hair, and scale morphology. We demonstrated that actin bundles and Ae-Forked are required for bristle elongation, but not for that of scales. In scales, actin bundles are required for width formation. In summary, our results reveal, for the first time, the developmental process of mosquito scale formation and also the role of actin bundles and actin-bundle proteins in scale morphogenesis. Moreover, our results reveal that although scale and bristle are thought to be homologous structures, actin bundles have a differential requirement in shaping mosquito scales compared to bristles.
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18
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Ren A, Day CR, Hanly JJ, Counterman BA, Morehouse NI, Martin A. Convergent Evolution of Broadband Reflectors Underlies Metallic Coloration in Butterflies. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00206] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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19
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Boppré M, Fischer OW, Freitag H, Kiesel A. 'Crystal Macrosetae': Novel Scales and Bristles in Male Arctiine Moths (Lepidoptera: Erebidae: Arctiinae) Filled with Crystallizing Material. JOURNAL OF INSECT SCIENCE (ONLINE) 2019; 19:5607538. [PMID: 31665785 PMCID: PMC6821358 DOI: 10.1093/jisesa/iez099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Indexed: 06/10/2023]
Abstract
Scales, exoskeletal features characteristic of the Lepidoptera, occur in enormous structural and functional diversity. They cover the wing membranes and other body parts and give butterflies and moths their often stunning appearance. Generally, the patterns made by scales are visual signals for intra- and interspecific communication. In males, scales and/or bristles also make up the androconial organs, which emit volatile signals during courtship. Here, a structurally and putative functionally novel type of scales and bristles is reported: 'crystal macrosetae'. These lack trabeculae and windows, are made up by a very thin and flexible envelope only and contain crystallizing material. In 'crystal scales', there is a flat surface ornamentation of modified ridges, while 'crystal bristles' often show large protrusions. Crystal macrosetae usually cannot be reliably recognized without destruction. Apparently, they serve as containers for large amounts of material that is viscous in living moths, highly hygroscopic, crystallizes when specimens dry up, and can be visualized by scanning electron microscopy. Crystal macrosetae occur in males only, always associated with or making up androconial organs located on various parts of the body, and have numerous forms with diverse surface ornamentation across many species and genera. The newly identified structures and the discovery of crystallizing material in scales and bristles raise many questions and could shed new light on ontogenetic development of macrosetae, and on the biology and physiology as well as the evolution and systematics of Arctiinae. There is evidence that crystal macrosetae occur in other moths too.
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Affiliation(s)
- Michael Boppré
- Forstzoologie und Entomologie, Albert-Ludwigs-Universität, Freiburg i.Br., Germany
| | - Ottmar W Fischer
- Forstzoologie und Entomologie, Albert-Ludwigs-Universität, Freiburg i.Br., Germany
| | - Hannes Freitag
- Forstzoologie und Entomologie, Albert-Ludwigs-Universität, Freiburg i.Br., Germany
| | - Anita Kiesel
- Forstzoologie und Entomologie, Albert-Ludwigs-Universität, Freiburg i.Br., Germany
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20
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Franz-Odendaal TA, Hockman D. Non-model organisms and unique approaches are needed for the future of evo-devo. Dev Dyn 2019; 248:618-619. [PMID: 31215704 DOI: 10.1002/dvdy.71] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
| | - Dorit Hockman
- Division of Cell Biology, Department of Human Biology, Neuroscience Institute, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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