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Cited by 11Photonic Crystals and ApplicationsOptical Coatings and Gratingsmelanin and skin pigmentation

Light diffraction by sarcomeres produces iridescence in transmission in the transparent ghost catfish

Open access
Fan, Xiujun, Zheng, Xuezhi, An, Tong, Li, Xiuhong, Leung, Nathanael, Zhu, Bin, Sui, Tan, Shi, Nan +2 more·2023·Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.2219300120PMC PMC10041080
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Abstract

Despite the elaborate varieties of iridescent colors in biological species, most of them are reflective. Here we show the rainbow-like structural colors found in the ghost catfish ( Kryptopterus vitreolus ), which exist only in transmission. The fish shows flickering iridescence throughout the transparent body. The iridescence originates from the collective diffraction of light after passing through the periodic band structures of the sarcomeres inside the tightly stacked myofibril sheets, and the muscle fibers thus work as transmission gratings. The length of the sarcomeres varies from ~1 μm from the body neutral plane near the skeleton to ~2 μm next to the skin, and the iridescence of a live fish mainly results from the longer sarcomeres. The length of the sarcomere changes by ~80 nm as it relaxes and contracts, and the fish shows a quickly blinking dynamic diffraction pattern as it swims. While similar diffraction colors are also observed in thin slices of muscles from non-transparent species such as the white crucian carps, a transparent skin is required indeed to have such iridescence in live species. The ghost catfish skin is of a plywood structure of collagen fibrils, which allows more than 90% of the incident light to pass directly into the muscles and the diffracted light to exit the body. Our findings could also potentially explain the iridescence in other transparent aquatic species, including the eel larvae ( Leptocephalus ) and the icefishes (Salangidae).

AI snapshot

Written from the paper’s full text.

TL;DR

The transparent ghost catfish shows rainbow-like iridescence in transmission, produced by light diffraction from periodic sarcomeres in its axial and fin-support muscles rather than by surface reflection. The transparent skin protects the body and allows most visible light to pass, while muscle contraction and relaxation dynamically shift the diffraction colors as the fish swims.

Key findings

  • The iridescence originates from sarcomere diffraction in transmission: muscle fibers act as transmission gratings, and the skin is an optically lossless protective film; the diffraction patterns show clear 0, ±first, and ±second orders.
  • Sarcomere length increases from ~1.1 μm next to the skeleton to ~2.0 μm next to the body surface; live-fish iridescence is mainly contributed by longer sarcomeres close to the surface, with equivalent sarcomere lengths of ~1.4 μm and ~1.9 μm for muscles cut next to bone and next to skin, respectively.
  • Dynamic color change tracks muscle activity: at rest, sarcomere length was calculated as ~1,863 nm relaxed and ~1,786 nm contracted, a change of ~80 nm and strain ε ~4%; in a swimming fish, diffraction colors disappeared and reappeared periodically at an interval of ~0.07 s.
  • The skin is ~20 μm thick, lacks scales, guanine crystals, and pigments, and has transmittance of ~93.4% at 800 nm, ~86.2% at 400 nm, and ~50% at 300 nm; M1 iridescence is visible horizontally between approximately 40° and −40°, while M2 iridescence is visible vertically.

Methods

  • Adult ghost catfish (Kryptopterus vitreolus) were acquired from the aquarium market, reared at 26 °C, killed with clove oil, rinsed in 0.1 M PBS, and fixed with 2.5% glutaraldehyde; skin and muscle samples were separated after fixation.
  • Optical measurements used a supercontinuum white light laser and a 532 nm Nd:YAG laser, with diffraction spectra measured by a goniometer setup and spectrometer from −80° to 80° in 2° steps; transmission spectra used a UV-VIS-NIR spectrometer with an integration sphere.
  • Structural characterization used SEM, TEM, and SAXS at the BL10U1 USAXS beamline at SSRF with 10 keV photons; diffraction was modeled with Fraunhofer diffraction, simplified at normal incidence as λ = p/sinθ, where p is sarcomere period.

Limitations

  • The paper states that the biological functions of the iridescence “have not been properly investigated yet,” and that camouflage or communication roles need further studies.
  • The paper states that the reason live-fish diffraction is dominated by longer sarcomeres, despite sarcomere lengths varying from ~1 μm to 2 μm, “needs further studies.”
  • Evident from the text: functional claims about camouflage and communication are speculative and untested; the study focuses mainly on M1 and M2 because M3 is limited in size, and it examines one species rather than testing the proposed functions experimentally.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1073/pnas.2219300120

Cites

33 of 33 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

11 of 16 cited sources checked · 5 supported · 1 flagged · accuracy not yet measured

  • Premisecitation

    Structural colors in fish usually result from reflection by guanine crystals inside the scales or skin.

    “Indeed, structural colors in fish are not rare, but the colors usually result from the reflection by guanine crystals inside the scales or skin (21, 22), which are obviously missing in the transparent species.”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [21] T. M. Jordan, J. C. Partridge, N. W. Roberts, Non-polarizing broadband multilayer reflectors in fish. Nat. Photonics 6, 759– 763 (2012). 23160173 PMC3496938 source

      The passage on fish reflectors (section labeled Abstract; page unavailable) says silvery reflections come from guanine-crystal stacks and that many fish have these stacks in the skin or on the inner surface of scales. It does not establish that structural colors in fish generally or usually arise this way; its discussion is specifically about silvery reflectors. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [22] D. Gur, The mechanism of color change in the neon tetra fish: A light-induced tunable photonic crystal array. Angew. Chem. Int. Ed. Engl. 54, 12426– 12430 (2015). 25914222 source
  • Findingcitation

    In the transverse direction, the myosin myofilaments are assembled in ordered hexagonal lattices.

    “In the transverse direction, the myosin myofilaments are assembled in ordered hexagonal lattices (SI Appendix, Fig. S25) (32).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [32] K. Ojima, Myosin: Formation and maintenance of thick filaments. Anim. Sci. J. 90, 801– 807 (2019). 31134719 PMC6618170 source

      The Introduction sections on myofibril structure and myosin assembly describe a highly ordered sarcomere and organized myosin thick filaments. They do not describe the filaments’ transverse arrangement as a hexagonal lattice (searched: “hexagonal lattice transverse thick filaments” and “hexagonal”). The reference to a myosin molecule as a hexamer concerns its components, not its lattice arrangement. Page numbers were unavailable in our copy. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
  • Interpretationcitation

    The difference in density generates a periodic variation in refractive index along the axial direction of the myofibrils.

    “The difference in density thus generates a periodic variation in refractive index along the axial direction of the myofibrils (Fig. 3B) (31).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [31] K. W. Young, S. Radic, E. Myslivets, S. M. O’Connor, R. L. Lieber, Resonant reflection spectroscopy of biomolecular arrays in muscle. Biophys. J. 107, 2352– 2360 (2014). 25418304 PMC4241457 source
  • Interpretationcitation

    The muscle fiber can be considered as a grating structure of regularly separated bands.

    “Since both the electron microscope and SAXS results show that the muscle fiber is highly ordered along the axial direction, and the periodicity is decided by the band structure of the sarcomere, thus it can be considered as a grating structure of regularly separated bands (31)”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [31] K. W. Young, S. Radic, E. Myslivets, S. M. O’Connor, R. L. Lieber, Resonant reflection spectroscopy of biomolecular arrays in muscle. Biophys. J. 107, 2352– 2360 (2014). 25418304 PMC4241457 source
  • Premisecitation

    The Z-line and M-line are where myofilaments are entangled with particularly higher density.

    “The Z-line and M-line are where the myofilaments are entangled of particularly higher density (Fig. 3A) (30).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [30] L. Burbaum, Molecular-scale visualization of sarcomere contraction within native cardiomyocytes. Nat. Commun. 12, 1– 12 (2021). 34215727 PMC8253822 source

      In ‘Visualizing the myofibrillar interior in situ’ (page unavailable), the paper describes Z-disks as densely packed structures with high density. In ‘Structural signature of sarcomere contraction’ (page unavailable), it reports filament overlap at two of three M-lines, but says it did not observe a significant increase in thin-filament number in those regions. The claim’s higher-density characterization of the M-line is therefore not supported. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
  • May combine two claims. 17
  • Classified as probably not a substantial claim. 12

  • May combine two claims.

    Premisecitation

    Transparent wings of insects exhibit iridescent colors in reflection yet are colorless in transmission.

    “A typical example is the transparent wings of insects (10), which exhibit iridescent colors in reflection yet are colorless in transmission.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [10] E. Shevtsova, C. Hansson, D. H. Janzen, J. Kjærandsen, Stable structural color patterns displayed on transparent insect wings. Proc. Natl. Acad. Sci. U.S.A. 108, 668– 673 (2011). 21199954 PMC3021046 source

      The paper reports colored reflections from transparent insect wings, but explicitly describes their patterns as stable and essentially noniridescent (p. 1). The Discussion (p. 3) says it finds almost no iridescence except under narrowly directed light, contrary to the citing sentence’s unqualified description of iridescent colors in reflection. (LLM, conf=0.93)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured

  • Classified as probably not a substantial claim.

    Premisecitation

    Most iridescent colorations in biology originate from intricate photonic structures in the surface that reflect selected wavelengths of incident light outwardly.

    “Most iridescent colorations in biology originate from the intricate photonic structures in the surface (5–9), which reflect selected wavelengths of the incident light outwardly.”
    Quote in the paperSubstantial claim3 of 5 sources checked
    • cites [5] S. Vignolini, Pointillist structural color in Pollia fruit. Proc. Natl. Acad. Sci. U.S.A. 109, 15712– 15715 (2012). 23019355 PMC3465391 source
    • cites [6] E. Moyroud, Disorder in convergent floral nanostructures enhances signalling to bees. Nature 550, 469– 474 (2017). 29045384 source
    • cites [7] J. Zi, Coloration strategies in peacock feathers. Proc. Natl. Acad. Sci. U.S.A. 100, 12576– 12578 (2003). 14557541 PMC240659 source

      The introduction describes structural coloration in nature, and Results and Discussion explains how a photonic structure in peacock feathers reflects particular frequencies and produces iridescence. The paper does not establish that this mechanism accounts for most iridescent coloration across biology. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [8] J. T. Bagnara, P. J. Fernandez, R. Fujii, On the blue coloration of vertebrates. Pigment Cell Res. 20, 14– 26 (2007). 17250544 source
    • cites [9] V. Welch, J. P. Vigneron, V. Lousse, A. Parker, Optical properties of the iridescent organ of the comb-jellyfish Beroë cucumis (Ctenophora). Phys. Rev. E Stat. Nonlin. Soft Matter Phys. 73, 1– 7 (2006). 16711845 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The myofibril is comprised of thick myosin myofilaments and thin actin myofilaments.

    “The myofibril is comprised of the thick myosin myofilaments and thin actin myofilaments (29)”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [29] E. Brunello, Myosin filament-based regulation of the dynamics of contraction in heart muscle. Proc. Natl. Acad. Sci. U.S.A. 117, 8177– 8186 (2020). 32220962 PMC7149498 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    The ghost catfish has a fast contractive muscle (white muscle) structure typical in fish species.

    “The ghost catfish shows a fast contractive muscle (white muscle) structure typical in fish species (Fig. 2 B and C) (28).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [28] A. F. Mead, G. G. Kennedy, B. M. Palmer, A. M. Ebert, D. M. Warshaw, Mechanical characteristics of ultrafast zebrafish larval swimming muscles. Biophys. J. 119, 806– 820 (2020). 32755560 PMC7451861 source

      The Results (p. 9) describe fast-twitch muscle fibers with an ultrastructure typical of vertebrate striated muscle, and the Figure 2 caption (p. 10) details their structure. But the paper studies zebrafish larvae, not ghost catfish, so it does not establish the claim about ghost catfish muscle. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Findingown data

    When white light is illuminated on one side of the ghost catfish body, it shows strong iridescence on the other side with little reflection.

    “When white light is illuminated on one side of the body, it shows strong iridescence on the other side with little reflection (Fig. 1B and SI Appendix, Fig. S1).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The separated ghost catfish skin is a freestanding transparent film with only sparse melanin pigments close to the dorsal side.

    “The separated skin is a freestanding transparent film with only sparse melanin pigments close to the dorsal side (SI Appendix, Fig. S14).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    At normal incidence, the iridescence of M2 is visible vertically and invisible horizontally.

    “At normal incidence, the iridescence of M1 is visible in transmission between approximately 40° and −40° in the horizontal plane and invisible in the vertical plane (SI Appendix, Figs. S3–S13), while the iridescence of M2 is visible vertically and invisible horizontally.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    At normal incidence, the iridescence of M1 is visible in transmission between approximately 40° and −40° in the horizontal plane and invisible in the vertical plane.

    “At normal incidence, the iridescence of M1 is visible in transmission between approximately 40° and −40° in the horizontal plane and invisible in the vertical plane (SI Appendix, Figs. S3–S13), while the iridescence of M2 is visible vertically and invisible horizontally.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The muscle fibers of the ghost catfish have irregular polygonal transverse cross-sections with varying diameters on the scale of tens to 100 μm.

    “The muscle fibers are of irregular polygonal transverse cross-sections with varying diameters on the scale of tens to 100 µm (Fig. 2D and SI Appendix, Fig. S23).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    In the ghost catfish, no other muscle types except white muscle have been found so far.

    “in the ghost catfish so far we have not found any other muscle types except the white muscle.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The vector distance Δq between the SAXS diffraction spots is ~0.00788 nm−1 in reciprocal space, which equals 0.797 μm in real space.

    “The vector distance Δq between the SAXS diffraction spots is ~0.00788 nm−1 in reciprocal space, which equals to 0.797 μm in real space (Fig. 2F)”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    At relaxed state, the length of the sarcomere was calculated to be ~1,863 nm, which was shortened to 1,786 nm as it contracted.

    “At relaxed state, the length of the sarcomere was calculated to be ~ 1,863 nm, which was shortened to 1,786 nm as it contracted.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    The time interval of the sarcomere relaxation and contraction of the fish that was at rest is obviously much longer than that of the fish swimming in water.

    “The time interval of the sarcomere relaxation and contraction of the fish that was at rest is also obviously much longer than that of the fish swimming in water.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The spectra of transmitted light from −80° to 80° of a live fish show clear 0, ±first, and ±second diffraction signals, which fits well with simulation results using p = 1.9 μm.

    “The spectra of the transmitted light from −80° to 80° of a live fish were measured with a step of 2°, showing clear 0, ±first, and ±second diffraction signals, which fits well with the simulation results using p = 1.9 μm.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Diffractions from sarcomeres of distinct length are particularly obvious in the diffraction patterns of the shrimp muscle.

    “diffractions from sarcomeres of distinct length are particularly obvious in the diffraction patterns of the shrimp muscle”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The myosin and actin myofilaments are co-assembled into striated structures known as sarcomeres, repeating over the entire length of the muscle fiber with a uniform period.

    “which are co-assembled into striated structures known as the sarcomeres (Fig. 3 A and B), repeating over the entire length of the muscle fiber with a uniform period.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Findingnone given

    The ultrathin skin of the ghost catfish allows more than 90% of the light to enter and exit the body.

    “the ultrathin skin of the ghost catfish allows more than 90% of the light to enter and exit the body.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Many aquatic species share white muscles of similar structures.

    “Many aquatic species share white muscles of similar structures”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The distance from S01 and S02 to the center is 0.026 nm−1 and 0.046 nm−1, respectively, giving d01= 38.22 nm, d02 = 21.58 nm, and d02/d01 = 0.564, close to 0.577 in the ideal hexagonal lattice.

    “The distance from S01 and S02 to the center is 0.026 nm−1 and 0.046 nm−1, respectively, giving d01= 38.22 nm, d02 = 21.58 nm, and d02/d01 = 0.564, close to that of 0.577 in the ideal hexagonal lattice.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The measured diffraction spectra of muscles cut from next to the bones and next to the skin show clear differences in the diffraction angles of the first and second orders, and the equivalent sarcomere length is ~1.4 μm and 1.9 μm, respectively.

    “The measured diffraction spectra of the muscles cut from next to the bones and next to the skin show clear differences in the diffraction angles of the first and second orders (Fig. 3E), and the equivalent sarcomere length is ~1.4 μm and 1.9 μm, respectively.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The change of the sarcomere length is ~80 nm, thus the strain of a single sarcomere in relaxation or contraction is ε ~ 4%.

    “The change of the sarcomere length is ~80 nm, thus the strain of a single sarcomere in relaxation or contraction is ε ~ 4%”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    SAXS on stained samples shows the structure factor of the muscle fibers, indicating structural periodicity along the axial direction of the muscle fibers.

    “By using small-angle X-ray scattering (SAXS) on stained samples (Fig. 2F), the structure factor of the muscle fibers is obtained, which clearly shows the structural periodicity along the axial direction of the muscle fibers.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    The extreme transparency of the ghost catfish skin enables most incident light to enter the body and diffracted light to exit.

    “Although many other species such as the white crucian carps and white shrimps share similar muscle structures with the ghost catfish, the key difference is that the ghost catfish skin is extremely transparent, which enables most of the incident light to enter the body and the diffracted light to exit.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Many other species such as white crucian carps and white shrimps share similar muscle structures with the ghost catfish.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In aquatic species, the length of the sarcomere changes as it differentiates during growth.

    “In aquatic species, the length of the sarcomere changes as it differentiates during growth (33).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [33] H. A. Akster, Ultrastructure of muscle fibres in head and axial muscles of the perch (Perca fluviatilis L)–A quantitative study. Cell Tissue Res. 219, 111– 131 (1981). 7285089 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Transmission of air was taken as a reference for transmission spectra measurements.

    “Transmission of air was taken as a reference.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    A small strain in the sarcomere may generate large deflections of the body depending on how many muscle fibers are used, which has a much more significant influence on the diffracted colors as seen in the swimming fish than simply the length change of the sarcomere as in the fish that was kept still.

    “Therefore, a small strain in the sarcomere may generate large deflections of the body depending on how many muscle fibers are used, which has a much more significant influence on the diffracted colors as seen in the swimming fish than simply the length change of the sarcomere as in the fish that was kept still.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Background scans for SAXS measurements were taken by measuring scattering in air without samples.

    “Background scans were taken by measuring scattering in air without samples.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    The shrimp body does not show iridescence due to both the lack of a transparent skin and the stronger scattering from the much thicker body.

    “although their bodies do not show iridescence due to both the lack of a transparent skin and the stronger scattering from the much thicker body (SI Appendix, Text).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The q-range for SAXS measurements was calibrated using fiber diffraction of dry beef tendon.

    “The q-range is calibrated using fiber diffraction of dry beef tendon.”
    Quote in the paperNot a substantial claim
29 of 29

  • The paper relies on this without support.

    The physical origin of the circumstantial iridescence in transparent aquatic species such as the ghost catfish was unknown.

    “but the origin is still unknown.”

  • The paper relies on this without support.

    No living species was known to use inwardly transmitted light to produce iridescence.

    “Whether there exists any living species that uses inwardly transmitted light to produce iridescence remains unknown.”

  • The paper relies on this without support.

    Many other species such as white crucian carps and white shrimps share similar muscle structures with the ghost catfish.

    “Although many other species such as the white crucian carps and white shrimps share similar muscle structures with the ghost catfish, the key difference is that the ghost catfish skin is extremely transparent, which enables most of the incident light to enter the body and the diffracted light to exit.”

  • The paper relies on this without support.

    The biological functions of the iridescence of the ghost catfish have not been properly investigated yet.

    “The biological functions of the iridescence of the ghost catfish have not been properly investigated yet.”

  • The paper relies on this without support.

    The same type of muscle is shared by many other aquatic species.

    “Although the same type of muscle is shared by many other aquatic species”

  • The paper relies on this without support.

    Other aquatic species lack a transparent skin.

    “they lack of a transparent skin”
6 of 6

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Simplified diffraction equation contradicts the general equation

    Minor

    At normal incidence, with a first-order diffraction angle and an exit-medium refractive index of 1, the stated general equation makes wavelength proportional to the sine of the exit angle (λ = p sinθ, up to the sign convention). The stated simplification instead divides p by sinθ, so it cannot follow from the paper's own equation.

1 of 1

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. 10.1098/rstb.2016.0341 · DOI

Cited by

Sorted by citations

Related

Authors
Fan, X., Zheng, X., An, T., Li, X., Leung, N., Zhu, B., Sui, T., Shi, N., Fan, T., & Zhao, Q.
Affiliations
  • Shanghai Jiao Tong University (CN)
  • KU Leuven (BE)
  • Shanghai Synchrotron Radiation Facility (CN)
  • University of Surrey (GB)
Corresponding author
  • Shi, Nan
  • Fan, Tongxiang
  • Zhao, Qibin
ORCID
Venue
Proceedings of the National Academy of Sciences
Publisher
National Academy of Sciences
Published
2023-03-13
Volume
120
Issue
12
Pages
e2219300120-e2219300120
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
DOI
10.1073/pnas.2219300120
PMC
PMC10041080
OpenAlex
W4324028668
Semantic Scholar
b08c791fdf758665e1784aa0f596dd2197872132
Cited by
11
References
33
Citations by year
2026: 3 · 2025: 3 · 2024: 3 · 2023: 2
FWCI
1.27
Type
journal article
Language
en
Open access
Licence
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion, cc-by-nc-nd)
  • PubMed Central (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
  • Lirias (submittedVersion, cc-by-nc-nd)
Funders
  • National Natural Science Foundation of China (51903155 51802191 52011530182)
  • Shanghai Rising-Star Program (21QA1404700)
  • Royal Society (IEC\NSFC\191003)
Topics
  • Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Photonic Crystals and Applications
  • Physical Sciences › Materials Science › Surfaces, Coatings and Films › Optical Coatings and Gratings
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › melanin and skin pigmentation
Keywords
structural color, iridescence, sarcomere, light diffraction, transmission gratings, myofibrils, collagen fibrils, muscle contraction, leptocephalus, icefish, Salangidae
MeSH terms
Iridescence, Animals, Catfishes, Myofibrils, Sarcomeres, Swimming

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Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-11-02.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-11-02.

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