Differential Spectral Adaptation in Praying Mantises

Differential Spectral Adaptation in Praying Mantises | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Differential Spectral Adaptation in Praying Mantises Ruchao Qian, Jamie C. Theobald, Tamara M. Frank This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6816664/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 08 Nov, 2025 Read the published version in Journal of Comparative Physiology A → Version 1 posted 9 You are reading this latest preprint version Abstract Praying mantises often display elaborate camouflage, disappearing into the shapes, textures, and colors around them. But they have largely been thought to be monochromats, unable to perceive the colors they mimic. To examine this, we tested the compound eye spectral sensitivity of three species of praying mantises, each representing unique mimicry strategies: Theopropus elegans , Popa spurca , and Hymenopus coronatus . We quantified mantis sensitivity to light, ranging from 350 to 650 nm wavelength, using electroretinograms under both dark and chromatic adaptation. We find distinct sensitivity peaks that suggest the presence of multiple photoreceptor types or varying expressions of visual pigments across the species studied. T. elegans and P. spurca exhibited potential trichromatic vision, with primary sensitivity peaks in green (515–520 nm), and secondary and tertiary peaks in ultraviolet (340–360 nm) and blue (442 nm and 413 nm). Conversely, H. coronatus displayed a simpler dichromatic pattern. This suggests praying mantises have the capacity for color vision, likely adapted to enhance camouflage and predatory efficiency in their environments. Figures Figure 1 Figure 2 Figure 3 Introduction Among the order Mantodea, most species have evolved remarkable camouflage, merging exquisitely with specific elements such as flowers, leaves, and branches, to evade predators and ambush prey. But despite functioning in spectrally rich habitats, they have long been thought to be colorblind (Sontag 1971 ; Fabricant and Herberstein 2014 ; Kral and Prete 2004 ). Previous studies on mantis spectral sensitivity are limited, with only one notable study by Sontag ( 1971 ) suggesting that the praying mantis, Tenodera sinensis , might be monochromatic, though findings were not definitive. However, color vision may be important for locating appropriate habitats that minimize detectability. To test this, we used electroretinograms (ERG) to measure the compound eye spectral sensitivities of 3 praying mantis species, representing different mimicry strategies and dwelling habitats (Fig. 1 a-c). Theopropus elegans , the banded flower mantis (Xishuangbanna population), resides in flowers where body color blends seamlessly with the floral environment, enabling them to feed on pollinators. Popa spurca , the African twig mantis, inhabits bushes or branches where their twig-like appearance provides camouflage. Hymenopus coronatus , the orchid mantis, also preys on pollinators but lives on green leaves, aggressively mimicking the appearance of a flower. The survival of each relies on inhabiting the correct environment, which would be challenging without color vision. Visual ecology of a species is often highly specialized to maximize efficiency in natural habitats (Chittka and Briscoe 2001 ; Forward et al. 1988 ; van der Kooi et al. 2021 ), and mantises offer a further opportunity to explore the relationship between their camouflage strategies and visual capabilities, as these strategies are closely tied to their ecological roles and dwelling habitats. However, the camouflage strategies of the three mantis species in this study have not yet been scientifically validated. To address this, we measured wing reflectance spectra and the body morphometric of these mantises to characterize their camouflage objectively. We predicted that all three species would possess more than one visual pigment, with sensitivity peaks corresponding to wavelengths abundant or relevant to their specific habitats. In particular, we expected T. elegans and H. coronatus , both associated with flowers, to exhibit heightened sensitivity to ultraviolet (UV) light and reflect UV wavelengths, as many flowers show contrasting UV patterns to attract pollinators (Narbona et al. 2021 ). Material and methods Animal maintenance We bred all animals in captivity under a 12:12-hour light-dark cycle in the laboratory. Each mantis consumed one appropriately sized feeder cockroach every two days. We used only adult females from all three species. To ensure dark adaptation, we kept mantises in complete darkness for three days prior to ERG experiments. The laboratory was maintained at a constant 23°C. Reflectance measurement We used a spectrometer (QE Pro, Ocean Optics) to measure the spectral reflectance of adult female mantis wings over a 350–650 nm wavelength range. Prior to measurements, we calibrated the spectrometer using polytetrafluoroethylene (PTFE) as a white standard. We positioned a full-spectrum light source (LS-1, Ocean Optics, Inc., Dunedin, FL, USA) at 45° toward the wing, with the spectrometer detecting probe 1 cm away, perpendicular to the wing surface at the point of measurement. Each measurement had an exposure time of 2 seconds, and reflectance curves represented the average normalized values from 3 randomly chosen points on each wing. Morphometric Measurement We performed morphometric measurements to quantify the morphology of the mantis body region primarily covered by the wings. Specifically, we measured three anatomical dimensions: (1) mesothoraco-abdominal length, defined as the distance from the anterior edge of the mesoscutum to the posterior tip of the abdomen, (2) maximum body width, measured as the widest lateral extent of the mesothoraco-abdominal region, and (3) maximum body height, determined as the greatest dorsoventral distance within this region. To minimize variation due to abdominal swelling in gravid individuals, all measurements were performed 6–10 days after adult emergence, before the significant development of ovaries. We then calculated and plotted body shape ratios of height-to-width and mesothoraco-abdominal length-to-width. Electrophysiology We adopted our electrophysiological recording method from Frank et al. ( 2012 ), with the equipment apparatus replicated from Qian and Frank ( 2024 ). ERGs measure the collective electrical response of photoreceptor cells to light (Autrum 1948 ), which can bypass the pre-retinal filtering effect and provide a direct measurement of spectral sensitivity. Mantises were dark-adapted for at least three days prior to recording, and all animal preparations were conducted under dim red light to avoid unintended visual adaptation. We secured animals inside a Faraday cage covered with a light-proof sheet in a dark room. With a micromanipulator and a dissecting microscope (Olympus), we inserted a glass-insulated tungsten microelectrode (Frederick Haer) into the dorsal region of the eye, resting its tip directly above the photoreceptor layer. We placed a silver chloride reference electrode on top of the untested eye to eliminate electrical noise from the body. After placing the electrode, we allowed mantises to dark adapt for 1–2 hours. We delivered stimuli using a 150 W quartz halogen lamp source coupled to a monochromator (CM110, Spectral Products) and guided via a bifurcated light guide cable (EXFO). We positioned the end of the light guide approximately 1 cm from the eye surface, oriented perpendicularly to the insertion site, which illuminated roughly 10% of the eye's visual field. We amplified recording signals with an X Cell-3 Microelectrode Amplifier (FHC, Inc.) with a high impedance probe. We set the amplification level to 2000X and applied filters between 1 and 1000 Hz. At the beginning of the recording, we flashed a 490 nm wavelength at an initially dim irradiance of 10 8 photons cm − 2 s − 1 , then gradually increased the irradiance until the flash-elicited response stabilized at 50µV. Measurements began once the response to the adjusted test flash remained constant for one hour. In the dark-adapted experiment, we stimulated the eye with monochromatic light flashes, adjusting flash irradiance to elicit a criterion response of 100 µV (or higher if the response was indistinguishable from background noise). Each flash lasted 0.1 s, followed by an interval of at least one minute before the next flash. Wavelengths ranged from 380 to 600 nm in 10 nm increments, presented in random order. Standard test flashes followed each wavelength presentation to assess the dark-adapted state of the eye. If we observed any indications of slight light adaptation, we paused until the test flash response returned to baseline within a tolerance of ± 2 µV, ensuring full recovery to the dark-adapted state. To investigate the possibility of multiple photoreceptor classes or varying expressions of visual pigments, we conducted chromatic adaptation experiments subsequent to the dark-adapted test. For these, we directed an adapting light to the eye via the secondary path of a bifurcated light guide. The source of the adapting light was a white halogen lamp (LS-1, Ocean Optics, Inc., Dunedin, FL, USA), filtered at wavelengths corresponding to the sensitivity peaks previously identified (530 nm, 415 nm, and 380 nm). We focused on detecting changes in the shape of the spectral sensitivity curves or the emergence of new peaks, which would indicate the presence of additional photoreceptor types. We then calculated the inverse of the irradiance required to evoke the criterion response at each wavelength, subsequently normalizing these values to that of the wavelength of maximum sensitivity. We fitted visual pigment templates to these spectral sensitivity data following the method described by Stavenga et al. ( 1993 ). Results All three mantis species showed distinct patterns in their wing reflectance spectra, while they all exhibited minimal UV reflectance. The reflectance curve of H. coronatus was relatively flat, resulting in a white appearance. In the green-colored T. elegans , reflectance was low at shorter wavelengths, increased notably from around 450 nm, and reached a plateau near 550 nm. P. spurca showed lower reflectance compared to the other two species, with a gradual increase from shorter to longer wavelengths, resulting in a brown (also referred to as dark red) appearance. Morphometric measurements also revealed variation in body shape ratios among the three mantis species. T. elegans and H. coronatus , both associated with flower mimicries, had relatively similar morphometric patterns. Their ratios of height-to-width and length-to-width indicate an ellipsoid-shaped body. P. spurca , in contrast, exhibited both relatively higher height-to-width and length-to-width ratios, resulting in a slender and columnar body form. When fully dark-adapted, the ERGs of all three mantis species exhibited a primary sensitivity peak between 515–520 nm and a shoulder at 340–360 nm. With chromatic adaptation, the relative sensitivity of this UV shoulder was enhanced under 530 nm adaptation and diminished under 380 nm adaptation. While all three species appeared to have at least two peaks in their spectral sensitivity curves, T. elegans and P. spurca exhibited tertiary peaks under 530 nm adaptation (442 nm for T. elegans and 413 nm for P. spurca ). In contrast, this 530 nm adaptation did not evoke any tertiary peak in H. coronatus . Discussion The wing reflectance and morphometric measurements strongly suggest that P. spurca is a twig mimicking species and H. coronatus is a flower mimicking species. The elongated body form and reddish-brown coloration of P. spurca closely matches the shape and color of a twig or branch (Juola et al. 2020 ). In contrast, the oval body shape and white coloration of H. coronatus closely resemble the appearance of a white-petaled flower. T. elegans exhibits a green coloration with a spectral reflectance similar to that of green leaves (Virtanen et al. 2020 ), but its body shape is more oval and less flattened compared to classic leaf mimics such as Phyllocrania paradoxa (based on our unpublished data). We frequently observed T. elegans near the base of flowers in the field, supporting the idea that it may mimic green floral structures like sepals. Surprisingly, all three species, particularly the flower-mimicking H. coronatus , exhibited minimal UV reflectance, contrary to expectations given the known UV reflectivity of many flowers (Narbona et al. 2021 ). One possible explanation is that the H. coronatus may mimic flowers that do not reflect UV light (Arnold et al. 2010 ), or it may have lost the UV-reflective structure as adults, as evidenced by the slight UV reflection observed in the wingbuds of H. coronatus (O’Hanlon et al. 2013 ). All three mantis species exhibit a primary spectral sensitivity peak between 515–520 nm, corresponding to the green region of the spectrum. Their maximum sensitivity peak is consistent with the spectral composition of light in forest and woodland environments (de Castro 2000 ), where green wavelengths are most abundant and less absorbed or scattered than other visible wavelengths. This finding is consistent with the sensitivity hypothesis, which suggests that visual pigments of an animal evolve to match the spectral composition of light in its habitat, thereby maximizing sensitivity to the available light (Clarke 1936 ). When fully dark-adapted, the spectral sensitivity curves of all three mantis species showed a shoulder at 340–360 nm. Initially, it was unclear whether this shoulder was due to a UV-sensitive photoreceptor, or merely the sensitivity of the 11-cis-retinal linked to the opsin, which also responds to UV wavelengths (Ross 2013 ). With chromatic adaptation, the relative sensitivity of this UV shoulder is notably enhanced under 530 nm chromatic adaptation and diminished under 380 nm adaptation (Fig. 3 ), suggesting the presence of independent UV sensitivity. The UV sensitivity likely represents an ancestral trait in praying mantises, as it is widespread across insects, including their sister group Blattodea (Mote and Goldsmith 1970 ; Mazokhin-Porshnyakov and Cherkasov 1985 ; Koehler et al. 1987 ; van der Kooi et al. 2021 ). This UV sensitivity could hypothetically help T. elegans approach and H. coronatus avoid flowers more efficiently. Under 530 nm chromatic adaptation, the spectral sensitivity curves of T. elegans and P. spurca exhibited tertiary peaks, indicating the presence of a third photoreceptor type sensitive to blue light. This additional blue sensitivity may enhance visual contrast and, functionally, support more effective background matching align with their mimicry strategies. In contrast, H. coronatus did not show a distinct blue-sensitive peak, consistent with the dichromatic spectral sensitivity observed in all tested Blattodea species (van der Kooi et al. 2021 ). While unlikely, it is possible that H. coronatus possesses blue-sensitive photoreceptors restricted to the ventral region of the eye, which we did not measure; several insect species are known to exhibit regional variation in spectral sensitivity across the compound eye (Martín-Gabarrella et al. 2023 ). Trichromatic vision may allow greater flexibility in visual discrimination for T. elegans and P. spurca , whereas dichromatic vision may be sufficient for H. coronatus , whose ambush predation strategy relies on remaining stationary and visually luring pollinators that mistake it for a flower. Conclusion Our study provides evidence that praying mantises likely possess color vision, with spectral sensitivity curves shaped by the spectral environments in which they live. The presence of multiple sensitivity peaks suggests potential trichromacy in T. elegans and P. spurca , while H. coronatus shows a simpler dichromatic pattern. These visual capabilities may enhance the ability of mantises to select suitable habitats and maintain effective camouflage. By linking spectral sensitivity to ecological context, this research will aid our understanding of the mantis visual system and serve as a reference for future studies. Declarations Funding This research was supported by the National Science Foundation (NSF) under Grant No. IOS-1750833 and the Air Force Office of Scientific Research (AFOSR) through the Multidisciplinary University Research Initiative (MURI) under Award No. FA9550-22-1-0315. Acknowledgments We would like to express our gratitude to Stormie Collins and Dr. Heather Bracken-Grissom for their invaluable support in this study. Their assistance and generosity in providing access to and guidance on the use of the spectrometer in their lab were instrumental in conducting the reflectance measurements. References Arnold SEJ, Faruq S, Savolainen V, et al (2010) FReD: The Floral Reflectance Database — A Web Portal for Analyses of Flower Colour. PLoS ONE 5:e14287. https://doi.org/10.1371/journal.pone.0014287 Autrum H (1948) Über Energie- und Zeitgrenzen der Sinnesempfindungen. 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Vision in deep-sea crustaceans. Journal of Experimental Biology 215:3344–3353. https://doi.org/10.1242/jeb.072033 Juola J, Hovi A, Rautiainen M (2020) Multiangular spectra of tree bark for common boreal tree species in Europe. Silva Fennica 54:. https://doi.org/10.14214/sf.10331 Koehler PG, Agee HR, Leppla NC, Patterson RS (1987) Spectral Sensitivity and Behavioral Response to Light Quality in the German Cockroach (Dictyoptera: Blattellidae). Annals of the Entomological Society of America 80:820–822. https://doi.org/10.1093/aesa/80.6.820 Kral K, Prete FR (2004) In the Mind of a Hunter: The Visual World of the Praying Mantis. In: Complex Worlds from Simpler Nervous Systems. The MIT Press, pp 75–116 Martín-Gabarrella A, Gemeno C, Belušič G (2023) Spectral sensitivity of retinal photoreceptors of tortricid moths is not tuned to diel activity period. 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Journal of Orthoptera Research 22:35–44. https://doi.org/10.1665/034.022.0106 Qian R, Frank TM (2024) Comparative study of spectral sensitivity, irradiance sensitivity, spatial resolution and temporal resolution in the visual systems of Ocypode quadrata and Aratus pisonii. Journal of Experimental Biology 227:. https://doi.org/10.1242/jeb.246813 Ross AC (2013) Vitamin A: Physiology, Dietary Sources, and Requirements. In: Encyclopedia of Human Nutrition. Elsevier, pp 333–339 Sontag C (1971) Spectral Sensitivity Studies on the Visual System of the Praying Mantis, Tenodera sinensis . The Journal of General Physiology 57:93–112. https://doi.org/10.1085/jgp.57.1.93 Stavenga DG, Smits RP, Hoenders BJ (1993) Simple exponential functions describing the absorbance bands of visual pigment spectra. Vision Research 33:1011–1017. https://doi.org/10.1016/0042-6989(93)90237-q van der Kooi CJ, Stavenga DG, Arikawa K, et al (2021) Evolution of Insect Color Vision: From Spectral Sensitivity to Visual Ecology. Annual Review of Entomology 66:435–461. https://doi.org/10.1146/annurev-ento-061720-071644 Virtanen O, Constantinidou E, Tyystjärvi E (2020) Chlorophyll does not reflect green light – how to correct a misconception. Journal of Biological Education 56:552–559. https://doi.org/10.1080/00219266.2020.1858930 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 08 Nov, 2025 Read the published version in Journal of Comparative Physiology A → Version 1 posted Editorial decision: Revision requested 23 Jun, 2025 Reviews received at journal 22 Jun, 2025 Reviews received at journal 16 Jun, 2025 Reviewers agreed at journal 09 Jun, 2025 Reviewers agreed at journal 07 Jun, 2025 Reviewers invited by journal 06 Jun, 2025 Editor assigned by journal 05 Jun, 2025 Submission checks completed at journal 05 Jun, 2025 First submitted to journal 04 Jun, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6816664","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":467948937,"identity":"7052cc0e-2479-433f-869c-85f948ea6301","order_by":0,"name":"Ruchao Qian","email":"","orcid":"","institution":"Florida International University","correspondingAuthor":false,"prefix":"","firstName":"Ruchao","middleName":"","lastName":"Qian","suffix":""},{"id":467948938,"identity":"f81d73da-e946-4fed-98be-ffc9deaf26c9","order_by":1,"name":"Jamie C. Theobald","email":"","orcid":"","institution":"Florida International University","correspondingAuthor":false,"prefix":"","firstName":"Jamie","middleName":"C.","lastName":"Theobald","suffix":""},{"id":467948939,"identity":"d3531d1b-f420-4b4b-853b-736d4a66623a","order_by":2,"name":"Tamara M. Frank","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAu0lEQVRIiWNgGAWjYDAC5gNA4oCEHIxLWAcPWwJIi4UxyVoqEhuI1mLPxvvwc8EZifTt7D2GHxgqrGF68dnCbiw944ZE7s6eM8YSDGfSidAi38YgzfNBInfDjbQECca2w8TYwsb8G6gl3eBGWvIPxn/EaWGT5rkhkWBwI/mYBGMDMVqOsbFZ85yRMNxw5vAxi4Rj6cYEtbC3sTHf5jlWJ29wvLH5xocaa1mCWlBBAmnKR8EoGAWjYBTgAgDIdzmDuY4WvgAAAABJRU5ErkJggg==","orcid":"","institution":"Halmos College of Natural Sciences and Oceanography, Nova Southeastern University","correspondingAuthor":true,"prefix":"","firstName":"Tamara","middleName":"M.","lastName":"Frank","suffix":""}],"badges":[],"createdAt":"2025-06-04 05:53:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6816664/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6816664/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00359-025-01776-z","type":"published","date":"2025-11-08T15:57:56+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":84211981,"identity":"a5809606-cf7d-404f-abbf-be347a217213","added_by":"auto","created_at":"2025-06-09 10:12:03","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":2605066,"visible":true,"origin":"","legend":"\u003cp\u003eRepresentative habitats and wing reflectance of \u003cem\u003eT. elegans\u003c/em\u003e, \u003cem\u003eP. spurca\u003c/em\u003e, and \u003cem\u003eH. coronatus\u003c/em\u003e.\u003cstrong\u003e \u003c/strong\u003eRepresentative images of \u003cem\u003eT. elegans\u003c/em\u003e (\u003cem\u003ea\u003c/em\u003e), \u003cem\u003eP. spurca \u003c/em\u003e(\u003cem\u003eb\u003c/em\u003e)\u003cem\u003e,\u003c/em\u003eand \u003cem\u003eH. coronatus \u003c/em\u003e(\u003cem\u003ec\u003c/em\u003e) placed in environments resembling their natural habitats. Reflectance spectra for adult \u003cem\u003eT. elegans\u003c/em\u003e (\u003cem\u003ed\u003c/em\u003e), \u003cem\u003eP. spurca\u003c/em\u003e (\u003cem\u003ee\u003c/em\u003e), and \u003cem\u003eH. coronatus\u003c/em\u003e (\u003cem\u003ef\u003c/em\u003e) demonstrated the primary color of the dorsal side of their forewings. Gray regions represent standard deviation, and solid lines indicate mean reflectance.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-6816664/v1/2078015a04629b252df8d732.png"},{"id":84211978,"identity":"a473001a-8b92-4d6e-82d1-f8a09719186f","added_by":"auto","created_at":"2025-06-09 10:12:03","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":383453,"visible":true,"origin":"","legend":"\u003cp\u003eBody shape ratios of \u003cem\u003eT. elegans\u003c/em\u003e, \u003cem\u003eP. spurca\u003c/em\u003e, and \u003cem\u003eH. coronatus\u003c/em\u003e based on morphometric measurements.\u003cstrong\u003e \u003c/strong\u003e\u003cem\u003eT. elegans\u003c/em\u003e and \u003cem\u003eH. coronatus\u003c/em\u003eexhibited relatively lower mesothoraco-abdominal length-to-width ratios, while \u003cem\u003eP. spurca\u003c/em\u003e showed higher values in both mesothoraco-abdominal length-to-width and height-to width ratios\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-6816664/v1/1ee0ba087c81de5579a080d9.png"},{"id":84212689,"identity":"b72c9fe2-7314-4255-8367-841ea477a6f8","added_by":"auto","created_at":"2025-06-09 10:20:03","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":897477,"visible":true,"origin":"","legend":"\u003cp\u003eSpectral sensitivity curves for \u003cem\u003eT. elegans\u003c/em\u003e, \u003cem\u003eP. spurca\u003c/em\u003e, and \u003cem\u003eH. coronatus\u003c/em\u003e. Gray and colored lines represent the best-fit absorbance curves under dark and chromatic adaptations. Dark-adapted spectral sensitivity curves for \u003cem\u003eT. elegans \u003c/em\u003e(n=6; \u003cem\u003ea\u003c/em\u003e), \u003cem\u003eP. spurca \u003c/em\u003e(n=5; \u003cem\u003eb\u003c/em\u003e)\u003cem\u003e,\u003c/em\u003e and \u003cem\u003eH. coronatus \u003c/em\u003e(n=4; \u003cem\u003ec\u003c/em\u003e) reveal a primary peak in the green wavelength (515-520 nm). Under 530 nm chromatic adaptation, all three species exhibited a distinctive increase in UV sensitivity, with an additional increase in blue sensitivity observed in T. elegans and P. spurca. Data points represent the inverse of the irradiance required to evoke the criterion response at each wavelength and normalized to the wavelength of maximum sensitivity. Error bars represent SEM.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-6816664/v1/3243de6df69c8113f4085bab.png"},{"id":95564165,"identity":"67d35a81-4a49-4e4d-accb-5fcbf3e5d149","added_by":"auto","created_at":"2025-11-10 16:08:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4548868,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6816664/v1/d51e0253-7236-4e82-bdd2-8094393cb985.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Differential Spectral Adaptation in Praying Mantises","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAmong the order Mantodea, most species have evolved remarkable camouflage, merging exquisitely with specific elements such as flowers, leaves, and branches, to evade predators and ambush prey. But despite functioning in spectrally rich habitats, they have long been thought to be colorblind (Sontag \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e1971\u003c/span\u003e; Fabricant and Herberstein \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; Kral and Prete \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2004\u003c/span\u003e). Previous studies on mantis spectral sensitivity are limited, with only one notable study by Sontag (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e1971\u003c/span\u003e) suggesting that the praying mantis, \u003cem\u003eTenodera sinensis\u003c/em\u003e, might be monochromatic, though findings were not definitive.\u003c/p\u003e \u003cp\u003eHowever, color vision may be important for locating appropriate habitats that minimize detectability. To test this, we used electroretinograms (ERG) to measure the compound eye spectral sensitivities of 3 praying mantis species, representing different mimicry strategies and dwelling habitats (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea-c). \u003cem\u003eTheopropus elegans\u003c/em\u003e, the banded flower mantis (Xishuangbanna population), resides in flowers where body color blends seamlessly with the floral environment, enabling them to feed on pollinators. \u003cem\u003ePopa spurca\u003c/em\u003e, the African twig mantis, inhabits bushes or branches where their twig-like appearance provides camouflage. \u003cem\u003eHymenopus coronatus\u003c/em\u003e, the orchid mantis, also preys on pollinators but lives on green leaves, aggressively mimicking the appearance of a flower. The survival of each relies on inhabiting the correct environment, which would be challenging without color vision.\u003c/p\u003e \u003cp\u003eVisual ecology of a species is often highly specialized to maximize efficiency in natural habitats (Chittka and Briscoe \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2001\u003c/span\u003e; Forward et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e1988\u003c/span\u003e; van der Kooi et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021\u003c/span\u003e), and mantises offer a further opportunity to explore the relationship between their camouflage strategies and visual capabilities, as these strategies are closely tied to their ecological roles and dwelling habitats. However, the camouflage strategies of the three mantis species in this study have not yet been scientifically validated. To address this, we measured wing reflectance spectra and the body morphometric of these mantises to characterize their camouflage objectively. We predicted that all three species would possess more than one visual pigment, with sensitivity peaks corresponding to wavelengths abundant or relevant to their specific habitats. In particular, we expected \u003cem\u003eT. elegans\u003c/em\u003e and \u003cem\u003eH. coronatus\u003c/em\u003e, both associated with flowers, to exhibit heightened sensitivity to ultraviolet (UV) light and reflect UV wavelengths, as many flowers show contrasting UV patterns to attract pollinators (Narbona et al. \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2021\u003c/span\u003e).\u003c/p\u003e"},{"header":"Material and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eAnimal maintenance\u003c/h2\u003e \u003cp\u003eWe bred all animals in captivity under a 12:12-hour light-dark cycle in the laboratory. Each mantis consumed one appropriately sized feeder cockroach every two days. We used only adult females from all three species. To ensure dark adaptation, we kept mantises in complete darkness for three days prior to ERG experiments. The laboratory was maintained at a constant 23\u0026deg;C.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eReflectance measurement\u003c/h3\u003e\n\u003cp\u003eWe used a spectrometer (QE Pro, Ocean Optics) to measure the spectral reflectance of adult female mantis wings over a 350\u0026ndash;650 nm wavelength range. Prior to measurements, we calibrated the spectrometer using polytetrafluoroethylene (PTFE) as a white standard. We positioned a full-spectrum light source (LS-1, Ocean Optics, Inc., Dunedin, FL, USA) at 45\u0026deg; toward the wing, with the spectrometer detecting probe 1 cm away, perpendicular to the wing surface at the point of measurement. Each measurement had an exposure time of 2 seconds, and reflectance curves represented the average normalized values from 3 randomly chosen points on each wing.\u003c/p\u003e\n\u003ch3\u003eMorphometric Measurement\u003c/h3\u003e\n\u003cp\u003eWe performed morphometric measurements to quantify the morphology of the mantis body region primarily covered by the wings. Specifically, we measured three anatomical dimensions: (1) mesothoraco-abdominal length, defined as the distance from the anterior edge of the mesoscutum to the posterior tip of the abdomen, (2) maximum body width, measured as the widest lateral extent of the mesothoraco-abdominal region, and (3) maximum body height, determined as the greatest dorsoventral distance within this region. To minimize variation due to abdominal swelling in gravid individuals, all measurements were performed 6\u0026ndash;10 days after adult emergence, before the significant development of ovaries. We then calculated and plotted body shape ratios of height-to-width and mesothoraco-abdominal length-to-width.\u003c/p\u003e\n\u003ch3\u003eElectrophysiology\u003c/h3\u003e\n\u003cp\u003eWe adopted our electrophysiological recording method from Frank et al. (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2012\u003c/span\u003e), with the equipment apparatus replicated from Qian and Frank (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). ERGs measure the collective electrical response of photoreceptor cells to light (Autrum \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e1948\u003c/span\u003e), which can bypass the pre-retinal filtering effect and provide a direct measurement of spectral sensitivity. Mantises were dark-adapted for at least three days prior to recording, and all animal preparations were conducted under dim red light to avoid unintended visual adaptation.\u003c/p\u003e \u003cp\u003eWe secured animals inside a Faraday cage covered with a light-proof sheet in a dark room. With a micromanipulator and a dissecting microscope (Olympus), we inserted a glass-insulated tungsten microelectrode (Frederick Haer) into the dorsal region of the eye, resting its tip directly above the photoreceptor layer. We placed a silver chloride reference electrode on top of the untested eye to eliminate electrical noise from the body. After placing the electrode, we allowed mantises to dark adapt for 1\u0026ndash;2 hours.\u003c/p\u003e \u003cp\u003eWe delivered stimuli using a 150 W quartz halogen lamp source coupled to a monochromator (CM110, Spectral Products) and guided via a bifurcated light guide cable (EXFO). We positioned the end of the light guide approximately 1 cm from the eye surface, oriented perpendicularly to the insertion site, which illuminated roughly 10% of the eye's visual field. We amplified recording signals with an X Cell-3 Microelectrode Amplifier (FHC, Inc.) with a high impedance probe. We set the amplification level to 2000X and applied filters between 1 and 1000 Hz.\u003c/p\u003e \u003cp\u003eAt the beginning of the recording, we flashed a 490 nm wavelength at an initially dim irradiance of 10\u003csup\u003e8\u003c/sup\u003e photons cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, then gradually increased the irradiance until the flash-elicited response stabilized at 50\u0026micro;V. Measurements began once the response to the adjusted test flash remained constant for one hour.\u003c/p\u003e \u003cp\u003eIn the dark-adapted experiment, we stimulated the eye with monochromatic light flashes, adjusting flash irradiance to elicit a criterion response of 100 \u0026micro;V (or higher if the response was indistinguishable from background noise). Each flash lasted 0.1 s, followed by an interval of at least one minute before the next flash. Wavelengths ranged from 380 to 600 nm in 10 nm increments, presented in random order. Standard test flashes followed each wavelength presentation to assess the dark-adapted state of the eye. If we observed any indications of slight light adaptation, we paused until the test flash response returned to baseline within a tolerance of \u0026plusmn;\u0026thinsp;2 \u0026micro;V, ensuring full recovery to the dark-adapted state.\u003c/p\u003e \u003cp\u003eTo investigate the possibility of multiple photoreceptor classes or varying expressions of visual pigments, we conducted chromatic adaptation experiments subsequent to the dark-adapted test. For these, we directed an adapting light to the eye via the secondary path of a bifurcated light guide. The source of the adapting light was a white halogen lamp (LS-1, Ocean Optics, Inc., Dunedin, FL, USA), filtered at wavelengths corresponding to the sensitivity peaks previously identified (530 nm, 415 nm, and 380 nm). We focused on detecting changes in the shape of the spectral sensitivity curves or the emergence of new peaks, which would indicate the presence of additional photoreceptor types.\u003c/p\u003e \u003cp\u003eWe then calculated the inverse of the irradiance required to evoke the criterion response at each wavelength, subsequently normalizing these values to that of the wavelength of maximum sensitivity. We fitted visual pigment templates to these spectral sensitivity data following the method described by Stavenga et al. (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e1993\u003c/span\u003e).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eAll three mantis species showed distinct patterns in their wing reflectance spectra, while they all exhibited minimal UV reflectance. The reflectance curve of \u003cem\u003eH. coronatus\u003c/em\u003e was relatively flat, resulting in a white appearance. In the green-colored \u003cem\u003eT. elegans\u003c/em\u003e, reflectance was low at shorter wavelengths, increased notably from around 450 nm, and reached a plateau near 550 nm. \u003cem\u003eP. spurca\u003c/em\u003e showed lower reflectance compared to the other two species, with a gradual increase from shorter to longer wavelengths, resulting in a brown (also referred to as dark red) appearance.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eMorphometric measurements also revealed variation in body shape ratios among the three mantis species. \u003cem\u003eT. elegans\u003c/em\u003e and \u003cem\u003eH. coronatus\u003c/em\u003e, both associated with flower mimicries, had relatively similar morphometric patterns. Their ratios of height-to-width and length-to-width indicate an ellipsoid-shaped body. \u003cem\u003eP. spurca\u003c/em\u003e, in contrast, exhibited both relatively higher height-to-width and length-to-width ratios, resulting in a slender and columnar body form.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eWhen fully dark-adapted, the ERGs of all three mantis species exhibited a primary sensitivity peak between 515\u0026ndash;520 nm and a shoulder at 340\u0026ndash;360 nm. With chromatic adaptation, the relative sensitivity of this UV shoulder was enhanced under 530 nm adaptation and diminished under 380 nm adaptation. While all three species appeared to have at least two peaks in their spectral sensitivity curves, \u003cem\u003eT. elegans\u003c/em\u003e and \u003cem\u003eP. spurca\u003c/em\u003e exhibited tertiary peaks under 530 nm adaptation (442 nm for \u003cem\u003eT. elegans\u003c/em\u003e and 413 nm for \u003cem\u003eP. spurca\u003c/em\u003e). In contrast, this 530 nm adaptation did not evoke any tertiary peak in \u003cem\u003eH. coronatus\u003c/em\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe wing reflectance and morphometric measurements strongly suggest that \u003cem\u003eP. spurca\u003c/em\u003e is a twig mimicking species and \u003cem\u003eH. coronatus\u003c/em\u003e is a flower mimicking species. The elongated body form and reddish-brown coloration of \u003cem\u003eP. spurca\u003c/em\u003e closely matches the shape and color of a twig or branch (Juola et al. \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). In contrast, the oval body shape and white coloration of \u003cem\u003eH. coronatus\u003c/em\u003e closely resemble the appearance of a white-petaled flower. \u003cem\u003eT. elegans\u003c/em\u003e exhibits a green coloration with a spectral reflectance similar to that of green leaves (Virtanen et al. \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), but its body shape is more oval and less flattened compared to classic leaf mimics such as \u003cem\u003ePhyllocrania paradoxa\u003c/em\u003e (based on our unpublished data). We frequently observed \u003cem\u003eT. elegans\u003c/em\u003e near the base of flowers in the field, supporting the idea that it may mimic green floral structures like sepals.\u003c/p\u003e \u003cp\u003eSurprisingly, all three species, particularly the flower-mimicking \u003cem\u003eH. coronatus\u003c/em\u003e, exhibited minimal UV reflectance, contrary to expectations given the known UV reflectivity of many flowers (Narbona et al. \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). One possible explanation is that the \u003cem\u003eH. coronatus\u003c/em\u003e may mimic flowers that do not reflect UV light (Arnold et al. \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2010\u003c/span\u003e), or it may have lost the UV-reflective structure as adults, as evidenced by the slight UV reflection observed in the wingbuds of \u003cem\u003eH. coronatus\u003c/em\u003e (O\u0026rsquo;Hanlon et al. \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2013\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eAll three mantis species exhibit a primary spectral sensitivity peak between 515\u0026ndash;520 nm, corresponding to the green region of the spectrum. Their maximum sensitivity peak is consistent with the spectral composition of light in forest and woodland environments (de Castro \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2000\u003c/span\u003e), where green wavelengths are most abundant and less absorbed or scattered than other visible wavelengths. This finding is consistent with the sensitivity hypothesis, which suggests that visual pigments of an animal evolve to match the spectral composition of light in its habitat, thereby maximizing sensitivity to the available light (Clarke \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e1936\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eWhen fully dark-adapted, the spectral sensitivity curves of all three mantis species showed a shoulder at 340\u0026ndash;360 nm. Initially, it was unclear whether this shoulder was due to a UV-sensitive photoreceptor, or merely the sensitivity of the 11-cis-retinal linked to the opsin, which also responds to UV wavelengths (Ross \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). With chromatic adaptation, the relative sensitivity of this UV shoulder is notably enhanced under 530 nm chromatic adaptation and diminished under 380 nm adaptation (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), suggesting the presence of independent UV sensitivity. The UV sensitivity likely represents an ancestral trait in praying mantises, as it is widespread across insects, including their sister group Blattodea (Mote and Goldsmith \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e1970\u003c/span\u003e; Mazokhin-Porshnyakov and Cherkasov \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e1985\u003c/span\u003e; Koehler et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e1987\u003c/span\u003e; van der Kooi et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). This UV sensitivity could hypothetically help \u003cem\u003eT. elegans\u003c/em\u003e approach and \u003cem\u003eH. coronatus\u003c/em\u003e avoid flowers more efficiently.\u003c/p\u003e \u003cp\u003eUnder 530 nm chromatic adaptation, the spectral sensitivity curves of \u003cem\u003eT. elegans\u003c/em\u003e and \u003cem\u003eP. spurca\u003c/em\u003e exhibited tertiary peaks, indicating the presence of a third photoreceptor type sensitive to blue light. This additional blue sensitivity may enhance visual contrast and, functionally, support more effective background matching align with their mimicry strategies. In contrast, \u003cem\u003eH. coronatus\u003c/em\u003e did not show a distinct blue-sensitive peak, consistent with the dichromatic spectral sensitivity observed in all tested Blattodea species (van der Kooi et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). While unlikely, it is possible that \u003cem\u003eH. coronatus\u003c/em\u003e possesses blue-sensitive photoreceptors restricted to the ventral region of the eye, which we did not measure; several insect species are known to exhibit regional variation in spectral sensitivity across the compound eye (Mart\u0026iacute;n-Gabarrella et al. \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Trichromatic vision may allow greater flexibility in visual discrimination for \u003cem\u003eT. elegans\u003c/em\u003e and \u003cem\u003eP. spurca\u003c/em\u003e, whereas dichromatic vision may be sufficient for \u003cem\u003eH. coronatus\u003c/em\u003e, whose ambush predation strategy relies on remaining stationary and visually luring pollinators that mistake it for a flower.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eOur study provides evidence that praying mantises likely possess color vision, with spectral sensitivity curves shaped by the spectral environments in which they live. The presence of multiple sensitivity peaks suggests potential trichromacy in \u003cem\u003eT. elegans\u003c/em\u003e and \u003cem\u003eP. spurca\u003c/em\u003e, while \u003cem\u003eH. coronatus\u003c/em\u003e shows a simpler dichromatic pattern. These visual capabilities may enhance the ability of mantises to select suitable habitats and maintain effective camouflage. By linking spectral sensitivity to ecological context, this research will aid our understanding of the mantis visual system and serve as a reference for future studies.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was supported by the National Science Foundation (NSF) under Grant No. IOS-1750833 and the Air Force Office of Scientific Research (AFOSR) through the Multidisciplinary University Research Initiative (MURI) under Award No. FA9550-22-1-0315.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe would like to express our gratitude to Stormie Collins and Dr. Heather Bracken-Grissom for their invaluable support in this study. Their assistance and generosity in providing access to and guidance on the use of the spectrometer in their lab were instrumental in conducting the reflectance measurements.\u003c/p\u003e\n"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eArnold SEJ, Faruq S, Savolainen V, et al (2010) FReD: The Floral Reflectance Database \u0026mdash; A Web Portal for Analyses of Flower Colour. PLoS ONE 5:e14287. https://doi.org/10.1371/journal.pone.0014287\u003c/li\u003e\n\u003cli\u003eAutrum H (1948) \u0026Uuml;ber Energie- und Zeitgrenzen der Sinnesempfindungen. Die Naturwissenschaften 35:361\u0026ndash;369. https://doi.org/10.1007/bf00594907\u003c/li\u003e\n\u003cli\u003eChittka L, Briscoe A (2001) Why Sensory Ecology Needs to Become More Evolutionary \u0026mdash; Insect Color Vision as a Case in Point. In: Ecology of Sensing. Springer Berlin Heidelberg, Berlin, Heidelberg, pp 19\u0026ndash;37\u003c/li\u003e\n\u003cli\u003eClarke GL (1936) On the Depth at Which Fish Can See. Ecology 17:452\u0026ndash;456. https://doi.org/10.2307/1931845\u003c/li\u003e\n\u003cli\u003ede Castro F (2000) Light spectral composition in a tropical forest: measurements and model. Tree Physiology 20:49\u0026ndash;56. https://doi.org/10.1093/treephys/20.1.49\u003c/li\u003e\n\u003cli\u003eFabricant SA, Herberstein ME (2014) Hidden in plain orange: aposematic coloration is cryptic to a colorblind insect predator. Behavioral Ecology 26:38\u0026ndash;44. https://doi.org/10.1093/beheco/aru157\u003c/li\u003e\n\u003cli\u003eForward RB Jr, Cronin TW, Douglass JK (1988) The visual pigments of crabs. Journal of Comparative Physiology A 162:479\u0026ndash;490. https://doi.org/10.1007/bf00612513\u003c/li\u003e\n\u003cli\u003eFrank TM, Johnsen S, Cronin TW (2012) Light and vision in the deep-sea benthos: II. Vision in deep-sea crustaceans. 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The MIT Press, pp 75\u0026ndash;116\u003c/li\u003e\n\u003cli\u003eMart\u0026iacute;n-Gabarrella A, Gemeno C, Belu\u0026scaron;ič G (2023) Spectral sensitivity of retinal photoreceptors of tortricid moths is not tuned to diel activity period. Journal of Experimental Biology 226:. https://doi.org/10.1242/jeb.245461\u003c/li\u003e\n\u003cli\u003eMazokhin-Porshnyakov GA, Cherkasov AD (1985) Spectral sensitivity of visual cells of the compound eye ofBlatta orientalis. Neurophysiology 17:48\u0026ndash;51. https://doi.org/10.1007/bf01052791\u003c/li\u003e\n\u003cli\u003eMote MI, Goldsmith TH (1970) Spectral sensitivities of color receptors in the compound eye of the cockroach Periplaneta. Journal of Experimental Zoology 173:137\u0026ndash;145. https://doi.org/10.1002/jez.1401730203\u003c/li\u003e\n\u003cli\u003eNarbona E, del Valle JC, Whittall JB (2021) Painting the green canvas: how pigments produce flower colours. The Biochemist 43:6\u0026ndash;12. https://doi.org/10.1042/bio_2021_137\u003c/li\u003e\n\u003cli\u003eO\u0026rsquo;hanlon JC, Li D, Norma-Rashid Y (2013) Coloration and Morphology of the Orchid MantisHymenopus coronatus(Mantodea: Hymenopodidae). Journal of Orthoptera Research 22:35\u0026ndash;44. https://doi.org/10.1665/034.022.0106\u003c/li\u003e\n\u003cli\u003eQian R, Frank TM (2024) Comparative study of spectral sensitivity, irradiance sensitivity, spatial resolution and temporal resolution in the visual systems of Ocypode quadrata and Aratus pisonii. Journal of Experimental Biology 227:. https://doi.org/10.1242/jeb.246813\u003c/li\u003e\n\u003cli\u003eRoss AC (2013) Vitamin A: Physiology, Dietary Sources, and Requirements. In: Encyclopedia of Human Nutrition. Elsevier, pp 333\u0026ndash;339\u003c/li\u003e\n\u003cli\u003eSontag C (1971) Spectral Sensitivity Studies on the Visual System of the Praying Mantis, Tenodera sinensis . The Journal of General Physiology 57:93\u0026ndash;112. https://doi.org/10.1085/jgp.57.1.93\u003c/li\u003e\n\u003cli\u003eStavenga DG, Smits RP, Hoenders BJ (1993) Simple exponential functions describing the absorbance bands of visual pigment spectra. Vision Research 33:1011\u0026ndash;1017. https://doi.org/10.1016/0042-6989(93)90237-q\u003c/li\u003e\n\u003cli\u003evan der Kooi CJ, Stavenga DG, Arikawa K, et al (2021) Evolution of Insect Color Vision: From Spectral Sensitivity to Visual Ecology. Annual Review of Entomology 66:435\u0026ndash;461. https://doi.org/10.1146/annurev-ento-061720-071644\u003c/li\u003e\n\u003cli\u003eVirtanen O, Constantinidou E, Tyystj\u0026auml;rvi E (2020) Chlorophyll does not reflect green light \u0026ndash; how to correct a misconception. Journal of Biological Education 56:552\u0026ndash;559. https://doi.org/10.1080/00219266.2020.1858930\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-comparative-physiology-a","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jcpa","sideBox":"Learn more about [Journal of Comparative Physiology A](http://link.springer.com/journal/359)","snPcode":"359","submissionUrl":"https://submission.nature.com/new-submission/359/3","title":"Journal of Comparative Physiology A","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6816664/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6816664/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003ePraying mantises often display elaborate camouflage, disappearing into the shapes, textures, and colors around them. But they have largely been thought to be monochromats, unable to perceive the colors they mimic. To examine this, we tested the compound eye spectral sensitivity of three species of praying mantises, each representing unique mimicry strategies: \u003cem\u003eTheopropus elegans\u003c/em\u003e, \u003cem\u003ePopa spurca\u003c/em\u003e, and \u003cem\u003eHymenopus coronatus\u003c/em\u003e. We quantified mantis sensitivity to light, ranging from 350 to 650 nm wavelength, using electroretinograms under both dark and chromatic adaptation. We find distinct sensitivity peaks that suggest the presence of multiple photoreceptor types or varying expressions of visual pigments across the species studied. \u003cem\u003eT. elegans\u003c/em\u003e and \u003cem\u003eP. spurca\u003c/em\u003e exhibited potential trichromatic vision, with primary sensitivity peaks in green (515\u0026ndash;520 nm), and secondary and tertiary peaks in ultraviolet (340\u0026ndash;360 nm) and blue (442 nm and 413 nm). Conversely, \u003cem\u003eH. coronatus\u003c/em\u003e displayed a simpler dichromatic pattern. This suggests praying mantises have the capacity for color vision, likely adapted to enhance camouflage and predatory efficiency in their environments.\u003c/p\u003e","manuscriptTitle":"Differential Spectral Adaptation in Praying Mantises","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-09 10:11:58","doi":"10.21203/rs.3.rs-6816664/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-06-23T05:06:27+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-22T23:25:00+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-16T12:11:49+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"269869452401461522575100532752155281467","date":"2025-06-09T22:14:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"225070057874173812107595009594899133393","date":"2025-06-07T14:32:36+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-06-06T09:42:53+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-06-05T14:24:42+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-06-05T14:22:32+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Comparative Physiology A","date":"2025-06-04T05:41:25+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-comparative-physiology-a","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jcpa","sideBox":"Learn more about [Journal of Comparative Physiology A](http://link.springer.com/journal/359)","snPcode":"359","submissionUrl":"https://submission.nature.com/new-submission/359/3","title":"Journal of Comparative Physiology A","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"59029f12-1617-4eb0-a5bf-09c8b1b01edf","owner":[],"postedDate":"June 9th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-11-10T16:05:22+00:00","versionOfRecord":{"articleIdentity":"rs-6816664","link":"https://doi.org/10.1007/s00359-025-01776-z","journal":{"identity":"journal-of-comparative-physiology-a","isVorOnly":false,"title":"Journal of Comparative Physiology A"},"publishedOn":"2025-11-08 15:57:56","publishedOnDateReadable":"November 8th, 2025"},"versionCreatedAt":"2025-06-09 10:11:58","video":"","vorDoi":"10.1007/s00359-025-01776-z","vorDoiUrl":"https://doi.org/10.1007/s00359-025-01776-z","workflowStages":[]},"version":"v1","identity":"rs-6816664","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6816664","identity":"rs-6816664","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}