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Kivelä L, Elgert C, Lehtonen TK, Candolin U. The color of artificial light affects mate attraction in the common glow-worm. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159451. [PMID: 36252663 DOI: 10.1016/j.scitotenv.2022.159451] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 09/22/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
Artificial light at night, often referred to as 'light pollution', is a global environmental problem that threatens many nocturnal organisms. One such species is the European common glow-worm (Lampyris noctiluca), in which reproduction relies on the ability of sedentary bioluminescent females to attract flying males to mate. Previous studies show that broad-spectrum white artificial light interferes with mate attraction in this beetle. However, much less is known about wavelength-specific effects. In this study, we experimentally investigate how the peak wavelength (color) of artificial light affects glow-worm mate attraction success in the field by using dummy females that trap males landing to mate. Each dummy was illuminated from above by either a blue (peak wavelength: 452 nm), white (449 nm), yellow (575 nm), or red (625 nm) LED lighting, or light switched off in the control. We estimated mate attraction success as both the probability of attracting at least one male and the number of males attracted. In both cases, mate attraction success depended on the peak wavelength of the artificial light, with short wavelengths (blue and white) decreasing it more than long wavelengths (yellow and red). Hence, adjusting the spectrum of artificial light can be an effective measure for mitigating the negative effects of light pollution on glow-worm reproduction.
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Affiliation(s)
- Linnea Kivelä
- Organismal and Evolutionary Biology, University of Helsinki, PO Box 65, 00014 Helsinki, Finland; Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland.
| | - Christina Elgert
- Organismal and Evolutionary Biology, University of Helsinki, PO Box 65, 00014 Helsinki, Finland; Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland
| | - Topi K Lehtonen
- Organismal and Evolutionary Biology, University of Helsinki, PO Box 65, 00014 Helsinki, Finland; Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland; Natural Resources Institute, Paavo Havaksen tie 3, 90570 Oulu, Finland
| | - Ulrika Candolin
- Organismal and Evolutionary Biology, University of Helsinki, PO Box 65, 00014 Helsinki, Finland; Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland
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Hopkins J, Kaitala V, Kaitala A. Beauty is in the eye of the beholder: mate choice in glow‐worms depends on perceived, not emitted signals. OIKOS 2022. [DOI: 10.1111/oik.09468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Juhani Hopkins
- Ecology and Genetics Research Group, Univ. of Oulu Oulu Finland
- Tvärminne Zoological Station, Univ. of Helsinki Helsinki Finland
| | - Veijo Kaitala
- Organismal and Evolutionary Biology Research Programme, Univ. of Helsinki Helsinki Finland
| | - Arja Kaitala
- Ecology and Genetics Research Group, Univ. of Oulu Oulu Finland
- Tvärminne Zoological Station, Univ. of Helsinki Helsinki Finland
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Elgert C, Lehtonen TK, Kaitala A, Candolin U. Sexual selection for bright females prevails under light pollution. Curr Zool 2021; 67:329-331. [PMID: 34616925 PMCID: PMC8489004 DOI: 10.1093/cz/zoaa071] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 10/22/2020] [Indexed: 11/25/2022] Open
Affiliation(s)
- Christina Elgert
- Organismal and Evolutionary Biology, University of Helsinki, Helsinki, PO Box 65, 00014, Finland.,Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, Hanko, 10900, Finland
| | - Topi K Lehtonen
- Organismal and Evolutionary Biology, University of Helsinki, Helsinki, PO Box 65, 00014, Finland.,Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, Hanko, 10900, Finland.,Department of Ecology and Genetics, University of Oulu, Oulu, PO Box 3000, 00014, Finland, 90014
| | - Arja Kaitala
- Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, Hanko, 10900, Finland.,Department of Ecology and Genetics, University of Oulu, Oulu, PO Box 3000, 00014, Finland, 90014
| | - Ulrika Candolin
- Organismal and Evolutionary Biology, University of Helsinki, Helsinki, PO Box 65, 00014, Finland.,Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, Hanko, 10900, Finland
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Hopkins J, Lehtonen TK, Baudry G, Kaitala A. Costly mating delays drive female ornamentation in a capital breeder. Ecol Evol 2021. [DOI: 10.1002/ece3.7719] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Juhani Hopkins
- Ecology and Genetics Research Unit University of Oulu Oulu Finland
- Tvärminne Zoological Station University of Helsinki Hanko Finland
| | - Topi K. Lehtonen
- Ecology and Genetics Research Unit University of Oulu Oulu Finland
- Tvärminne Zoological Station University of Helsinki Hanko Finland
| | - Gautier Baudry
- Ecology and Genetics Research Unit University of Oulu Oulu Finland
- Tvärminne Zoological Station University of Helsinki Hanko Finland
| | - Arja Kaitala
- Ecology and Genetics Research Unit University of Oulu Oulu Finland
- Tvärminne Zoological Station University of Helsinki Hanko Finland
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Lehtonen TK, Babic NL, Piepponen T, Valkeeniemi O, Borshagovski AM, Kaitala A. High road mortality during female-biased larval dispersal in an iconic beetle. Behav Ecol Sociobiol 2021; 75:26. [PMID: 33487857 PMCID: PMC7811152 DOI: 10.1007/s00265-020-02962-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 12/10/2020] [Accepted: 12/28/2020] [Indexed: 01/31/2023]
Abstract
ABSTRACT Animals often disperse from one habitat to another to access mates or suitable breeding sites. The costs and benefits of such movements depend, in part, on the dispersing individuals' phenotypes, including their sex and age. Here we investigated dispersal and road-related mortality in larvae of a bioluminescent beetle, the European common glow-worm, Lampyris noctiluca, in relation to habitat, sex and proximity of pupation. We expected these variables to be relevant to larval dispersal because adult females are wingless, whereas adult males fly when searching for glowing females. We found that dispersing glow-worm larvae were almost exclusively females and close to pupation. The larvae were often found on a road, where they were able to move at relatively high speeds, with a tendency to uphill orientation. However, each passing vehicle caused a high mortality risk, and we found large numbers of larvae run over by cars, especially close to covered, forest-like habitat patches. In contrast, adult females in the same area were most often found glowing in more open rocky and grassy habitats. These findings demonstrate an underappreciated ecological strategy, sex-biased dispersal at larval phase, motivated by different habitat needs of larvae and wingless adult females. The results are also consistent with roads being an ecological trap, facilitating dispersal and presumably females' signal visibility but causing severe larval mortality just before the reproductive stage. Hence, in addition to the previously recognised threats of urbanisation, even low traffic volumes have a high potential to negatively affect especially females of this iconic beetle. SIGNIFICANCE STATEMENT Animals sometimes need to move from one habitat to another to find mating partners or breeding sites. We found this need to result in strongly female-biased larval dispersal in the European common glow-worm, a beetle known for the glow of wingless females that attract flying males to mate. Female larvae moving between habitats often used a road or trail but perished in high numbers when run over by cars. Hence, roads are likely to be ecological traps for the female glow-worm larvae, attracting them during dispersal, but causing grave mortality. The sex-biased larval dispersal, demonstrated in this study, is a poorly known ecological strategy that was found to be very risky in a human-modified landscape. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s00265-020-02962-6.
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Affiliation(s)
- Topi K. Lehtonen
- Department of Ecology and Genetics, University of Oulu, Post Box 3000, 90014 Oulu, Finland ,Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland ,Organismal and Evolutionary Biology, University of Helsinki, PO Box 65, 00014 Helsinki, Finland
| | - Natarsha L. Babic
- Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland ,School of Biological Sciences, Monash University, Clayton Campus, Melbourne, Victoria 3800 Australia
| | - Timo Piepponen
- Department of Ecology and Genetics, University of Oulu, Post Box 3000, 90014 Oulu, Finland ,Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland
| | - Otso Valkeeniemi
- Department of Ecology and Genetics, University of Oulu, Post Box 3000, 90014 Oulu, Finland ,Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland
| | - Anna-Maria Borshagovski
- Department of Ecology and Genetics, University of Oulu, Post Box 3000, 90014 Oulu, Finland ,Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland
| | - Arja Kaitala
- Department of Ecology and Genetics, University of Oulu, Post Box 3000, 90014 Oulu, Finland ,Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, 10900 Hanko, Finland
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Borshagovski AM, Saari P, Lehtonen TK, Kaitala A. When night never falls: female sexual signalling in a nocturnal insect along a latitudinal gradient. Behav Ecol Sociobiol 2020. [DOI: 10.1007/s00265-020-02927-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
AbstractThe environment can play an important role in animal communication by affecting signal transmission and detection. Variation in the signalling environment is expected to be especially pronounced in widely distributed species, potentially affecting how their signals are detected. Such environmental variability is presumably relevant for sedentary females of a nocturnal capital breeder, the European common glow-worm (Lampyris noctiluca), which produce green light during the night to attract flying males to mate. Being widely distributed in Europe, glow-worm populations are exposed to both rapidly descending, darker summer nights in the south, and slowly dimming, brighter summer nights further north, with the latter potentially posing challenges to the visibility of the female glow. To test how female signalling is affected by latitude, we sampled glowing females during summer nights along a latitudinal gradient in Finland, Northern Europe, and used a novel apparatus to measure the intensity and peak wavelength (hue/colour) of their glow. Surprisingly, females at higher latitudes, similar to those at lower latitudes, were commonly glowing during the brightest (and hence the shortest) nights of the year. Females also glowed brighter in more northern areas, partly due to their larger body size, whereas the colour of their glow was not associated with latitude. Since females glow even during midsummer, independent of latitude, the increase in glow intensity at higher latitudes presumably serves to maintain signal visibility in brighter signalling conditions. Overall, these findings highlight the influence of environmental conditions on the evolution of sexual signals, especially in the context of species distribution range.Significance statementWhen environmental conditions impact signal transmission and perception, local conditions can have a crucial role in shaping animal communication and signal evolution. To analyse how dark-dependant common glow-worm females cope with variable nocturnal light environments, we used a novel apparatus, presumably not applied to living animals before, to measure female glow intensity at various latitudes along a latitudinal gradient. Interestingly, females did not avoid signalling during the brightest summer nights, but instead, their glow intensity and body size both increased with latitude. These findings suggest that females can ensure visibility to mate-searching males over a range of local conditions. Our study therefore shows how females can adapt to environmental constraints on signal visibility, and how the expression of sexual signals is shaped not only by social interactions but also by the signalling environment.
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Lehtonen TK, Kaitala A. Leave me alone: solitary females attract more mates in a nocturnal insect. Behav Ecol 2020. [DOI: 10.1093/beheco/araa049] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Spatial distributions of sexual competitors and potential mating partners have a large impact on sexual selection and mating systems. Typically, such effects are investigated with regard to male aggregations. However, females may also need to compete for mating opportunities. Here, we investigated the consequences of clustering and rival attractiveness on female mate attraction success under field conditions in a nocturnal beetle, the common glowworm, Lampyrus noctiluca. We placed dummy females of two glow intensity (attractiveness) levels either alone or in clusters of varying attractiveness compositions. We found that, by displaying alone rather than in a cluster, females have a higher probability of mating and greater potential to exercise mate choice. Within clusters, females of both attractiveness levels had the highest probability of mating when having neighbors of only the less attractive type. These results show that both the presence and attractiveness of rivals can strongly influence females’ mate attraction. The findings also suggest that the typical distribution of glowing females in the wild is better explained by female than male benefits. Hence, the results highlight the important links between spatial distribution of females, male mate searching, and sexual selection.
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Affiliation(s)
- Topi K Lehtonen
- Department of Ecology and Genetics, University of Oulu, Oulu, Finland
- Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, Hanko, Finland
| | - Arja Kaitala
- Department of Ecology and Genetics, University of Oulu, Oulu, Finland
- Tvärminne Zoological Station, University of Helsinki, J.A. Palménin tie 260, Hanko, Finland
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