Abstract
Sensory traps occur when a signal evolves to mimic a cue to which the receiver responds favorably in another context. For example, if females are attracted to the noise a prey item makes, then a conspecific male can mimic that noise, thereby attracting females in the context of mating. Thus, sensory traps can be beneficial to receivers since attraction helps locating males more efficiently. But what happens when receivers are less attracted by the sensory trap outside of the original context (due to the cost of the response for instance)? Does this weaken and eventually “break” the sensory trap? Here, we show that a rare, small mud structure (a semidome) built by some male fiddler crabs (Austruca mjoebergi) at their burrow entrances are most likely relics of the sensory traps used by other fiddler crabs (the larger, far more abundant hoods of Leptuca species). Females of A. mjoebergi have retained their tendency to move towards vertical structures for protection when threatened by a predator—the original context thought to be important in the evolution of sensory traps in other fiddler crab species. However, females show no significant preference for males with semidomes. Additionally, males do not use the semidomes as landmarks to relocate their burrows when courting. The results suggest that in A. mjoebergi, semidomes do not function as sensory traps, despite the existence of a pre-existing bias in females. We suggest that semidomes have lost their attractiveness in the mating context due to ecological features, such as predation and environmental heterogeneity.
Significance statement
There is growing evidence of sensory traps in many animal species, with an ever-widening range of contexts from nuptial gift giving in spiders to egg recognition in non-brood-parasitized birds. While we are starting to understand the significance of sensory traps, little thought has been given to what happens when they break down. If there is a change in the original context that favored the receiver’s response, then there is likely to be a subsequent change in the receiver’s bias and finally, in the sensory trap. If the mimic of the original stimulus does not induce a beneficial response in the receiver anymore, the sensory trap would become inefficient and stop being selected. The effect will be most profound when the sensory trap was costly to set up, since there will be selection against its retention. Here, we show that a sensory trap can become a relic when ecological conditions change and make it not functional anymore. To our knowledge, it is the first study providing such empirical evidence.
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References
Blumstein DT, Daniel JC, Griffin AS, Evans CS (2000) Insular tammar wallabies (Macropus eugenii) respond to visual but not acoustic cues from predators. Behav Ecol 11:528–535
Booksmythe I, Detto T, Backwell PRY (2008) Female fiddler crabs settle for less: the travel costs of mate choice. Anim Behav 76:1775–1781. https://doi.org/10.1016/j.anbehav.2008.07.022
Byers JA (1998) American pronghorn: social adaptations and the ghosts of predators past. University Chicago Press, Chicago
Cannicci S, Fratini S, Vannini M (1999) Short-range homing in fiddler crabs (Ocypodidae, genus Uca): a homing mechanism not based on local visual landmarks. Ethology 105:867–880. https://doi.org/10.1046/j.1439-0310.1999.00453.x
Chatterjee S, Das TK, Chakraborty SK (2014) Reproductive biology and bioturbatory activities of two sympatric species of fiddler crabs Uca lactea annulipes and Uca triangularis bengali (Decopada: Ocypodidae) at the East Midnapore Coastal Belt of West Bengal, India. J Biol Life Sci 5:106–127. https://doi.org/10.5296/jbls.v5i2.5809
Christy JH (1988) Pillar function in the fiddler crab Uca beebei (II): competitive courtship signaling. Ethology 78:113–128. https://doi.org/10.1111/j.1439-0310.1988.tb00223.x
Christy JH (1995) Mimicry, mate choice, and the sensory trap hypothesis. Am Nat 146:171–181. https://doi.org/10.1086/285793
Christy JH, Backwell PRY, Goshima S, Kreuter T (2002) Sexual selection for structure building by courting male fiddler crabs: an experimental study of behavioral mechanisms. Behav Ecol 13:366–374. https://doi.org/10.1093/beheco/13.3.366
Christy JH, Backwell PRY, Schober U (2003a) Interspecific attractiveness of structures built by courting male fiddler crabs: experimental evidence of a sensory trap. Behav Ecol Sociobiol 53:84–91. https://doi.org/10.1007/s00265-002-0553-4
Christy JH, Baum JK, Backwell PRY (2003b) Attractiveness of sand hoods built by courting male fiddler crabs, Uca musica: test of a sensory trap hypothesis. Anim Behav 66:89–94. https://doi.org/10.1006/anbe.2003.2196
Crane J (1975) Fiddler crabs of the world. Princeton University Press, Princeton
Detto T (2007) The fiddler crab Uca mjoebergi uses colour vision in mate choice. Proc R Soc B Biol Sci 274:2785–2790. https://doi.org/10.1098/rspb.2007.1059
Detto T, Backwell PRY (2009) The fiddler crab Uca mjoebergi uses ultraviolet cues in mate choice but not aggressive interactions. Anim Behav 78:407–411. https://doi.org/10.1016/j.anbehav.2009.05.014
Endler JA, Basolo AL (1998) Sensory ecology, receiver biases and sexual selection. Trends Ecol Evol 13:415–420
Holman L, Kahn AT, Backwell PRY (2014) Fiddlers on the roof: elevation muddles mate choice in fiddler crabs. Behav Ecol 25:271–275. https://doi.org/10.1093/beheco/art125
Kahn AT, Dolstra T, Jennions MD, Backwell PRY (2013) Strategic male courtship effort varies in concert with adaptive shifts in female mating preferences. Behav Ecol 24:906–913. https://doi.org/10.1093/beheco/art017
Kim TW, Christy JH, Choe JC (2004) Semidome building as sexual signaling in the fiddler crab Uca Lactea (Brachyura: Ocypodidae). Journ Crust Biol 24:673–679
Kim TW, Christy JH, Choe JC (2007) A preference for a sexual signal keeps females safe. PLoS One 2:e422. https://doi.org/10.1371/journal.pone.0000422
Kim TW, Christy JH, Dennenmoser S, Choe JC (2009) The strength of a female mate preference increases with predation risk. Proc R Soc Biol Sci 276:775–780. https://doi.org/10.1098/rspb.2008.1070
Koga T, Backwell PRY, Christy JH, Murai M, Kasuya E (2001) Male-biased predation of a fiddler crab. Anim Behav 62:201–220. https://doi.org/10.1006/anbe.2001.1740
Koga T, Backwell PRY, Jennions MD, Christy JH (1998) Elevated predation risk changes mating behaviour and courtship in a fiddler crab. Proc R Soc B Biol Sci 265:1385–1390. https://doi.org/10.1098/rspb.1998.0446
Masunari S (2012) Hood construction as an indication of the breeding period of the fiddler crab Uca (Leptuca) leptodactyla Rathbun, 1898 (Decapoda, Ocypodidae) from Guaratuba Bay, southern Brazil. Crustaceana 85:1153–1169. https://doi.org/10.1163/156854012X651277
Matsumasa M, Minoru M, Christy JH (2013) A low-cost sexual ornament reliably signals male condition in the fiddler crab Uca beebei. Anim Behav 85:1335–1341. https://doi.org/10.1016/j.anbehav.2013.03.024
Mokhlesi A, Kamrani E, Backwell P, Sajjadi M (2011) Study on the behaviour of two fiddler crabs, Uca sindensis and Uca annulipes (Decapoda: Ocypodidae), in Bandar Abbas, Iran. J Mar Biol Assoc United Kingdom 91:245–249. https://doi.org/10.1017/S0025315410000172
Muramatsu D (2009) To build or not to build – or to destroy burrow hoods in a population of Uca Lactea. Journ Crust Biol 29:290–292. https://doi.org/10.1651/08-3122.1
Peso M, Curran E, Backwell PRY (2016) Not what it looks like: mate-searching behaviour, mate preferences and clutch production in wandering and territory-holding female fiddler crabs. R Soc Open Sci 3:160339. https://doi.org/10.1098/rsos.160339
Peso M, Telford L, Backwell PRY (2014) Comparison shopping: detectability and mate preferences in a fiddler crab. Anim Behav 88:107–111. https://doi.org/10.1016/j.anbehav.2013.11.021
Proctor HC (1991) Courtship in the water mite Neumania papillator: males capitalize on female adaptations for predation. Anim Behav 42:589–598. https://doi.org/10.1016/S0003-3472(05)80242-8
Reaney LT, Sims RA, Sims SWM et al (2008) Experiments with robots explain synchronized courtship in fiddler crabs. Curr Biol 18:62–63
Ribeiro PD, Christy JH, Rissanen RJ, Kim TW (2006) Males are attracted by their own courtship signals. Behav Ecol Sociobiol 61:81–89. https://doi.org/10.1007/s00265-006-0238-5
Rothstein SI (2001) Relic behaviours, coevolution and the retention versus loss of host defences after episodes of avian brood parasitism. Anim Behav 61:95–107. https://doi.org/10.1006/anbe.2000.1570
Ryan MJ (1990) Sexual selection, sensory system and sensory exploitation. Oxf Surv Evol Biol 7:157–195
Saher NU, Qureshi NA (2017) Construction of earthen structure as a sexual signals in the fiddler crabs. Int J Aquat Biol 5:40–46
Shih H-T, Ng PKL, Davie PJF, Schubart CD, Türkay M, Naderloo R, Jones D, Liu M-Y (2016) Systematics of the family Ocypodidae Rafinesque, 1815 (Crustacea: Brachyura), based on phylogenetic relationships, with a reorganization of subfamily rankings and a review of the taxonomic status of Uca Leach, 1814, Sensu lato and its subgenera. Raffles Bull Zool 64:139–175
Yamaguchi T, Tabata S, Henmi Y (2005) Hood building and territory usage in the fiddler crab, Uca lactea (De Haan, 1835). Crustaceana 78:1117–1141. https://doi.org/10.1163/156854005775361007
Zeil J, Hemmi JM (2006) The visual ecology of fiddler crabs. J Comp Physiol A 192:1–25. https://doi.org/10.1007/s00359-005-0048-7
Acknowledgements
We thank Craig Clark for invaluable help with the fieldwork and Michael Jennions for commenting on the manuscript. We also thank our two anonymous reviewers for having helped us improving the manuscript with their in-depth reading and relevant comments.
Funding
The study was funded by an Australian Research Council Discovery grant to PRYB (DP160100316) and a Research School of Biology (Australian National University) grant to PRYB (R41060 52PB).
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This research was approved by the Australian National University Animal Ethics Committee (permit A2015/54). We followed all required guidelines. We limited the handling and the amount of time each crab was used as much as possible. No crab was injured during the research, and they all continued their regular activities after release. The work was conducted under a research permit from the Darwin City Council (permit no. 3648724).
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Communicated by T. Breithaupt
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Bourdiol, J., Chou, CC., Perez, D.M. et al. Investigating the role of a mud structure in a fiddler crab: do semidomes have a reproductive function?. Behav Ecol Sociobiol 72, 141 (2018). https://doi.org/10.1007/s00265-018-2556-9
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DOI: https://doi.org/10.1007/s00265-018-2556-9