Abstract
The quality of many animal signals varies, perhaps through their use in different contexts or by representing an adaptive response to reduce the risk of exploitation. Spiders of the orb weaver genus Argiope add linear, cruciate or circular silk structures to their orb webs, creating inter- and intra-specific polymorphic visual signals. Different decoration patterns are frequently attributed to different signal effects, but this view is contradicted by commonly observed intraspecific variation in decorating behaviour. Adults of Argiope mascordi are bimodal web decorators, building two distinct patterns, circular and cruciate silk structures. We investigated the variation of patterns under controlled, invariant laboratory conditions. Circular decorations were most frequent, but individuals often switch to the other pattern. This variation neither increased nor decreased over time, suggesting that pattern variability is primarily intrinsic rather than an exclusive response to environmental changes. Accordingly, we discuss the evolutionary implications in the light of the conservation of a single signal function through maintaining the variation of its quality and the alternative view that silk decorations may not represent adaptive signals at all.
References
Arias M, Mappes J, Théry M, Llaurens V (2016) Inter-species variation in unpalatability does not explain polymorphism in a mimetic species. Evol Ecol 30:419–433
Blackledge TA, Wenzel JW (2001) Silk mediated defense by an orb web spider against predatory mud-dauber wasps. Behaviour 138:155–171
Bruce MJ (2006) Silk decorations: controversy and consensus. J Zool 269:89–97
Bruce MJ, Herberstein ME (2005) Web decoration polymorphism in Argiope Audouin, 1826 (Araneidae) spiders: ontogenetic and interspecific variation. J Nat Hist 39:3833–3844
Bruce MJ, Herberstein ME, Elgar MA (2001) Signalling conflict between prey and predator attraction. J Evol Biol 14:786–794
Bruce MJ, Heiling AM, Herberstein ME (2005) Spider signals: are web decorations visible to birds and bees? Biology Lett 1:299–302
Cain AJ, Sheppard PM (1954) The theory of adaptive polymorphism. Am Nat 88:321–326
Cheng R-C, Yang E-C, Lin C-P, Herberstein ME, Tso I-M (2010) Insect form vision as one potential shaping force of spider web decoration design. J Exp Biol 213:759–768
Craig CL, Wolf SG, Davis LD, Hauber ME, Maas JL (2001) Signal polymorphism in the web-decorating spider Argiope argentata is correlated with reduced survivorship and the presence of stingless bees, its primary prey. Evolution 55:986–993
Eberhard WG (2003) Substitution of silk stabilimenta for egg sacs by Allocyclosa bifurca (Araneae: Araneidae) suggests that silk stabilimenta function as camouflage devices. Behaviour 140:847–868
Eisner T, Nowicki S (1983) Spiderweb protection through visual advertisement: role of the stabilimentum. Science 219:185–187
Hayashi CY, Blackledge TA, Lewis RV (2004) Molecular and mechanical characterization of aciniform silk: uniformity of iterated sequence modules in a novel member of the spider silk fibroin gene family. Mol Biol Evol 21:1950–1959
Herberstein ME (2000) Foraging behaviour in orb-web spiders (Araneidae): do web decorations increase prey capture success in Argiope keyserlingi Karsch, 1878? Austral J Zool 48:217–223
Herberstein ME, Craig CL, Coddington JA, Elgar MA (2000) The functional significance of silk decorations of orb-web spiders: a critical review of the empirical evidence. Biol Rev 75:649–669
Horton CC (1980) A defensive function for the stabilimentum of two orb-weaving spiders (Araneae, Araneidae. Psyche 87:13–20
Li D, Kok LM, Seah WK, Lim MLM (2003) Age-dependent stabilimentum-associated predator avoidance behaviours in orb-weaving spiders. Behaviour 140:1135–1152
McCook HC (1889) American spiders and their spinning work (volume 1). Academy of Natural Sciences, Philadelphia
Olive CW (1980) Foraging specializations in orb-weaving spiders. Ecology 61:1133–1144
Robinson MH, Olazarri J (1971) Units of behavior and complex sequences in the predatory behavior of Argiope argentata (Fabricius): (Araneae: Araneidae). Sm C Zool 65:1–36
Schoener TW, Spiller DA (1992) Stabilimenta characteristics of the spider Argiope argentata on small islands: support of the predator-defense hypothesis. Behav Ecol Sociobiol 31:309–318
Seah WK, Li D (2001) Stabilimenta attract unwelcome predators to orb-webs. P Roy Soc Lond B 268:1553–1558
Starks PT (2002) The adaptive significance of stabilimenta in orb-webs: a hierarchical approach. Ann Zool Fenn 39:307–315
Tolbert WW (1975) Predator avoidance behaviors and web defensive structures in the orb weavers Argiope aurantia and Argiope trifasciata (Araneae, Araneidae. Psyche 82:29–52
Vollrath F, Knight DP (2001) Liquid crystalline spinning of spider silk. Nature 410:541–548
Walter A, Elgar MA (2011) Signals for damage control: web decorations in Argiope keyserlingi (Araneae, Araneidae. Behav Ecol Sociobiol 65:1909–1915
Walter A, Elgar MA (2012) The evolution of novel animal signals: silk decorations as a model system. Biol Rev 87:686–700
Walter A, Elgar MA, Bliss P, Moritz RFA (2008) Wrap attack’ activates web decorating behavior in Argiope spiders. Behav Ecol 19:799–804
Wellenreuther M, Svensson EI, Hansson B (2014) Sexual selection and genetic colour polymorphisms in animals. Mol Ecol 23:5398–5414
Yeh C-W, Blamires SJ, Liao C-P, Tso I-M (2015) Top down and bottom up selection drives variations in frequency and form of a visual signal. Scientific Reports 5:9543. doi:10.1038/srep09543
Acknowledgments
We thank the Deutsche Forschungsgemeinschaft (DFG) and the Australian Research Council (DP0879610) for financial support.
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by: Sven Thatje
Rights and permissions
About this article
Cite this article
Walter, A., Elgar, M.A. Signal polymorphism under a constant environment: the odd cross in a web decorating spider. Sci Nat 103, 93 (2016). https://doi.org/10.1007/s00114-016-1415-7
Received:
Revised:
Accepted:
Published:
DOI: https://doi.org/10.1007/s00114-016-1415-7