Nephila spider male aggregation : preference for optimal female size and web clustering

Kuntner, Matjaž (author), Kuntner, Maj (author), Kuntner, Eva (author), Kuntner, Irena (author), Faganeli Pucer, Jana (author), Štrumbelj, Erik (author), Li, Daiqin (author)

Sexual size dimorphism theory predicts biased operational sex ratios (OSRs) and an uneven distribution of males among certain females. We studied this phenomenon through a field census of the giant wood spider Nephila pilipes (family Nephilidae) in Singapore, a species where females are, on average, 6.9 times larger than males. Specifically, we tested two hypotheses concerning male distribution, given their tendency to aggregate in certain female webs. The optimal female size hypothesis predicts that males would predominantly occupy webs of intermediate-sized females. The web clustering hypothesis posits that more males would be found in webs closer together compared to those farther apart. Our snapshot census revealed a female-biased OSR (females: males = 1.85) with an uneven distribution of males in female webs. Most males were found in webs of intermediate-sized females aligning with the optimal female size hypothesis. Proximity among female webs was indicative of male presence, lending support to the web clustering hypothesis. While our study's limited sample size warrants caution, we conclude that in N. pilipes, male occupation of female webs is facilitated by the clustering of webs, and males prefer to cohabit with optimally sized, receptive females.

• Language: English
• Keywords: sexual size dimorphism, operational sex ratios, OSRs, male distribution, optimal female size hypothesis, web clustering hypothesis, female-biased OSR, intermediate-sized females, proximity of webs, male aggregation, arachnology, behavioral ecology, environmental zoology, eSSD, Nephila pilipes, sexual selection, sexual size dimorphism
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FRI - Faculty of Computer and Information Science
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: Str. 793–799
• Numbering: Vol. 20, iss. 4
• PID: 20.500.12556/RUL-175980
• UDC: 591
• ISSN on article: 1749-4877
• DOI: 10.1111/1749-4877.12896
• COBISS.SI-ID: 206219267
• Publication date in RUL: 17.11.2025

Record is a part of a journal

• Title: Integrative zoology
• Shortened title: Integr. zool.
• Publisher: Wiley, International Society of Zoological Sciences, Chinese Academy of Sciences, Institute of Zoology
• ISSN: 1749-4877
• COBISS.SI-ID: 517732889

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• License: CC BY-NC 4.0, Creative Commons Attribution-NonCommercial 4.0 International
• Link: http://creativecommons.org/licenses/by-nc/4.0/
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