Stabilizing selection maintains exuberant colour polymorphism in the spider Theridion californicum (Araneae, Theridiidae)

  title={Stabilizing selection maintains exuberant colour polymorphism in the spider Theridion californicum (Araneae, Theridiidae)},
  author={Peter J. P. Croucher and Geoff S. Oxford and Athena Wai Lam and Rosemary G. Gillespie},
  journal={Molecular Ecology},
Genetically controlled colour polymorphisms provide a physical manifestation of the operation of selection and how this can vary according to the spatial or temporal arrangement of phenotypes, or their frequency in a population. Here, we examine the role of selection in shaping the exuberant colour polymorphism exhibited by the spider Theridion californicum. This species is part of a system in which several distantly related spiders in the same lineage, but living in very different geographical… 

Convergent evolution in the colour polymorphism of Selkirkiella spiders (Theridiidae) from the South American temperate rainforest

A molecular phylogeny supports previous work and shows that the colour polymorphism in Selkirkiella species appears to be a case of convergent evolution of a diverse color polymorphism at the family level.

Spatial and temporal dynamics of exuberant colour polymorphism in the southern cricket frog

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Population structure and dispersal in a patchy landscape: nuclear and mitochondrial markers reveal area effects in the spider Theridion californicum (Araneae: Theridiidae)

Patterns of population structure in a spider restricted to the Pacific coastal strip of North America that exhibits an exuberant colour polymorphism are examined, showing contrasting, gender-specific patterns between these markers that suggest limited dispersal and area effects most likely caused by expansion from refugial habitat patches following land-management changes.

De novo characterization of the gene-rich transcriptomes of two color-polymorphic spiders, Theridion grallator and T. californicum (Araneae: Theridiidae), with special reference to pigment genes

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Coloration in relation to ecology in the Asian spiny-backed spider, Thelacantha brevispina (Araneae, Araneidae) on Moorea, French Polynesia

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An exuberant, undescribed colour polymorphism in Theridion californicum (Araneae, Theridiidae) : implications for a theridiid pattern ground plan and the convergent evolution of visible morphs

It is suggested that selection for polymorphism, combined with constraints imposed by this theridiid ground plan, may have led to the convergent evolution of colour patterns across the family.

Genetics of a colour polymorphism in Theridion grallator (Araneae: Theridiidae), the Hawaiian happy-face spider, from Greater Maui

Theridion grallator, the Hawaiian happy-face spider, a species endemic to four islands in the Hawaiian archipelago, exhibits an exuberant colour and pattern polymorphism involving both the carapace and opisthosoma, which suggests that the polymorphism in this species has evolved for its visual effects.

Portraits of Evolution: Studies of Coloration in Hawaiian Spiders

This work examines how color variation in two spider systems in the Hawaiian Islands can be used to understand evolutionary phenomena at both population and species levels and considers the adaptive radiation of Hawaiian Tetragnatha spiders.


The results suggest that statistically similar frequencies of color morphs among populations of T. grallator may be maintained by some form of balancing selection, and it is speculated that apostatic selection, perhaps mediated by bird predators, may provide the mechanism.


  • G. Oxford
  • Biology
    Evolution; international journal of organic evolution
  • 2005
It is proposed that when allele frequencies of the color morph redimita lie between approximately 0.05 and 0.3, the Δq on q plot is very shallow, so that within this region, where the majority of populations lie, selection is weak and drift is the major force determining local morph frequencies.

Molecular insights into the phylogenetic structure of the spider genus Theridion (Araneae, Theridiidae) and the origin of the Hawaiian Theridion‐like fauna

Results indicate that the Hawaiian Islands were colonised by two independent Theridiinae lineages, one of which originated in the Americas and both lineages have undergone local diversification in the archipelago and have convergently evolved similar bizarre morphs.

Evolution and ecology of spider coloration.

It is argued that the production of color is metabolically costly and is principally maintained by the action of sight-hunting predators, and must be distinguished from true genetic variation for color to be used as an evolutionary tool.

Identifying footprints of directional and balancing selection in marine and freshwater three‐spined stickleback (Gasterosteus aculeatus) populations

To identify targets of natural selection in the three‐spined stickleback genome, 103 microsatellite and two indel markers including expressed sequence tags and quantitative trait loci (QTL)‐associated loci, were genotyped in four freshwater and three marine populations and indicated that a high proportion of loci might be affected by balancing selection and a lower proportion by directional selection.

The neutral assumption and maintenance of colour morph frequency in mangrove snails

The relation of apparent phenotypic conversion to base mutation is outlined, and published allozyme data from a congeneric species give estimates of effective population size similar to those for L. pallescens morphs.

Patterns of differentiation in a colour polymorphism and in neutral markers reveal rapid genetic changes in natural damselfly populations

Inferences about selection obtained by comparing FST values from neutral and adaptive genetic variation are most useful when spatial and temporal data are available from several populations and time points and when such information is combined with other ecological sources of data.