Po Peng of The University of Melbourne discussed his 2020 Haldane Shortlisted paper “High contrast yellow mosaic patterns are prey attractants for orb‐weaving spiders”, here he talks about his inspiration behind the paper and the importance of adapting to what fieldwork throws at you.
In this research article, I address a surprisingly neglected topic in visual communication. Typically, studies of visual communication focus on how conspecific receivers shape sexual signals, or how predators shape the protective colouration of prey (warning signals and camouflage). In contrast, I ask how the sensory biases of prey shape the evolution of deceptive signals in colour-luring systems. I discover, through a combination of field experiments and phylogenetic comparative studies that the effectiveness of colour-luring to attract prey might be a major driver of the convergent possession of yellow mosaic patterns in phylogenetically divergent orb-weaving spiders. Specifically, I found the adaptive value of variable signalling features (colour, adjacency, and area of individual colour patches) for foraging success, and how these features are associated with the viewing environments. Combined, my discoveries indicate that signal efficacy plays a significant role in the evolution of colour-luring systems outside of a sexual-signalling context. I think our research will stimulate a new focus of research on visual signalling, beyond its well-established role in sexual selection and in prey defence mechanisms.
While this study extended the understanding of visual ecology via the scope of deceptive signals, puzzling features of the colour lure system remained unresolved. On one hand, recalcitrant relationships can be found all over the orb-weaver tree of life, which makes the evolution of characteristics associated with those nodes difficult to study. I am using complexity reduction and target‐capture techniques to gather genome-wide loci to increase the phylogenetic resolution for comparative tests. On the other hand, diverse body colourations can be seen in spiders, but other natural history information such as web architecture and orientation could contribute to the potential for prey luring. I am compiling a more sophisticated dataset describing those characteristics for phylogenetically controlled comparative analyses. The preliminary results provide evidence that spiders living in brighter condition or building vertical webs are more “colourful.”
As a baccalaureate student, I had the opportunity to explore my own research projects while collaborating with other lab members in the field. I was not only introduced to field research techniques of investigating the visual ecology of brightly–coloured spiders and how they attract their prey, but also to the joys and woes of adapting and rethinking a research project. I explored a variety of methods to best answer our research questions, and this process of formulating and rethinking projects was quite valuable, perhaps more so than the fieldwork itself. As an ecologist working in the field frequently, I need to make amendments when bungling the procedure or disturbed by a weather event such as typhoon. The sense of fulfilment brought when solving problems under arduous conditions is ineffable. After receiving a national–level, best student verbal presentation award for my baccalaureate final research project awarded by the Biology Society of the Republic of China (Taiwan, ROC.), I decided to pursue a career in ecological & evolutionary research and look forward to extending my research comprehensively, and thus I came to the University of Melbourne studying PhD under the supervision of Mark Elgar and Devi Stuart-Fox. My dissertation focused on investigating the adaptations of behavioural traits and their evolutionary implications on interspecific interactions. I am currently employed as a senior bioinformatician in a next generation sequencing company in Taiwan, using metagenomics data to characterise microbiome compositional and functional changes, and developed pipelines to investigate evolutionary patterns and assemblages crossing broad-scale in space and taxonomy.
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