Light Science and Optics of Glowworms and their Snares

Project Level:  Honours

Glowworms (GWs) attract prey to the blue green light they produce and emit. Prey are caught in a snare of silk threads decorated with teardrop shaped sticky droplets. In common with the webs of many spider species, the elements of the snare are transparent. They can be regarded as optical materials in addition to being mechanical materials with strength and toughness. Self-assembled, transparent optics, as used by some animals like GWs, are a rich source to explore for biomimetic purposes.  A/Prof Merritt is an expert on GW biology. His research has led to successful housing of GWs in the lab so that they can be the subjects of systematic study. This creates the opportunity for quantitative physical measurements to be carried out in the laboratory. Significant questions about whether the light emitted by GWs is polarised or partially polarised, the intensity distribution of the emitted light, and, whether the optics of the snare may have a role other than being transparent will be addressed. This project is well-sized and scoped for a complete research experience at honours level. It will support the development of creative thinking; experiment planning, commissioning and completion skills; building capability in analysis and interpretation of results, collaboration skills, communication skills, and, if the student chooses, building interdisciplinary knowledge. Theoretically oriented aspects pertaining to the optics can also be included. This is original research. Background on GW research focussed on mechanical properties, and, examples of research on biological optics – spider silk – are given to indicate the type of papers that might ultimately derive from such research.   

References

1. “Biomechanical properties of fishing lines of the glowworm Arachnocampa luminosa (Diptera; Keroplatidae”, J. von Byern etal, (2019) Scientific Reports 9:3082. https://doi.org/10.1038/s41598-019-39098-1

2. “Image contrast immersion method for measuring refractive index applied to spider silks”, D. J. Little and D. M. Kane,  (2011), Optics Express, Vol. 19 Issue 20, pp.19182-19189.

3. “Hybrid polarization-immersion method for measuring birefringence applied to spider silks”, D. J. Little and D. M. Kane, (2011) Optics Letters, Volume: 36   Issue: 20   pp. 4098-4100.

4. “Sub-diffraction ¬limited radius measurements of microcylinders using conventional bright¬field optical microscopy”, D. J. Little and D. M. Kane (2014) Optics Letters 39  Issue 17,  pp. 5196¬5199  DOI: 10.1364/OL.39.005196

5. “Investigating the transverse optical structure of spider silk micro-fibers using quantitative optical microscopy”, D. J. Little and D. M. Kane (2017) Nanophotonics, 6, 341-348.