STRUCTURAL COLOUR IN SEAWEEDS

Session

Poster Session Three

Authors

Maria Murace (2), Margot Minju Arnould-Pétré (1, 3), Prof Juliet Brodie (1), Prof Silvia Vignolini (2, 4)

Affiliations

1. Natural History Museum
2. University of Cambridge
3. ISOMer, Nantes Université
4. Max Planck Institute of Colloids and Interfaces

Keywords

structural colour, electron microscopy, polarised optical microscopy, seaweeds, light management

Abstract text

Over millions of years of adaptation, Nature has developed a range of strategies to optimise use of available resources. In the marine world, organisms have evolved to maximise energy uptake from the reduced amount of light that they receive. In particular, several marine algal species have nanostructures in their outermost layers that can selectively reflect and transmit only certain wavelengths, such as the multilayered cuticle in the red alga Chondrus crispus or the opal-like iridescent bodies in the brown alga Ericaria selaginoides. Both these nanostructures produce bright structural colours as consequence of their interference with visible wavelengths, as well as possibly playing a role in light management, for example providing photoprotection or for enhancing photosynthesis. 

In our work, we aim to understand how widespread these nanostructures are among seaweeds and what their role is in light management. Here, we present a study of a variety of nano-architectures in different macroalgae belonging to both green and red algae. Different microscopy techniques are central for the investigation of these structures, from light to electron microscopy. Specifically, polarised optical microscopy and microspectroscopy are essential, non-invasive tools for understanding the source of the structural colour and its development over time, whereas different electron microscopy techniques provide important information on the structure and composition of these architectures. 

The formation and development of these photonic structures may be linked to environmental conditions, such as in light environment, and have a phylogenetic signal. Unraveling these mechanisms is important not only from a biological perspective, such as in understanding the physiological aspects of the structures and the evolutionary patterns among different species, but also as a source of inspiration for novel bio-inspired materials.

References

[1] C. J. Chandler et al. Structural colour in Chondrus crispus. Sci. Rep. 5, 11645. doi: 10.1038/srep11645 (2015).

[2] M. Lopez-Garcia et al. Light-induced dynamic structural color by intracellular 3D photonic crystals in brown algae. Sci. Adv. 4, eaan8917 (2018). doi: 10.1126/sciadv.aan8917

[3] B. Pettifor et al. Dynamic structural colour increases photosynthetic performance in the alga Ericaria selaginoides. Appl. Phyc. 2:1, 31-40 (2021). doi: 10.1080/26388081.2020.1858447