Have you ever wondered how algae stay so clean, even though most non-living surfaces gather ¿dirt¿ and biofilm? Well, most flowering-plant leaves also stay clean. Under air, water and ¿dirt¿ films are repelled. Repulsion forces the water into droplets that easily roll off because these leaves are covered in hydrophobic nm- to µm- sized grooves and pillars, producing superhydrophobicity (SH) at the surface. Similarly, most algal cells bear a glycocalyx of organic fibrils that give surface structure, and are often hydrophobic. Glycocalyxes serve many functions, but whether they produce SH is poorly known. HAB diatom and dinoflagellate cultures were recently shown to reduce viscosity in laminar capillary flow, possibly by SH drag reduction, a phenomenon now well know from laminar flow in SH capillaries. SH coatings are being developed to prevent fouling of ships and aquaculture structures without using toxins, so this technology could help understand how algae defeat fouling. Glycocalyxes are composed of exopolymeric substances (EPS), and algae sometimes make the water more viscous using this tightly and more loosely bound EPS. EPS is also sometimes sticky. Copepods (water fleas) have to spend time scraping sticky algal cells off their feeding appendages. Can SH cuticles on copepods help defeat sticky algal sabotage? On cells generally, glycocalyxes also serve in immunological-type recognition, binding and sensing. This may allow algae the tools to discriminate in their engineering of ambient fluidics, as part of their environment. More data are required of how organisms modify the rheological properties of ocean water and nano/microfluidics for models of how the ocean is responding to environmental change. A working group exists in this field, interested scientists and welcome to make contact

Jenkinson, Ian R. ... et. al.-- 10 th Annual European Rheology Conference (AERC), 50 th Annual Meeting of the Groupe Français de Rhéologie, Golden Jubilee Meeting of the Groupe Français de Rhéologie, 14-17 April 2015, Nantes

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