Table 1.

List of symbols used in the main body text in order of appearance.

symbol	physical meaning
r	radial coordinate in cylindrical coordinates
h	distance between no-slip walls in the z direction in experiment, simulation and theory
μ	liquid viscosity
u	liquid velocity field
p	liquid pressure field
rsp	distance between the origin (centre of forcing) and the eddy centre
a	radius of living or model Vorticella depending on context
θ	polar coordinate in cylindrical or spherical coordinates depending on context
ϑ	the co-latitude in cylindrical coordinates ϑ = π −θ
k	permeability used in Brinkman approximation
β	proportionality constant in the definition of k
γE	Euler–Mascheroni constant
ρ	radial coordinate in spherical coordinates
w	width of chamber in simulations
b	length of chamber in simulations
ℓst	the length of the Vorticella stalk
rspl	the eddy size for a sphere located above a single plane boundary