Table 1. Variables and parameters, see Appendix for nondimensional scalings.

State variables:
N	number of cells in local population
B	number of molecules of metabolic factor outside of cells
I	number of molecules of metabolic factor within each cell
t	nondimensional time scale
Control variables:
α	external uptake rate of metabolic factor
γ	internal synthesis rate of metabolic factor
Parameters:
a	cost for uptake via diminished population growth rate
g	cost for synthesis via diminished population growth rate
d	intrinsic cellular death rate
p	loss rate of internal molecules of metabolic factor
v	extrinsic inflow of metabolic factor
m	loss rate of external molecules of metabolic factor
u	patch death rate, with average patch survival 1∕u
Other processes: (see Appendix)
c	scaling for molecules of metabolic factor released at death
k	scaling for molecules of metabolic factor taken up by cells