N	Number of protocells in the compartment (no unit)
N0	Initial number of cells
F	Concentration in food molecules in the compartment (mmol·L−1)
F0	Initial concentration of food in the compartment
A1, A2, A3, A4	Concentrations in molecules A1, A2, A3 and A4 in one protocell (mmol·m−3)
A1,C, A2,C, A3,C, A4,C	Concentrations in molecules A1, A2, A3 and A4 in the compartment (mmol·m−3)
Fi	Food input rate in the compartment (mmol·m−3·s−1)
P	Environmental parameter (no unit)
Pt	Period of P oscillations (s)
Pa	Amplitude of P oscillations (no unit)
Df	Constant for food diffusion between protocells and the environment (mmol·s−1·m−2)
V	Volume of a protocell (m3)
D	Constant for diffusion of molecules A1, …, A4 between protocells and the environment (m·s−1)
U1, U2, U3, U4	Rates of active intake molecules A1, …, A4 by protocells (mmol·s−1·m−2)
fm	Constant for the food required for protocell maintenance (mmol·m−3·s−1)
fu	Constant for the food required for active intake of molecules A1, …, A4 (m2)
Gr	Constant for protocell growth ((m3·mmol−1)3)
L	Constant for protocell death probability (mmol−1)
S	Standard deviation of the distribution of change of U1, …, U4 between generations (mmol·s−1·m−2)