CONSTRAINT 1: The constraint of constant propagation
P > 0 = ∫ T0dP
P is an extensive variable and is the population's “Wallace pressure”—its total energy output in joules per second.
CONSTRAINT 2: The constraint of constant size
R > 0 = ∫ T0dR
R is an intensive variable and is the population's average energy output expressed in “darwins” or joules per “biomole”.
CONSTRAINT 3: The constraint of constant equivalence
W > 0 = ∫ T0dW
W is an intensive variable and is the population's work rate or its dynamical specific energy, expressed as watts per kilogramme.
μ = dS = (∂S/∂U)V,Ni dU + (∂S/∂V)U,Ni dV +
Σi (∂S/∂ui)U,V,{Nj≠i} dui + Σi (∂S/∂vi)U,V,{Nj≠i} dvi
The Gibbs-Duhem equation for biology
m̅μ = m̅dS = dU + dH - Σi μi(dvi - dmi)
Biology is “the study of those thermodynamic systems that can replace their internal energy”.
dU = Mdt = δQ - dH
Ecology is “the study of the exact processes by which a thermodynamic system replaces its internal energy”.
pdt + mdt = dh + du