Tamás Kálmán discovered a pair of univariate polynomials associated to a hypergraph which enumerate its spanning trees by internal and external activity. In joint work with Amanda Cameron, we have extended this to a bivariate polynomial of polymatroids enumerating both activity statistics at once, using lattice point enumeration. On matroids we find that our invariant agrees with the Tutte polynomial, though not in its most obvious basis, and that its coefficients have combinatorial meaning closely tied to the Dawson partition. I will close by speculating on relationships to algebro-geometric constructions for Tutte and related invariants.