We propose a modular formal ontology of the biomedical domain with two components, one for biological objects, corresponding broadly to anatomy, and one for biological processes, corresponding broadly to physiology. The result constitutes what might be described as a joint venture between two perspectives--of so-called three-dimensionalism and four-dimensionalism--which are normally regarded as incompatible. We outline an approach which allows them to be combined together, and provide examples of its application in biomedicine.