Final answer:
A scientist digging up a fossil human ancestor is working in the field of paleoanthropology, which involves excavation and analysis of fossils to understand human evolution.
Step-by-step explanation:
A scientist who is carefully digging up a fossil human ancestor is participating in the discipline of paleoanthropology, which is a branch of paleontology focused on the study of early humans. Paleoanthropologists conduct excavation to uncover fossils and use them along with ancient material culture to understand human evolution. This type of fieldwork is crucial for gathering the physical evidence necessary to form hypotheses about our predecessors and how they lived. The process is meticulous and often involves lengthy periods of digging in challenging conditions to expose and protect fossils before they can be analyzed further for research purposes.