To determine which of the options is not something a geographer can explain to a historian, we need to understand the focus of each discipline.
Geography primarily studies the spatial distribution of phenomena and the relationships between people and their environment. Historians, on the other hand, examine past events, cultural developments, and human actions over time.
A. Why people populated certain areas: Geographers can explain this by studying factors such as resources, climate, terrain, and transportation routes that influenced human settlement patterns.
B. How people change their environment: Geographers study how people modify and impact their surroundings through activities such as agriculture, urbanization, deforestation, and infrastructure development. This understanding can help historians comprehend changes in human settlements and societies.
C. How the environment changes people: Geographers can analyze how environmental conditions, such as climate, natural disasters, and access to resources, shape human behaviors, cultures, and societal development.
D. Why people like other people: This option relates more to social interactions, relationships, and individual preferences, which fall more under the realm of psychology and anthropology than geography.
Therefore, the correct answer is D. A geographer may not be able to provide insights on why people like other people, as it pertains more to psychological and sociological aspects of individuals and relationships.