Final answer:
The Leakey family of British anthropologists conducted important research on human evolution in Kenya and Tanzania, particularly in the Eastern Rift Valley.
Step-by-step explanation:
The Leakey family of British anthropologists is well-known for their significant contributions in the study of human evolution, particularly in Kenya and Tanzania. Louis Leakey and his wife, Mary Leakey, conducted extensive research in the Eastern Rift Valley of East Africa, where they discovered important hominin fossils, including Paranthropus boisei. Their work has greatly advanced our understanding of human origins and early human development.