This article was presented as the 2008 Wallace Foundation Distinguished Lecture at the annual meeting of the American Educational Research Association in New York City. It argues that, to generate robust and generative theories of human learning and development, researchers must address the range of diversity within human cultural communities. The argument is warranted on implications from brain science regarding human adaptability and on core findings with regard to relations between cognition, perceptions, and emotions, all influenced by broad ecological contexts that influence human functioning. Implications for education are discussed, with examples of research that address fundamental questions of learning through examinations of practices within communities of color. (Contains 4 notes.)