An understanding of diet is crucial to an understanding of our evolution. Fortunately, new techniques are yielding new paleontological insights into the evolution of human diet. At the time of the divergence of humans and our nearest living relatives, our ancestors probably had a fairly generalized diet perhaps including soft fruits -- the earliest recognized putative hominid Ardipithecus, lacked the thick enamel of later hominids, or the elaborate shearing crests of gorillas. Evidence from Australopithecus afarensis and A. africanus suggest that by about 4 million years ago (Ma), hominids began to include more abrasive or harder foods such as nuts or seeds. These structurally complex foods became progressively more important until about 2.5 Ma, when the hominids split into two different lineages. Paranthropus continued evolving in this specialized direction (at least in South Africa), developing enormous chewing muscles, jaws, and molar teeth well-suited to crushing and grinding hard or tough savanna foods. In contrast, Homo began to evolve away from such specializations; molar teeth decreased in size, and jaws and skulls became more gracile. Enlarged, well-buttressed front teeth suggest an increased emphasis on biting or tearing. These suggest a reduced emphasis on crushing or grinding, with increased dependence on a wider variety of plant products and/or meat. A return to a generalist strategy may have enabled human ancestors to survive changing, less predictable environments of the Pleistocene, and the range of foods we can take today has led to an unprecedented flexibility that may be responsible both for the dispersal and indeed the survival of our lineage.