John Cowdery Kendrew (1917 – 1997) shared the 1962 Nobel Prize in Chemistry with Max Perutz for determining the first atomic structures of proteins using X-ray crystallography. Kendrew's original studies were on the structure of sheep hemoglobin, but when this work stalled, he embarked on a study of myoglobin, an iron-containing protein which is found in muscle fibers and which, like hemoglobin, binds to oxygen but is only a quarter of hemoglobin’s size. His initial source of raw material was horse heart, but the crystals he obtained from these samples were too small for X-ray analysis. Realizing that the oxygen-conserving tissue of diving mammals could offer a better prospect, Kendrew acquired a large chunk of whale meat from Peru. The whale’s myoglobin gave large crystals with clean X-ray diffraction patterns. By 1957, Kendrew was able to obtain an electron density map at 6-Angstrom resolution, and, by 1959, he built an atomic model at 2 Angstrom-resolution.