Cell Culture Methods: Pilot whale, dolphin, humpback whale, beaked whale, and sperm whale biopsies were obtained off of the coast of Virginia Beach, Virginia or Beaufort, North Carolina using a remote biopsying dart by members of the Duke University Marine Lab PhD program under permit.  The skin portion of the biopsy was from the blubber and diced the skin into small pieces. Explants were sterilized for 3 seconds in 70% ethanol and plated onto a dry 10 cm tissue culture dish. Once the explants had dried and adhered to the dish, media was added and cell culture was maintained.  Human and cow cells were obtained from the Duke Cell Culture Facility and elephant seal cells from a collaborator. Human fibroblasts were cultured in DMEM containing 10% charcoal stripped Fetal Bovine Serum (Sigma) and 1% penicillin/streptomycin (Life Technologies). Marine mammal and cow fibroblasts were cultured in F-media, a nutrient rich media supplemented with dihydrochloride (VWR) that has proven to maintain the cultures.