Updated project metadata. This submission contains datasets from several species used to demonstrate new features in compareMS2 2.0. Tandem mass spectrometry data from California sea lion, chimpanzee, dog, human, rock hyrax, and white-tailed deer sera were graciously provided with permission from an ongoing collaboration with Dr. Michael G. Janech (College of Charleston) as part of the CoMPARe Program (Comparative Mammalian Proteome Aggregator Resource). Specifically, the California sea lion sera were provided by The Marine Mammal Center (Sausalito, CA), the chimpanzee, rock hyrax, and white-tailed deer sera were provided by The Chattanooga Zoo, and the dog serum from Gus (Ohlandt Veterinary Clinic, Charleston, SC). In addition to institutional and NMFS permits and approval, data collection was performed under NIST ACUC MML-AR20-0001. The identification of certain commercial equipment, instruments, software, or materials does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the products identified are necessarily the best available for the purpose.