Each summer, scores of distinguished biologists from around the world come to the MBL as visiting researchers to collaborate and conduct research. They use marine and other organisms as model systems for their research. In addition to the MBL's year-round research centers, the Whitman Center represents this vibrant visiting research community. Many of the MBL's visiting researchers have been coming to the MBL each year for 20 years or more. Long-time visiting researchers can be designated as Whitman Investigators to acknowledge their role as vital members of the MBL research community.