In this study, I ask: (1) is industry evolution or isomorphism theory a better model for understanding the change (lack-there-of) among founding team demographics over time? (2) Does region moderate which founding team demographics are prevalent and valued? To answer these questions, I analyse the demographic features of Boston and San Francisco Bay area biotechnology founding teams formed over a period of more than 30 years. I then examine whether there is a financial benefit – in terms of the value of their first investment – for having certain demographic features. I find that there are significant differences between Boston and San Francisco in (1) who becomes founders, (2) the rate at and ways in which demographic features evolve over time, and (3) the features of the founding teams that are rewarded by venture capitalists through higher initial investments. My results demonstrate the importance of treating region and industry age as moderators rather than controls.