Accelerated Innovation and Increased Spatial Diversity of US Popular Culture

At a time of increasing globalization of much popular culture, we observe not a rise but a marked fall in the spatial homogeneity of the popularity of first names across the United States in recent decades. We explain this apparent paradox by calibrating a modified standard model of neutral cultural evolution to the record of first name popularities for the United as a whole since 1900 and across the individual states over the last 50 years. We obtain estimates of both the temporal and spatial diversity of the speed of cultural evolution during the 20th century and early 21st century. We find that the speed of innovation of popular baby names accelerated substantially since the end of the 20th century, increasing the geographic diversity across the United States. This suggests that accelerated innovation can lead to a more heterogeneous cultural landscape, even in the midst of growing globalization.