Essays on geography and diseases

This dissertation explores how diseases contributed to shape historical institutions and how health and diseases are still affecting modern comparative development. The overarching goal of this investigation is to identify the channels linking geographic suitability to diseases and the emergence of historical and modern insitutions, while tackling the endogenenity problems that traditionally undermine this literature. I attempt to do so by taking advantage of the vast amount of newly available historical data and of the richness of data accessible through the geographic information system (GIS). The first chapter of my thesis, 'Side Effects of Immunities: The African Slave Trade', proposes and test a novel explanation for the origins of slavery in the tropical regions of the Americas. I argue that Africans were especially attractive for employment in tropical areas because they were immune to many of the diseases that were ravaging those regions. In particular, Africans' resistance to malaria increased the profitability of slaves coming from the most malarial parts of Africa. In the second chapter of my thesis, 'Caste Systems and Technology in Pre-Modern Societies', I advance and test the hypothesis that caste systems, generally viewed as a hindrance to social mobility and development, had been comparatively advantageous at an early stage of economic development. In the third chapter, 'Malaria as Determinant of Modern Ethnolinguistic Diversity', I conjecture that in highly malarious areas the necessity to adapt and develop immunities specific to the local disease environment historically reduced mobility and increased isolation, thus leading to the formation of a higher number of different ethnolinguistic groups. In the final chapter, 'Malaria Risk and Civil Violence: A Disaggregated Analysis for Africa', I explore the relationship between malaria and violent conflicts. Using georeferenced data for Africa, the article shows that violent events are more frequent in areas where malaria risk is higher.

Essays in Economic Geography and Long-Term Development

This dissertation has two main themes: first, the economic impact of tourism on cities and, secondly, the determinants of European long-run development, with a focus on the pre-Industrial era. The common thread is the attempt to develop economic geography models that incorporate spatial frictions and are liable to be given empirical content. Chapter 1, written in conjunction with G. Alfredo Minerva, provides an empirical analysis of the relationship between tourism and economic activity across Italian municipalities, and lays down the basic elements of an urban theory of tourism in an a-spatial setting. Chapter 2 extends these ideas to a quantitative urban framework to study the economic impact and the welfare consequences of tourism into the city of Venice. The model is given empirical content thanks to a large collection of data at the Census tract level for the Municipality of Venice, and then used to perform counterfactual policty analysis. In chapter 3, with Matteo Santacesaria, we consider a setting where agents are continuously distributed over a two-dimensional heterogeneous geography, and are allowed to do business at a finite set of markets. We study the equilibrium partition of the economic space into a collection of mutually-exclusive market areas, and provide condition for this equilibrium partition to exist and to be unique. Finally, chapter 4 "The rise of (urban) Europe: a Quantitative-Spatial analysis", co-authored with Matteo Cervellati and Alex Lehner, sets up a quantitative economic geography model to understand the roots of the Industrial Revolution, in an attempt to match the evolution of the European urban network, and the corresponding city-size distribution, over the period A.D. 1000-1850. It highlights the importance of agricultural trade across cities for the emergence of large manufacturing hubs.