Poverty, discrimination, and other social and economic inequalities have serious consequences for individuals’ physical and mental well-being. Recently, social scientists have collaborated with biological scientists to better understand the mechanisms that reproduce social stratification within and across generations. In this issue of RSF, edited by anthropologist Thomas McDade and sociologist Kathleen Mullan Harris, and a multi-disciplinary group of scholars integrate theory, data, and methods from the social and biological sciences to advance our understanding of how social and biological processes interact to shape individuals’ health outcomes and life chances.
 
Several articles explore the effects of disadvantage and discrimination on individuals’ health. Douglas Massey and colleagues find that residential segregation and concentrated poverty—which disproportionately affects African Americans—contribute to more rapid cellular aging, a condition associated with a higher risk of disorders such as diabetes and heart disease. Bridget Goosby and colleagues track the sleep patterns of adolescents and find that compared to their white peers, African American and biracial youth who report experiencing frequent discrimination have worse sleep, which is associated with longer-term negative physical and mental health outcomes.
 
Other contributors explore the extent to which social and family environments influence biological processes. Yang Qu and colleagues study the cognitive development of Mexican American youth, focusing on the hippocampus, a region of the brain that produces improved memory and learning. They find that teens who were able to navigate between the cultural values of their parents and fitting in with their peers had different hippocampus volume and higher academic achievement. Other researchers explore the relationship between individuals’ genes and their environments.  Melinda Mills and colleagues examine the role of genes in reproductive behavior. They find that while social and behavioral factors are strongly associated with when mothers first give birth and how many children they have, genetic factors are related to other fertility traits, such as childlessness and menopause.
 
The findings in this issue demonstrate the value of integrating the social and biological sciences for understanding how biological mechanisms influence, and are influenced by, socioeconomic conditions and lay the foundation for further advances in biosocial scholarship.
 

Kathleen Mullan Harris is James E. Haar Distinguished Professor of Sociology at the University of North Carolina, Chapel Hill.
 
Thomas W. McDade is Carlos Montezuma Professor of Anthropology at Northwestern University.

Contributors
Allison E. Aiello, Nicola Barban, Jason D. Boardman, Jeanne Brooks-Gunn, Jacob E. Cheadle, Dalton Conley, Benjamin W. Domingue, Louis Donnelly, Lydia Feinstein, Sara Ferrando-Martínez, Andrew J. Fuligni, Sandro Galea, Adriana Galván, Irwin Garfinkel, Bridget J. Goosby, Kathleen Mullan Harris, Margot I. Jackson, Manuel Leal, Douglas S. Massey, Elizabeth McClure, Thomas W. McDade, Sara McLanahan, Melinda C. Mills, Colter Mitchell, Timothy D. Nelson, Daniel A. Notterman, Yang Qu, David H. Rehkopf, Taylor C. Roth, Susan E. Short, Whitney Strong-Bak, Eva H. Telzer, Felix C. Tropf, Brandon Wagner