That race is a social construct, meaningless outside of a specific time and place, is an idea academics and lay Americans are increasingly familiar with. Yet I have found repeatedly that teaching this concept to undergraduates, graduate students, and colleagues alike requires concrete examples to elucidate this process—perhaps because of the ways constructs make our lived reality feel so natural and inevitable. How is race, a concept so deeply entrenched in the American mind and its institutions, a construct? How is it constructed?

In their book, Skin Color, Power, and Politics in America, Mara C. Ostfeld and Nicole D. Yadon join a growing literature that attempts to explain precisely how this process happens. In demonstrating that skin color is subjective; that it affects life outcomes; and that individuals’ perceptions of their own physical appearance are tied to political beliefs and characteristics, Ostfeld and Yadon dismantle a foundation of the American racial hierarchy—that groups of people can be defined objectively by skin color, which is both stable and bounded. Ostfeld and Yadon’s book builds a theory of race that crosses ethnoracial boundaries and identifies structural features that produce variation by group. In this endeavor, they join pivotal works—like Natalie Masuoka and Jane Junn’s The Politics of Belonging (2013) and Donald Kinder and Cindy Kam’s Us against Them (2010)—that take on the difficult task of explaining behavior across multiple groups while using the same theoretical levers.

The authors argue that race can be conceptualized as the trunk and branches of a tree with many constitutive elements, or “roots,” feeding into its expression (Chapter 2). These roots are variables that readers are likely already familiar with from other scholarship: phenotypical characteristics, socioeconomic status, language, and region of ancestry, to name a few. In their “Roots of Race” conceptualization, Ostfeld and Yadon argue that some roots are more central and pronounced than others in defining racial experience. Skin color is one such taproot but even this large and dominant component of the racial construct “can shift in importance over time, across context, and among groups” (p. 35).

This point, that the elements defining racial meaning may vary by group history and context, helps unify existing ideas about what race is in an increasingly diverse nation. The most convincing theories of racial hierarchy in the United States, I find, consider multiple dimensions of oppression and privilege, explaining the experiences of not just Black and white Americans, but of Asian Americans, Latinos, and other groups as well. Compiling these dimensions under a single theory of racial construction, which anticipates that some elements for some people are more dominant in racial experience, is an innovation—one that scholars engaged in the analysis of multiple racial groups simultaneously like myself should carry with us.

One “root” of race for Ostfeld and Yadon is ethnoracial classification itself (pp. 31-33)—or as I would think of it, identifying which racial indicator an individual selects when asked. The authors argue that this label is but one of many variables that affect racial experience: for instance, skin color may shape experiences above and beyond this categorical identity. I’m persuaded by this point, but left curious about what the authors think, then, leads to self-identification choices themselves. Do we not need to pull from other roots—skin color, experiences with discrimination, governmental definitions, wealth, myths about ancestry—to self-categorize and to categorize others? Is a self-identified racial group more like a low branch in the tree of race—an outcome itself that springs from this conceptualization rather than an input?

Once they have their theory of race outlined, the authors identify two contextual features that produce variation in the contribution of skin color to life outcomes and political attitudes by group: institutional privilege and blurriness of category boundaries (figure 3.4). This concept of “blurriness” is one that is particularly intriguing. Henri Tajfel and John C. Turner once predicted that a group’s perceived boundedness would affect not just identity strength but mobilization strategies (“The Social Identity Theory of Intergroup Behavior,” in Psychology of Intergroup Relation, 1986). When group boundaries are tightly guarded and clearly defined—what Ostfeld and Yadon refer to as “bright”—low-status group members must pursue changes in the hierarchical laws in society to improve their life chances. But, when group boundaries are “blurry,” enterprising members of low-status groups have the option to exit the group, leaving the structural inequities largely intact. This prediction is, in my opinion, an often-overlooked element of Social Identity Theory with implications for movements and policy change. Ostfeld and Yadon build on this theory when they suggest that the blurriness of groups’ boundaries shape the centrality of skin color in individuals’ racial experience. In putting together privilege and boundary clarity, the authors predict outcomes and build expectations for a wide range of groups, including those they are unable to test with their data: Arab, Asian, Black, Latino, Native, and white Americans.

Another innovation of the book is how it builds new measures and collects difficult-to-get data. Ostfeld and Yadon develop a novel interval scale as a self-reported measure of skin tone (self-assessed skin color) and use a spectrophotometer to obtain a measure of machine-rated skin color. The authors approach their measures with normative and ethical care, constantly placing their inquiry within a broader historical context that has regularly measured skin tone with nefarious and violent intent. Ostfeld and Yadon’s thoughtful measures are part of the contribution of their work and, because of their novelty, I was left hoping for more details about them. The spectrophotometer returns a single number identifying skin color, for instance, but skin is irregular; how does the machine deal with imperfections or disturbances like scars, hair, or freckles? How much variation appeared in the interior wrist reading versus the top of the hand? Did self-assessed skin color, or racial group membership, relate more closely to the first reading on the interior wrist or the second on the exterior hand—or did it make no difference?

Following their discussion of measures, the authors provide what I see as the most thought-provoking figure of the book: a distribution of the measures for skin tone by Black, Latino, and white respondents (figure 4.4). While across-group means are distinct on matched measures, the distributional overlap of skin tone by racial group membership is striking, providing an elegant point of evidence to the broader concept that racial categorization is a shifting, fuzzy construct. In my own work, I have found that Americans across racial group most often identify skin color as central to race’s definition in open-ended responses (“Essentialist or Constructivist? Americans’ Understandings of the Meaning of Race,” Allison Anoll, Cindy Kam, and Colette Marcellin). But as becomes obvious from figure 4.4, and throughout Chapters 5 and 6 of Ostfeld and Yadon’s book, skin color not only varies widely among self-identified racial group members but overlaps across membership to a large degree.

The remaining elements of Ostfeld and Yadon’s book consider how both machine-rated and self-assessed skin color relate to socioeconomic status, political ideology, and racialized policy beliefs for the three largest racial groups in the United States. A central finding is that white Americans with machine-rated darker skin report significantly more conservative beliefs with respect to racialized policies—namely, speaking English and police quality. The authors argue this is because whites’ privileged status has been challenged as the nation has diversified, making the boundaries of the group blurrier (p. 148). I’m left wondering whether it is just demographic trends around diversification that are blurring the boundaries of whiteness or whether we must consider a broader set of transformations in the American racial order: changing norms that value diversity (tied in part to historical affirmative action laws), a growing non-white middle and upper class, and increased rates of multi-racial children (see Creating a New Racial Order, 2012, by Jennifer Hochschild, Vesla Weaver, and Traci Burch).

Collectively, Ostfeld and Yadon’s book provides a careful and innovative example of race as a social construct in American life. It is the kind of example I often search for to clarify to students what, exactly, we mean when we say race is socially constructed. I can imagine assigning selections from the book to make these points: race has many constitutive elements that vary over time and by context (Chapter 2); skin color is but one element, and it is one that cannot clearly delineate boundaries between people very well (Chapter 4); group members on the periphery react to threat more strongly when the boundaries of a group are blurry (Chapter 6). These points go a long way in describing the nature of social and political experience in the United States—and we can thank Ostfeld and Yadon for this contribution.