Prejudice as a Response to Perceived Group Threat: Population Composition and Anti-Immigrant and Racial Prejudice in Europe (1995)
Author: Lincoln Quillian
“I extend and test a theory of prejudice abased on perceived threats to dominant racial or national groups by subordinate groups. Perceived threat is hypothesized to be a function of economic conditions and of the size of the subordinate group relative to the dominant group. I test the group-threat theory using a multilevel model that combines population data with survey results on attitudes towards immigrants and racial minorities from Eurobarometer Survey 30. “Group threat” explains most of the variation in average prejudice scores across the 12 countries in the sample and has a small but statistically significant effect on the influence of certain individual-level variables on prejudice. These results demonstrate the importance of perceived intergroup threat in the formation of prejudicial attitudes and suggest a re-interpretation of past findings on the relations between individual characteristics and expressions of prejudice.”
Source: http://www.jstor.org/stable/2096296

Is Collective Violence Correlated with Social Pluralism? (1997)
Author: Rudolph J. Rummel
Increasing social pluralism (diversity) is correlated with increased chance of collective violence.
Source: https://www.jstor.org/stable/425106?seq=1#page_scan_tab_contents

What Makes Teams Work: Group Effectiveness Research from the Shop Floor to the Executive Suite (1997)
Authors: Susan G. Cohen, Diane E. Bailey
Ethnically diverse workplaces have lower cohesion, lower satisfaction and higher turnover.
Source: http://jom.sagepub.com/content/23/3/239.short?rss=1&ssource=mfc

Does Social Capital Have an Economic Payoff? A Cross-Country Investigation (1997)
Authors: Stephen Knack, Philip Keefer
“Memberships in formal groups—Putnam's measure of social capital—is not associated with trust or with improved economic performance. We find trust and civic norms are stronger in nations with higher and more equal incomes, with institutions that restrain predatory actions of chief executives, and with better-educated and ethnically homogeneous populations.”
Source: https://academic.oup.com/qje/article-abstract/112/4/1251/1911732

Participation in Heterogeneous Communities (2000)
Authors: Alberto Alesina, Eliana La Ferrara
“Using survey data on group membership and data on U. S. localities, we find that, after controlling for many individual characteristics, participation in social activities is significantly lower in more unequal and in more racially or ethnically fragmented localities.”
Source: http://qje.oxfordjournals.org/content/115/3/847.abstract

Cowards and Heroes: Group Loyalty in the American Civil War (2001)
Authors: Dora L. Costa, Matthew E. Kahn
Homogeneous military units have less desertion than diverse units.
 http://www.nber.org/papers/w8627

UNDERSTANDING THE AMERICAN DECLINE IN SOCIAL CAPITAL, 1952-1998 (2003)
Authors: Dora L. Costa, Matthew E. Kahn
“Rising community heterogeneity (particularly income inequality) explains the fall in social capital produced outside the home.”
Source: http://www.econ.ucla.edu/costa/scapital8.pdf

The persistence of white ethnicity in New England politics (2004)
Author: James G. Gimpela, Wendy K. Tam Cho
As an explanation of recent voting behavior, ethnic origin trumps class differences. “…the political salience of white ethnicity persists, suggesting that ethnic groups do not simply dealign or politically “assimilate” over time.
Source: http://www.sciencedirect.com/science/article/pii/S0962629804000642

Predicting Cross-National Levels of Social Trust: Global Pattern or Nordic Exceptionalism? (2005)
Authors: Jan Delhey, Kenneth Newton
Ethnic homogeneity and Protestant traditions positively impact individual and societal levels of social trust.
Source: https://academic.oup.com/esr/article-abstract/21/4/311/556895/Predicting-Cross-National-Levels-of-Social-Trust

The New Separate But Equal (2005)
Author: James Chen
In the most liberal region in the US, San Francisco and surrounding suburbs, White parents are pulling their kids out of public schools that are becoming increasingly asian.
Source: http://www.americanthinker.com/articles/2005/12/the_new_separate_but_equal.html

E Pluribus Unum: Diversity and Community in the Twenty-first Century (2006)
Diversity reduces voter registration, political efficacy, charity, and number of friendships. Ethnic diversity reduces happiness and quality of life. Diversity reduces trust, civic participation, and civic health. Diversity reduces charity and volunteering. People who live in diverse communities rather than homogenous ones are poorer and less educated. Black people trust their neighbors less than do White people. Spanish speakers trust their neighbors less than do English speakers. Asians trust their neighbors less than do White people. Ethnic diversity among members of the same race reduces infrastructure quality, charity, and loan repayment. Diversity of any sort makes people more likely to defect in game theoretic scenarios.

Trust, Inequality and Ethnic Heterogeneity (2006)
Authors: ANDREW LEIGH
“Using a large Australian social survey, combined with precise data on neighbourhood characteristics, I explore the factors that affect trust at a local level (‘localised trust’) and at a national level (‘generalised trust’). Trust is positively associated with the respondent's education, and negatively associated with the amount of time spent commuting. At a neighbourhood level, trust is higher in affluent areas, and lower in ethnically and linguistically heterogeneous communities, with the effect being stronger for linguistic heterogeneity than ethnic heterogeneity. Linguistic heterogeneity reduces localised trust for both natives and immigrants, and reduces generalised trust only for immigrants. Instrumental variables specifications show similar results. In contrast to the USA, there is no apparent relationship between trust and inequality across neighbourhoods in Australia.”
Source: http://onlinelibrary.wiley.com/doi/10.1111/j.1475-4932.2006.00339.x/full

When Does Diversity Erode Trust? Neighborhood Diversity, Interpersonal Trust and the Mediating Effect of Social Interactions (2008)
Authors: Dietlind Stolle, Stuart Soroka, Richard Johnston
“Our analysis, one of the first controlled cross-national comparisons of small-unit contextual variation, confirms recent findings on the negative effect of neighborhood diversity on white majorities across the two countries.”
Source: http://www.snsoroka.com/files/2008StolleSorokaJohnston.pdf

The Effect of Ethnic Diversity and Community Disadvantage on Social Cohesion: A Multi-Level Analysis of Social Capital and Interethnic Relations in UK Communities (2009)
Author: James Laurence
“Our results show that while increasing diversity does have a negative impact on social capital, it simultaneously improves perceptions of, and relations between, ethnic groups. Furthermore, we find that forming ‘bridging’ ties in diverse environments plays a significant role in the positive relationship between diversity and tolerance, and that the presence of ‘bridging’ ties can also reduce the negative impact of diversity on social capital. However, while our results show that diversity has both positive and negative effects on social cohesion, we find that it is disadvantage which has the most detrimental impact, undermining both social capital and interethnic relations.”
Source: https://academic.oup.com/esr/article-abstract/27/1/70/448535

ETHNIC DIVERSITY AND TRUST (2010)
Author: OGUZHAN C. DINCER
“I find a negative relationship between ethnic polarization and trust and a U-shaped relationship between ethnic fractionalization and trust. According to my estimations, (a) going from an ethnic polarization index (PI) of 0 to an ethnic PI of 1 decreases trust by almost 12% points;”
Source: http://onlinelibrary.wiley.com/doi/10.1111/j.1465-7287.2010.00215.x/abstract

School Choice, Universal Vouchers and Native Flight from Local Schools (2010)
Authors: Beatrice Schindler Rangvid
Using data from Copenhagen school registers, researchers found that native Danes opt out of public schools when the immigrant population concentration hits 35% or more.
Source: http://emilkirkegaard.dk/en/wp-content/uploads/School-Choice-Universal-Vouchers-and-Native-Flight-from-Local-Schools.pdf

Ethnic, Religious and Economic Diversity in Dutch Neighbourhoods: Explaining Quality of Contact with Neighbours, Trust in the Neighbourhood and Inter-Ethnic Trust (2011)
Authors: Bram Lancee, Jaap Dronkers
“Besides ethnic diversity, we identify economic and religious diversity, as well as language proficiency in the neighbourhood. This study explores data from the Netherlands showing how these four dimensions of diversity in the neighbourhood affect the quality of contact with neighbours, trust in the neighbourhood and inter-ethnic trust for immigrant and native residents. We find that ethnic diversity in the neighbourhood still lowers the quality of contact with neighbours. For natives, ethnic diversity is positively associated with inter-ethnic trust, whereas for immigrants there is no effect. Furthermore, for natives, religious diversity negatively affects the quality of contact with neighbours and inter-ethnic trust, whereas for immigrants this effect is positive. Economic diversity positively impacts on trust in the neighbourhood and inter-ethnic trust. We do not find an effect of language proficiency.”
Source: http://www.tandfonline.com/doi/abs/10.1080/1369183X.2011.545277

Good Fences: The Importance of Setting Boundaries for Peaceful Coexistence (2011)
Authors: Alex Rutherford, Dion Harmon, Justin Werfel, Shlomiya Bar-Yam, Alexander Gard-Murray, Andreas Gros, Yaneer Bar-Yam
Borders, not multiculturalism, reduce intergroup violence.
Source: http://arxiv.org/abs/1110.1409

Patterns of Racial-Ethnic Exclusion by Internet Daters (2011)
Authors: Belinda Robnett, Cynthia Feliciano
Exclusionary dating is a natural consequence of racial diversity.
Source: https://academic.oup.com/sf/article-abstract/89/3/807/2235576/Patterns-of-Racial-Ethnic-Exclusion-by-Internet?redirectedFrom=fulltext

Disentangling the ‘New Liberal Dilemma’: On the relation between general welfare redistribution preferences and welfare chauvinism (2012)
Authors: Tim Reeskens, Wim van Oorschot
“In the present ‘Age of Migration’, public policy as well as social scientists are puzzled by the ‘New Liberal Dilemma’ (Newton, 2007) of finding popular support for welfare programs that have been installed in times of cultural homogeneity… we show that particularly those who favor that welfare benefits should in the first place target the neediest, place the highest restrictions on welfare provisions for immigrants. In addition, the relationship between preferences for welfare redistribution and opinions about immigrants’ access to social welfare is moderated by a national context of cultural heterogeneity.”
Source: http://journals.sagepub.com/doi/abs/10.1177/0020715212451987

Ethnic Conflicts: Their Biological Roots in Ethnic Nepotism (2012)
Author: Tatu Vanhanen
“[E]thnic heterogeneity [diversity] explains 55% of the variation in the scale of ethnic conflicts, and the results of regression analysis disclose that the same relationship more or less applies to all 187 countries. … [E]thnic nepotism is the common cross-cultural background factor which supports the persistence of ethnic conflicts in the world as long as there are ethnically divided societies.”
Source: http://www.scirp.org/reference/ReferencesPapers.aspx?ReferenceID=1251240

Ethnic density as a buffer for psychotic experiences: findings from a national survey (EMPIRIC) (2012)
Authors: Jayati Das-Munshi, Laia Bécares, Jane E. Boydell, Michael E. Dewey, Craig Morgan, Stephen A. Stansfeld, Martin J. Prince
Diversity increases psychotic experiences, social adversity. More true among minorities than white British.
Source: http://bjp.rcpsych.org/content/201/4/282.full

Environmental Performance in Socially Fragmented Countries (2012)
Author: Elissaios Papyrakis
Ethnic diversity reduces concern for the environment.
Source: http://link.springer.com/article/10.1007%2Fs10640-012-9619-6

Trust in a Time of Increasing Diversity: On the Relationship between Ethnic Heterogeneity and Social Trust in Denmark from 1979 until Today (2012)
Authors: Peter Thirsted Dinsen, Kim Mannemar Sønderskov
Social trust is negatively affected by ethnic diversity, case study in Denmark from 1979 to the present.
Source: http://onlinelibrary.wiley.com/doi/10.1111/j.1467-9477.2012.00289.x/abstract

A revealing map of the world’s most and least ethnically diverse countries (2013 or 2002)
Author: Max Fisher, or Alberto F. Alesina, William Easterly, Arnaud Devleeschauwer, Sergio Kurlat, Romain T. Wacziarg
Diversity correlates with lower GDP per capita. Strong democracy correlates with ethnic homogeneity.
Source: https://www.washingtonpost.com/news/worldviews/wp/2013/05/16/a-revealing-map-of-the-worlds-most-and-least-ethnically-diverse-countries/ or https://papers.ssrn.com/sol3/papers.cfm?abstract_id=319762

Competitive Threat, Intergroup Contact, or Both? Immigration and the Dynamics of Front National Voting in France (2013)
Author: Daniel J. Della Posta
Diversity is associated with more White support for nationalist parties, except at the local level where large immigrant populations cut into vote totals for nationalist parties.
Source: https://academic.oup.com/sf/article-abstract/92/1/249/2235758/Competitive-Threat-Intergroup-Contact-or-Both?redirectedFrom=fulltext

ETHNIC DIVERSITY AND ITS IMPACT ON COMMUNITY SOCIAL COHESION AND NEIGHBORLY EXCHANGE (2013)
Authors: REBECCA WICKES, RENEE ZAHNOW, GENTRY WHITE, LORRAINE MAZEROLLE
In Australia, ethnic diversity lowers social cohesion and increases “hunkering”, providing support for Putnam’s thesis finding the same results in the US.
Source: http://onlinelibrary.wiley.com/doi/10.1111/juaf.12015/abstract

J.P. Rushton’s theory of ethnic nepotism (2013)
Authors: Frank Salter, Henry Harpending
Genetic Similarity Theory (GST) could help explain why diverse groups in close proximity increases ethnic conflict and ethnic nepotism.
Source: http://www.sciencedirect.com/science/article/pii/S0191886912005569

The Evolutionary Dominance of Ethnocentric Cooperation (2013)
Authors: Max Hartshorna, Artem Kaznatcheeva, Thomas Shultz
Recent agent-based computer simulations suggest that ethnocentrism, often thought to rely on complex social cognition and learning, may have arisen through biological evolution. From a random start, ethnocentric strategies dominate other possible strategies (selfish, traitorous, and humanitarian) based on cooperation or non-cooperation with in-group and out-group agents. Here we show that ethnocentrism eventually overcomes its closest competitor, humanitarianism, by exploiting humanitarian cooperation across group boundaries as world population saturates.
Source: http://jasss.soc.surrey.ac.uk/16/3/7.html

The (In)compatibility of Diversity and Sense of Community (2013)
Authors: Zachary & Jennifer Neal
Ethnic diversity directly reduces strong communities. Homogeneous polities have less crime, less civil war, and more altruism.
Source: https://www.msu.edu/~zpneal/publications/neal-diversitysoc.pdf or http://link.springer.com/article/10.1007%2Fs10464-013-9608-0

Cooperation in Ethnically Diverse Neighborhoods: A Lost-Letter Experiment (2013)
Authors: Ruud Koopmans, Susanne Veit
“We conducted a field experiment based on the lost-letter technique across 52 neighborhoods in Berlin, Germany. The study has two aims. First, we investigate whether the negative effect of ethnic heterogeneity on cooperation holds for concrete cooperative behavior in a real-world setting. Second, we test the most prominent psychological mechanism that has been proposed to explain the negative effects of heterogeneity on cooperation, namely in-group favoritism. We do so by experimentally varying the ethnicity and religion of the senders of letters. We find strong support for the negative effect of ethnic diversity on cooperation. We find no evidence, however, of in-group favoritism. Letters from Turkish or Muslim organizations were as often returned as those from German and Christian organizations, and the ethnic diversity effect was the same for all types of letters.”
Source: http://onlinelibrary.wiley.com/doi/10.1111/pops.12037/full

Ethnic Diversity, Economic and Cultural Contexts, and Social Trust: Cross-Sectional and Longitudinal Evidence from European Regions, 2002–2010 (2014)
Author: Conrad Ziller
“In longitudinal perspective, [across European regions] an increase in immigration is related to a decrease in social trust… Immigration growth is particularly strongly associated with a decrease in social trust in contexts of economic decline and high ethnic polarization.”
Source: https://academic.oup.com/sf/article-abstract/93/3/1211/2332107/Ethnic-Diversity-Economic-and-Cultural-Contexts

Ethnic diversity, trust, and the mediating role of positive and negative interethnic contact: A priming experiment (2014)
Authors: Ruud Koopmans, Susanne Veit
In Germany, residential diversity reduces natives’ trust in neighbors, while it also reduces immigrants’ trust but through a different pathway.
Source: http://www.sciencedirect.com/science/article/pii/S0049089X1400074X

School ethnic diversity and White students’ civic attitudes in England (2014)
Author: Jan German Janmaat
After controlling for a self-selection bias, study finds that ethnic diversity in English schools reduces trust in same-age people and does not make White British students more inclusive in their attitudes towards immigrants.
Source: http://www.sciencedirect.com/science/article/pii/S0049089X14001392

Ethnic Diversity and Social Capital in Indonesia (2015)
Author: Dimitris Mavridis
“This paper uses the variations of ethnic diversity between districts in Indonesia to show that diversity leads to lower social capital outcomes. I find that distinguishing between ethnic polarization and fractionalization matters for the results, as polarization has a larger negative effect. The results cannot entirely be attributed to selection on unobservables, and at least part of the relationship should be interpreted as causal. Finally, diversity seems to increase tolerance, despite its negative effect on other social capital variables such as trust, perceived safety, and participation to community activities, and voting in elections.”
Source: http://www.sciencedirect.com/science/article/pii/S0305750X1400343X

Does Ethnic Diversity Have a Negative Effect on Attitudes towards the Community? A Longitudinal Analysis of the Causal Claims within the Ethnic Diversity and Social Cohesion Debate (2015)
Authors: James Laurence, Lee Bentley
Ethnic diversity causally decreases social cohesion.
Source: http://esr.oxfordjournals.org/content/early/2015/08/20/esr.jcv081.full

Effects of Heterogeneity and Homophily on Cooperation (2015)
Author: Ozan Aksoy
“The results show that heterogeneity hampers between-group cooperation at the dyadic level.”
Source: http://journals.sagepub.com/doi/abs/10.1177/0190272515612403

Ethnic Diversity and Social Trust - Evidence from the Micro-Context (2015)
Authors: Peter Thirsted Dinsen, Kim Mannemar Sønderskov
Ethnic diversity within 80 meters of a person reduces social trust.
Source: http://asr.sagepub.com/content/early/2015/04/20/0003122415577989.abstract

Internal dissension cited as reason for Cahokia’s dissolution (2015)
Authors: Thomas E. Emerson, Kristin M. Hedman
Internal dissension stoked by ethnic, social, political, and religious diversity, rather than environmental degradation, caused the collapse of the urbanized Cahokia Indian Tribe.
Source: https://archaeologynewsnetwork.blogspot.nl/2016/02/internal-dissension-cited-as-reason-for.html

Melting pot or salad bowl: the formation of heterogeneous communities (2015)
Authors: Arun Advani, Bryony Reich
The numbers and the genetic distance matter. Minority groups that get above a certain critical mass, and that are culturally distant from the majority culture, begin to self-segregate from the majority, moving society toward division and away from cooperation.
Source: https://www.ifs.org.uk/uploads/publications/wps/WP201530.pdf

The Most Diverse Cities Are Often The Most Segregated (2015)
Author: Nate Silver
In America, more diverse cities have more segregation.
Source: http://fivethirtyeight.com/features/the-most-diverse-cities-are-often-the-most-segregated/

The Nature of Conflict (2015)
Authors: Cemal Eren Arbatli, Quamrul H. Ashraf, Oded Galor
Genetic diversity has contributed significantly to frequency of ethnic civil conflict, intensity of social unrest, growth of unshared policy preferences, and economic inequality over the last half-century.
Source: https://www.nber.org/papers/w21079

Can a Potluck Make You Not Want to Move? (2016)
Author: Melody Warnick
A sense of social cohesion with the people who live around us is as happiness-inducing as love for the place itself.
Source: https://www.psychologytoday.com/blog/is-where-you-belong/201603/can-potluck-make-you-not-want-move

Diversity and innovation (2016)
Authors: Bala Ramasamy, Matthew C. H. Yeung
High ethnic diversity has a negative effect on innovation, but high “values diversity” has the opposite effect, as long as ethnic diversity is low. The best innovation happens in countries that are ethnically homogenous but diverse in values orientation.
Source: http://www.tandfonline.com/doi/abs/10.1080/13504851.2015.1130785

Diversity Policies Rarely Make Companies Fairer, and They Feel Threatening to White Men (2016)
Authors: Tessa L. Dover, Brenda Major, Cheryl R. Kaiser
Company diversity policies don’t help minorities or women, and they psychologically discriminate against White men.
Source: https://hbr.org/2016/01/diversity-policies-dont-help-women-or-minorities-and-they-make-white-men-feel-threatened

Does Ethnic Diversity Have a Negative Effect on Attitudes towards the Community? A Longitudinal Analysis of the Causal Claims within the Ethnic Diversity and Social Cohesion Debate (2016)
Authors: James Laurence
A longitudinal test of the impact of diversity finds that it makes existing residents feel unhappier and more socially isolated.
Source: https://www.academia.edu/3479330/Does_Ethnic_Diversity_Have_a_Negative_Effect_on_Attitudes_towards_the_Community_A_Longitudinal_Analysis_of_the_Causal_Claims_within_the_Ethnic_Diversity_and_Social_Cohesion_Debate

Does Gender Diversity Promote Nonconformity? (2016)
Author: Makan Amini, Mathias Ekström, Tore Ellingsen, Magnus Johannesson, Fredrik Strömsten
Gender diversity does not promote nonconformity in decision-making bodies. (But individual ability diversity does.)
Source: http://pubsonline.informs.org/doi/abs/10.1287/mnsc.2015.2382

In Search of the Key to Closing Achievement Gaps (2016)
Author: Michael Hansen
School integration (forced proximate Diversity) will not close race achievement gaps.
Source: https://www.usnews.com/opinion/knowledge-bank/articles/2016-01-08/the-academic-benefit-of-reducing-school-segregation-may-be-overblown

The Impact of Adolescents' Classroom and Neighborhood Ethnic Diversity on Same- and Cross-Ethnic Friendships Within Classrooms (2016)
Authors: Anke Munniksma, Peer Scheepers, Tobias H. Stark, Jochem Tolsma
Greater classroom and neighborhood diversity is linked to stronger tendencies to choose same-ethnic rather than cross-ethnic friends.
Source: http://onlinelibrary.wiley.com/doi/10.1111/jora.12248/abstract

New study finds our desire for 'like-minded others' is hard-wired (2016)
Author: Angela J. Bahns et al.
Our desire for ‘like-minded others’ is hard-wired.
Source: https://medicalxpress.com/news/2016-02-desire-like-minded-hard-wired.html

Racial Identity, and Its Hostilities, Are on the Rise in American Politics (2016)
Author: Eduardo Porter
As diversity increases, politics becomes more tribalistic.
Source: https://www.nytimes.com/2016/01/06/business/economy/racial-identity-and-its-hostilities-return-to-american-politics.html?_r=1

The Great Houston Flood Of 2016 And The Consequences of Minority Rule (2016)
Growing racial diversity in Houston is contributing to declining construction standards and aggravating the impact of natural disasters.
Source: http://www.amerika.org/politics/the-great-houston-flood-of-2016-and-the-consequences-of-minority-rule/

This model of wealthy suburban living is starting to fray (2016)
Author: Antonio Olivo
A wealthy Virginia county that is rapidly racially diversifying is getting poorer and less socially cohesive.
Source: https://www.washingtonpost.com/local/virginia-news/this-model-of-wealthy-suburban-living-is-starting-to-fray/2016/04/02/e9ad0ace-f107-11e5-a61f-e9c95c06edca_story.html

Volunteer Participation Hits Record Low (2016)
Author: Ali Meyer
The volunteer participation rate in America hit a record low last year, declining 0.4% from the previous year, and has been declining since 2005. Not coincidentally, the racial composition of America has become more fragmented during the same time.
Source: http://freebeacon.com/culture/volunteer-participation-hits-record-low/

How tech created a global village — and put us at each other’s throats (2017)
Author: Nicholas Carr
Globalization and the internet are increasing the proximity of human diversity and consequently increasing mutual animosity as well. “The scholars traced the phenomenon to what they called ‘environmental spoiling.’ The nearer we get to others, the harder it becomes to avoid evidence of their irritating habits. Proximity makes differences stand out.”
Source: https://www.bostonglobe.com/ideas/2017/04/21/how-technology-created-global-village-and-put-each-other-throats/pu7MyoAkdyVComb9aKyu6K/story.html

https://hbr.org/2016/09/diverse-teams-feel-less-comfortable-and-thats-why-they-perform-better
Also, review of performance of companies;
http://www.mckinsey.com/business-functions/organization/our-insights/why-diversity-matters
https://www.gsb.stanford.edu/insights/diversity-work-group-performance - this one agrees with your link, and expands on it



Ethnocentrism
Ethnocentrism is rational, biological, and genetic in origin. Source: http://www.pnas.org/content/108/4/1262.abstract
Babies demonstrate ethnocentrism before exposure to non-Whites. Source: http://onlinelibrary.wiley.com/doi/10.1111/j.1467-7687.2012.01138.x/full
Ethnocentrism is universal and likely evolved in origin. Source: http://www-personal.umich.edu/~axe/research/AxHamm_Ethno.pdf
Races are extended families. Ethnocentrism is genetically rational. Source: http://www.amazon.com/The-Ethnic-Phenomenon-Pierre-Berghe/dp/0275927091
Ethnocentrism is biological in origin and a superior evolutionary strategy to altruism. Source: http://jasss.soc.surrey.ac.uk/16/3/7.html
Humans are more altruistic to individuals who they are more closely related to. Source: http://www.ncbi.nlm.nih.gov/pubmed/17456276
People subconsciously prefer those who are genetically similar to them for biologically rational reasons. Source: http://www.psychology.uwo.ca/faculty/rushtonpdfs/Genetic%20Similarity%201989.pdf
Kinship between members of an ethnic group is greater than expected. Source: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.372.1009

Other listed/discredited:
Health Advantages of Ethnic Density for African American and Mexican American Elderly Individuals
Authors: Kimberly J. Alvarez, MPH, and Becca R. Levy, PhD
Ethnic diversity harms health for Hispanics and Blacks.
Source: http://ajph.aphapublications.org/doi/abs/10.2105/AJPH.2012.300787 or https://www.mailman.columbia.edu/public-health-now/news/living-ethnically-homogenous-area-boosts-health-minority-seniors

Diversity primarily hurts the dominant ethnic group. States with little diversity have more democracy, less corruption, and less inequality.
Source: http://www.theindependentaustralian.com.au/node/57

There is extensive evidence people prefer others who are genetically similar. Dead link.
Source: http://psychology.uwo.ca/faculty/rushtonpdfs/n&n%202005-1.pdf

Ethnic diversity reduces social trust. Source: http://www.nber.org/papers/w5677