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Natural selection shapes diversity across micro and macro-evolutionary scales. Selection causes local adaptation across populations within species and is simultaneously responsible for much of the divergence between species. However, it is unclear if either the force of or the response to selection is the same or different across these scales. Here we show that natural selection drives adaptive divergence between closely related species in a pattern that is distinct from local adaptation within a species. We use reciprocal common-garden transplant experiments across three species ofPhloxwildflowers to show widespread adaptive divergence causing species to have highest fitness in their native habitats. Using provenance trials, we also find that one of thesePhloxspecies has strong local adaptation between populations. We compare the axes of divergence and selection between these two scales of diversity and discover that one suite of traits predicts fitness differences between species and that an independent suite of traits predicts fitness variation within species across individuals. Our work reveals how forces of selection can both drive key divergence between species, allowing for and causing speciation, while simultaneously causing extensive diversity that is maintained across populations within a species. The selection landscape is complex and multidimensional

The recent passing of the renowned anthropologist and anti-racist activist Leith Mullings is a tremendous loss. The three of us became close to Leith through our shared participation in the Antirac...

This article chronicles the long-standing conflict between the Mapuche people and the Chilean state since militarized colonization of Mapuche territory in the 1880s. The analysis focuses especially...

This afterword summarizes the principal contributions of the articles in this collection, noting both common themes and points of difference. All six articles highlight serious problems and uninten...

This essay reviews the following works: Faith and Joy: Memoirs of a Revolutionary Priest. By Fernando Cardenal, S. J. Translated and edited by Kathy McBride and Mark Lester. Maryknoll, NY: Orbis Books, 2015. Pp. xxvi + 288. $28.00 paper. ISBN: 9781626981423. Nicaragua and the Politics of Utopia: Development and Culture in the Modern State. By Daniel Chavez. Nashville: Vanderbilt University Press, 2015. Pp. x + 376. $65.00 cloth. ISBN: 9780826520470. Sandino’s Nation: Ernesto Cardenal and Sergio Ramirez Writing Nicaragua, 1940–2012. By Stephen Henighan. Montreal: McGill-Queen’s University Press, 2014. Pp. v + 776. $33.00 paper. ISBN: 9780773543157. The Awakening Coast: An Anthology of Moravian Writing from Mosquitia and Eastern Nicaragua, 1849–1899. Edited, translated, and annotated by Karl Offen and Terry Rugeley. Lincoln: University of Nebraska Press, 2014. Pp. viii + 448. $75.00 cloth. ISBN: 9780803248960.

Soon after the landslide election of Evo Morales in Bolivia’s 2005 presidential election, the racist backlash began. Political and economic elites and their followers in the eastern media luna (hal...

Enteroaggregative Escherichia coli (EAEC) bacteria are exceptional colonizers that are associated with diarrhea. The genome of EAEC strain 042, a diarrheal pathogen validated in a human challenge study, encodes multiple colonization factors. Notable among them are aggregative adherence fimbriae (AAF/II) and a secreted antiaggregation protein (Aap). Deletion of aap is known to increase adherence, autoaggregation, and biofilm formation, so it was proposed that Aap counteracts AAF/II-mediated interactions. We hypothesized that Aap sterically masks heat-resistant agglutinin 1 (Hra1), an integral outer membrane protein recently identified as an accessory colonization factor. We propose that this masking accounts for reduced in vivo colonization upon hra1 deletion and yet no colonization-associated phenotypes when hra1 is deleted in vitro . Using single and double mutants of hra1 , aap , and the AAF/II structural protein gene aafA , we demonstrated that increased adherence in aap mutants occurs even when AAF/II proteins are genetically or chemically removed. Deletion of hra1 together with aap abolishes the hyperadherence phenotype, demonstrating that Aap indeed masks Hra1. The presence of all three colonization factors, however, is necessary for optimal colonization and for rapidly building stacked-brick patterns on slides and cultured monolayers, the signature EAEC phenotype. Altogether, our data demonstrate that Aap serves to mask nonstructural adhesins such as Hra1 and that optimal colonization by EAEC is mediated through interactions among multiple surface factors. IMPORTANCE Enteroaggregative Escherichia coli (EAEC) bacteria are exceptional colonizers of the human intestine and can cause diarrhea. Compared to other E. coli pathogens, little is known about the genes and pathogenic mechanisms that differentiate EAEC from harmless commensal E. coli . EAEC bacteria attach via multiple proteins and structures, including long appendages produced by assembling molecules of AafA and a short surface protein called Hra1. EAEC also secretes an antiadherence protein (Aap; also known as dispersin) which remains loosely attached to the cell surface. This report shows that dispersin covers Hra1 such that the adhesive properties of EAEC seen in the laboratory are largely produced by AafA structures. When the bacteria colonize worms, dispersin is sloughed off, or otherwise removed, such that Hra1-mediated adherence occurs. All three factors are required for optimal colonization, as well as to produce the signature EAEC stacked-brick adherence pattern. Interplay among multiple colonization factors may be an essential feature of exceptional colonizers.

Enteroaggregative Escherichia coli (EAEC) bacteria are exceptional colonizers of the human intestine and can cause diarrhea. Compared to other E. coli pathogens, little is known about the genes and pathogenic mechanisms that differentiate EAEC from harmless commensal E. coli. EAEC bacteria attach via multiple proteins and structures, including long appendages produced by assembling molecules of AafA and a short surface protein called Hra1. EAEC also secretes an antiadherence protein (Aap; also known as dispersin) which remains loosely attached to the cell surface. This report shows that dispersin covers Hra1 such that the adhesive properties of EAEC seen in the laboratory are largely produced by AafA structures. When the bacteria colonize worms, dispersin is sloughed off, or otherwise removed, such that Hra1-mediated adherence occurs. All three factors are required for optimal colonization, as well as to produce the signature EAEC stacked-brick adherence pattern. Interplay among multiple colonization factors may be an essential feature of exceptional colonizers., Enteroaggregative Escherichia coli (EAEC) bacteria are exceptional colonizers that are associated with diarrhea. The genome of EAEC strain 042, a diarrheal pathogen validated in a human challenge study, encodes multiple colonization factors. Notable among them are aggregative adherence fimbriae (AAF/II) and a secreted antiaggregation protein (Aap). Deletion of aap is known to increase adherence, autoaggregation, and biofilm formation, so it was proposed that Aap counteracts AAF/II-mediated interactions. We hypothesized that Aap sterically masks heat-resistant agglutinin 1 (Hra1), an integral outer membrane protein recently identified as an accessory colonization factor. We propose that this masking accounts for reduced in vivo colonization upon hra1 deletion and yet no colonization-associated phenotypes when hra1 is deleted in vitro. Using single and double mutants of hra1, aap, and the AAF/II structural protein gene aafA, we demonstrated that increased adherence in aap mutants occurs even when AAF/II proteins are genetically or chemically removed. Deletion of hra1 together with aap abolishes the hyperadherence phenotype, demonstrating that Aap indeed masks Hra1. The presence of all three colonization factors, however, is necessary for optimal colonization and for rapidly building stacked-brick patterns on slides and cultured monolayers, the signature EAEC phenotype. Altogether, our data demonstrate that Aap serves to mask nonstructural adhesins such as Hra1 and that optimal colonization by EAEC is mediated through interactions among multiple surface factors. IMPORTANCE Enteroaggregative Escherichia coli (EAEC) bacteria are exceptional colonizers of the human intestine and can cause diarrhea. Compared to other E. coli pathogens, little is known about the genes and pathogenic mechanisms that differentiate EAEC from harmless commensal E. coli. EAEC bacteria attach via multiple proteins and structures, including long appendages produced by assembling molecules of AafA and a short surface protein called Hra1. EAEC also secretes an antiadherence protein (Aap; also known as dispersin) which remains loosely attached to the cell surface. This report shows that dispersin covers Hra1 such that the adhesive properties of EAEC seen in the laboratory are largely produced by AafA structures. When the bacteria colonize worms, dispersin is sloughed off, or otherwise removed, such that Hra1-mediated adherence occurs. All three factors are required for optimal colonization, as well as to produce the signature EAEC stacked-brick adherence pattern. Interplay among multiple colonization factors may be an essential feature of exceptional colonizers.

El mapeo participativo lo han usado comunidades indígenas y afrodescendientes en luchas de derecho a tierras y recursos. Sin embargo, nuevas presiones relacionadas con las políticas de cambio climático y prácticas extractivas han surgido en la reconceptualización del mapeo participativo. Este artículo presenta su historia en el contexto de las reformas territoriales y las leyes internacionales del siglo XX. Se discuten los avances del mapeo participativo, incluyendo usos innovadores de mapeo para representaciones espaciales, conservación cultural y manejo endógeno de recursos y gobernación comunitaria. Estas reflexiones surgen del Foro Internacional Cartografía Participativa y Derechos al Territorio y los Recursos, que tuvo lugar en la Universidad de los Andes (Bogotá, Colombia) en el 2011.

Neoliberalization of the construction industry, in combination with Texas’ anti-labor climate, has resulted in “precarious employment regimes” in Austin’s construction industry. Austin is currently the second fastest-growing urban area in the United States and depends heavily on a Latino immigrant workforce to meet its construction demands. In 2009 a community-based worker center in Austin, Workers Defense Project (WDP), in collaboration with the University of Texas students and faculty, undertook one of the most extensive studies to date on the U.S. construction industry in order to better understand working conditions and to promote fair labor practices and legislation. The study took a participatory activist approach to research and included a survey of 312 construction workers, as well as 37 qualitative interviews with workers and construction industry leaders. Findings revealed an industry characterized by poor and dangerous working conditions, low and stolen wages, limited benefits and racialized divisions of labor, resulting in weakened social citizenship and exclusion. The study exposes the often unaccounted for social, economic and bodily costs of these precarious labor regimes on workers, families, employers and taxpayers. We conclude that the emergent spaces of activism and collective response carved out by immigrant civil society, in particular the worker center movement, are resulting in new forms of social citizenship that are empowering for immigrant workers.

In the early 1990s, an influential group of northern scholars, foundation representatives and observers of academic trends came to the conclusion that ‘Area Studies’ were in crisis. Although the critiques and calls for reformulation applied across the board to a heterogeneous array of Area Studies fields, they had particular resonance within Latin American Studies (LAS). Rooted in disciplinary and institutional developments dating back to the beginning of the 20th century, LAS came into its own in the 1950s, in the context of the Cold War. It rapidly became the largest, most well-funded and most prestigious of the Area Studies fields. For this reason, among others, LAS assumed a central role in the broader debate: should Area Studies persist in their current form? If not, what successor intellectual and institutional configurations should emerge in their place? Nearly twenty years later, this high-stakes debate has virtually disappeared. By various important measures, LAS is thriving. This essay provides ...