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Domesticated maize evolved from wild teosinte under human influences in Mexico beginning around 9000 years before the present (yr B.P.), traversed Central America by ~7500 yr B.P., and spread into South America by ~6500 yr B.P. Landrace and archaeological maize genomes from South America suggest that the ancestral population to South American maize was brought out of the domestication center in Mexico and became isolated from the wild teosinte gene pool before traits of domesticated maize were fixed. Deeply structured lineages then evolved within South America out of this partially domesticated progenitor population. Genomic, linguistic, archaeological, and paleoecological data suggest that the southwestern Amazon was a secondary improvement center for partially domesticated maize. Multiple waves of human-mediated dispersal are responsible for the diversity and biogeography of modern South American maize., (Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Paracoccidioidomycosis is the most common deep mycosis in South America and is caused by Paracoccidioides brasiliensis (P. brasiliensis), a thermally dimorphic fungus. Infections usually occur by inhalation of conidia, which more often cause respiratory, mucocutaneous, and lymph nodal changes. Chronic features of this mycosis can mimic diverse infections and malignancies and constitute diagnosis challenges. Squamous cell carcinoma deserves special attention in this setting. We describe the case of a patient with synchronous diagnosis of oral paracoccidioidomycosis and esophageal squamous cell carcinoma. Concomitance of these conditions may be a casual event, but a not fully understood causal relationship can be involved.