Although many taxa show a latitudinal gradient in richness, the relationship between latitude and species richness is often asymmetrical between the northern and southern hemispheres. Here we examine the latitudinal pattern of species richness across 1003 local ant assemblages. We find latitudinal asymmetry, with southern hemisphere sites being more diverse than northern hemisphere sites. Most of this asymmetry could be explained statistically by differences in contemporary climate. Local ant species richness was positively associated with temperature, but negatively (although weakly) associated with temperature range and precipitation. After contemporary climate was accounted for, a modest difference in diversity between hemispheres persisted, suggesting that factors other than contemporary climate contributed to the hemispherical asymmetry. The most parsimonious explanation for this remaining asymmetry is that greater climate change since the Eocene in the northern than in the southern hemisphere has led to more extinctions in the northern hemisphere with consequent effects on local ant species richness.

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Wildlife extinction represents the ultimate failure of wildlife conservation. It has many causes, some of them natural, but is increasingly tied to anthropogenic factors. Wildlife loss via domestication, however, is rarely considered. We evaluated the potential for inadvertent domestication of wildlife by determining the effect of feeding and watering on Key deer (Odocoileus virginianus clavium) density, group size, and distribution. Key deer sightings were significantly higher in areas (42 ha) surrounding the households that provided food and water (0.18 deer/m; n= 8) than in randomly selected areas (0.03 deer/m; t = 3.82, 14 df , p = 0.002). Average distance to a household providing food and water decreased logistically as group size increased, and large groups (>2 individuals each) were observed more frequently in areas where food and water were provided (27.5%) than in the randomly selected areas (7.5%). The incidence of large groups outside feeding areas (7.5%), however, was similar to the incidence of large groups during early urbanization (5.1%; 1968-1973). Our results suggest illegal feeding caused changes in density, group size, and distribution indicative of domestication. Because fresh water and food were primary selective pressures for Key deer before illegal feeding and watering, genetic changes may occur in the future. For those who value "wildness" in wildlife, domestication of wildlife species is a serious problem that must be addressed. Pérdida de Vida Silvestre por Domesticación: El Caso de Odocoileus virginianus claviumResumen: La extinción de especies es el fracaso extremo de la conservación de vida silvestre. Tiene muchas causas, algunas naturales, pero cada vez más relacionadas con factores antropogénicos. Sin embargo, raramente se considera la pérdida de vida silvestre por domesticación. Evaluamos el potencial de domesticación accidental de vida silvestre mediante la determinación del efecto del suministro de agua y alimento al venado Odocoileus virginianus clavium sobre su densidad, tamaño del grupo y distribución. Los avistamientos de venados fueron significativamente mayores (0.18 venados/m; n = 8) enáreas (42 ha) circundantes a las casas en las que se les suministró agua y alimento que enáreas seleccionadas al azar (0.03 venados/m; 14 gl, p = 0.002). La distancia promedio a una casa que suministró agua y alimento decreció logísticamente a medida que aumentó el tamaño del grupo, y se observaron grupos grandes (>2 individuos) más frecuentemente eń areas en las que se suministraba agua y alimento (27.5%) que enáreas seleccionadas al azar (7.5%). Sin embargo, la incidencia de grupos grandes afuera deáreas de alimentación (7.5%) fue similar a la incidencia de grupos grandes durante los inicios de la urbanización (6.1%; 1968-1973). Nuestros resultados sugieren que la alimentación ilegal provocó cambios en la densidad, tamaño del grupo y distribución que indican domesticación. En el futuro pueden ocurrir cambios genéticos debido a que el agua fresca y el alimento fueron presiones de selección ...