Stephen P. Yanoviak

Learn More
Animals often depend on properties of reflected light (e.g. color, brightness) to locate resources. We compared reflectance properties of tree trunks with surrounding vegetation, and examined how differences in reflectance profiles of surrogate tree trunks (red, yellow, green, blue, black, gray, dark gray and white sheets) affected the directed aerial(More)
A biomechanically parsimonious hypothesis for the evolution of flapping flight in terrestrial vertebrates suggests progression within an arboreal context from jumping to directed aerial descent, gliding with control via appendicular motions, and ultimately to powered flight. The more than 30 phylogenetically independent lineages of arboreal vertebrate(More)
Numerous non-flying arboreal vertebrates use controlled descent (either parachuting or gliding sensu stricto) to avoid predation or to locate resources, and directional control during a jump or fall is thought to be an important stage in the evolution of flight. Here we show that workers of the neotropical ant Cephalotes atratus L. (Hymenoptera: Formicidae)(More)
In contrast to the patagial membranes of gliding vertebrates, the aerodynamic surfaces used by falling wingless ants to direct their aerial descent are unknown. We conducted ablation experiments to assess the relative contributions of the hindlegs, midlegs and gaster to gliding success in workers of the Neotropical arboreal ant Cephalotes atratus(More)
Since Venezuelan equine encephalitis virus (VEEV) was isolated in Peru in 1942, >70 isolates have been obtained from mosquitoes, humans, and sylvatic mammals primarily in the Amazon region. To investigate genetic relationships among the Peru VEEV isolates and between the Peru isolates and other VEEV strains, a fragment of the PE2 gene was amplified and(More)
BACKGROUND Anopheles darlingi is the most important malaria vector in the Neotropics. An understanding of A. darlingi's population structure and contemporary gene flow patterns is necessary if vector populations are to be successfully controlled. We assessed population genetic structure and levels of differentiation based on 1,376 samples from 31 localities(More)
Directed aerial descent (DAD) is used by a variety of arboreal animals to escape predators, to remain in the canopy, and to access resources. Here, we build upon the discovery of DAD in ants of tropical canopies by summarizing its known phylogenetic distribution among ant genera, and within both the subfamily Pseudomyrmecinae and the genus Cephalotes. DAD(More)
Tropical forest canopies house most of the globe's diversity, yet little is known about global patterns and drivers of canopy diversity. Here, we present models of ant species density, using climate, abundance and habitat (i.e. canopy versus litter) as predictors. Ant species density is positively associated with temperature and precipitation, and(More)
Gliding ants avoid predatory attacks and potentially mortal consequences of dislodgement from rainforest canopy substrates by directing their aerial descent towards nearby tree trunks. The ecologically relevant measure of performance for gliding ants is the ratio of net horizontal to vertical distance traveled over the course of a gliding trajectory, or(More)
Upon falling onto the water surface, most terrestrial arthropods helplessly struggle and are quickly eaten by aquatic predators. Exceptions to this outcome mostly occur among riparian taxa that escape by walking or swimming at the water surface. Here we document sustained, directional, neustonic locomotion (i.e. surface swimming) in tropical arboreal ants.(More)