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Zaprionus indianus was first reported in South America in 1999 and has rapidly colonised most of the continent since. Previous studies established Brazil as the sole entry point into the continent and the source of its expansion northward, but dispersal to the southern limit of its distribution in South America has not been studied so far. In the present work we extracted DNA of 127 individuals collected in north-eastern Argentina (South America) and amplified the COII mitochondrial gene in order to describe the mitochondrial genetic diversity and shed light about the invasion history of this species into this area. Our results suggest a single Z. indianus introduction wave from Brazil has recently occurred in north-eastern Argentina. In addition, by comparison with available sequences from other locations we can state that the invasive haplotypes present in Argentina are shared with those found in Brazilian populations and are phylogenetically closer to haplotypes from Africa than those found in India. This places Brazil as the sole recipient of the invasion to the American continent and its subsequent dispersion southwards. [ABSTRACT FROM AUTHOR]

Providing somatosensory feedback to amputees is a long-standing objective in prosthesis research. Recently, implantable neural interfaces have yielded promising results in this direction. There is now considerable evidence that the nervous system integrates redundant signals optimally, weighting each signal according to its reliability. One question of interest is whether artificial sensory feedback is combined with other sensory information in a natural manner. In this single-case study, we show that an amputee with a bidirectional prosthesis integrated artificial somatosensory feedback and blurred visual information in a statistically optimal fashion when estimating the size of a hand-held object. The patient controlled the opening and closing of the prosthetic hand through surface electromyography, and received intraneural stimulation proportional to the object's size in the ulnar nerve when closing the robotic hand on the object. The intraneural stimulation elicited a vibration sensation in the phantom hand that substituted the missing haptic feedback. This result indicates that sensory substitution based on intraneural feedback can be integrated with visual feedback and make way for a promising method to investigate multimodal integration processes. [ABSTRACT FROM AUTHOR]