by Lazur URH
When exporting vector images to rasters, there is anti-aliasing which you cannot switch off in inkscape at the moment -featureis planned to be present in 0.93. However, gradients are never rendered with anti-aliasing. This clipart is an example of that "feature": no renderer interprets double gradient steps at the same location with anti-aliasing, therefore such breaks in the gradient produce aliased edges. To be more confusing, openclipart generates thumbnails of 2400 px in width, which means an oversampling when embedded to this page, resulting the aliased edges still look anti-aliased, no matter what.