Thirty years after it first began, the Nikon International Small World Competition continues to highlight outstanding photography of the invisible world right in front of our eyes - the world captured by photomicrography. The competition is open to professionals and amateurs alike worldwide, and first prize nets the winner $3,000 toward the Nikon gear of their choosing. Entries are judged on originality, content, technical proficiency and visual impact. The winners of 2015's competition have been announced - take a look above at some of the top images.